Category: Blog

A dry summer is over, the rain has returned, and you’ve noticed cracks in your walls that weren’t there in spring. You’re hoping they’ll quietly close up on their own — but if your house sits on clay soil, that hope is probably misplaced, and acting on it too quickly could cost you significantly more than waiting and watching.

Key Takeaways

• Cracks appearing after a dry summer on clay ground are often caused by soil shrinkage beneath shallow foundations — a well-understood mechanism, not a structural emergency.
• Autumn rain does not quickly reverse months of clay shrinkage; rehydration is slow, sometimes taking more than one winter to complete.
• The most useful diagnostic is whether cracking is cyclical — partially closing in winter and reopening the following summer — or steadily progressive. That distinction matters more than the crack width on any single day.
• Do not fill and redecorate immediately: you destroy the baseline evidence an engineer needs to assess what the crack is actually doing.
• Do not fell a nearby tree, and do not notify your insurer, until you have an engineering view on what the cracking represents.

Two Misconceptions Pulling in Opposite Directions

The first misconception is that a crack appearing in August means the house is falling down. The second is that the first heavy autumn downpour will put it right. Both are wrong, and the second is the more expensive mistake. It persuades homeowners to fill cracks and redecorate before anyone has understood what those cracks are doing — which destroys the very evidence that would have guided a sensible decision.

If you’ve found this article, you’re probably somewhere between those two positions: worried enough to search online, but hoping for a calm, specific explanation rather than a scare story. That’s what I’ll try to give you. This post is written from general engineering principles about how clay soils and shallow foundations behave — not from a single case study — because the mechanism is consistent enough that the principles apply broadly.

What Is Actually Happening Under Your House

Shrinkable clay soils change volume with their moisture content. Through a dry summer, a soil moisture deficit builds up gradually. The clay shrinks, and the ground beneath a shallow foundation can move downward — unevenly, because soil conditions are never perfectly uniform. That process is subsidence, and it’s worth being precise about the word, because it gets used loosely. Subsidence is ground movement causing a structure to move with it. It is distinct from settlement, which is the initial bedding-down of a new building under its own weight, and from heave, which is the ground swelling upward as clay rehydrates.

Vegetation is the accelerant. A mature tree in leaf transpires a considerable volume of water, drawing moisture from a zone that extends well beyond the canopy edge. The species, the mature height, and the distance from the building all matter. NHBC Standards Chapter 4.2 on building near trees is the reference practitioners use: it relates foundation depth to tree proximity, the water demand of different species, and the volume change potential of the clay. It is the reason that foundations near trees on clay are designed to go deeper than they otherwise would.

Foundation depth is ultimately what decides the outcome. Seasonal moisture change is concentrated in the upper metre or so of the ground. A foundation founded below that active zone is largely indifferent to a dry summer. A shallow strip footing — common in older housing stock — is not. This is why two neighbouring houses on the same clay can behave completely differently in a hot, dry year.

Why the Rain Does Not Fix It

The intuition that autumn rain will reverse the summer’s damage is understandable but incorrect, and understanding why matters if you’re deciding what to do next.

Clay that has dried out over several months does not recover in a weekend. Rehydration is slow. Intense rainfall — the kind that arrives after a prolonged dry spell — tends to run off a hard, desiccated surface rather than infiltrate it. The moisture that does penetrate works its way down gradually. Recovery is measured in months, and in a significant shrinkage event it can extend across more than one winter season.

What this means practically is that cracks which opened in July or August may still be open — or only marginally narrower — by November. That is not evidence that something catastrophic is happening. It is evidence that the clay hasn’t recovered yet. The question is whether the cracking is cyclical or progressive, and you cannot answer that from a single observation.

The Cyclical Signature — the Most Useful Thing to Watch For

Because the mechanism is seasonal, clay shrinkage cracking often partially closes over winter and reopens the following summer. That cyclical behaviour is genuinely informative in a way that a single crack width is not. It is the signature of a building responding to seasonal ground movement — uncomfortable, potentially costly if ignored over many years, but a different category of problem from progressive structural failure.

Progressive damage — cracking that widens steadily, never recovers between seasons, and is accompanied by doors and windows that increasingly bind or floors that go noticeably out of level — is telling a different story. That warrants more urgency and earlier professional input.

This is why crack monitoring across at least one full seasonal cycle is so valuable. A single reading tells you a crack exists. A series of readings, taken at intervals with a proper gauge and recorded with dates and widths, tells you whether the crack is seasonal, static, or progressive. That is the question on which everything else depends.

What a Structural Engineer Is Actually Reading

When I attend a property to assess cracking, I’m not just looking at the width. Several things together build a picture.

Direction and pattern. Diagonal and stepped cracking through masonry, often running from the corners of openings — windows and doors — is characteristic of differential settlement or subsidence. Openings are the weak points in a wall, and that’s where the stress concentrates.

Taper. Whether a crack is wider at the top or the bottom says something about whether the movement is rotational or predominantly vertical. A crack that is wide at the top and closes toward the base suggests the wall is tilting; one that is wide at the base suggests something different.

Distribution. Whether cracking appears internally, externally, or both, and whether it is consistent with a single point of movement or scattered, all contribute to the interpretation.

Corroborating evidence. Doors and windows that bind, floors that have gone out of level, and gaps opening at skirtings or cornices are all part of the picture. They help confirm that what looks like cracking in the masonry corresponds to real movement in the structure.

BRE Digest 251, “Assessment of damage in low-rise buildings”, provides the damage classification framework that engineers use to categorise severity — separating aesthetic damage from damage that affects serviceability or stability. Categorising damage properly requires measurement and context. A photograph sent to an online forum cannot do it.

Three Things Not to Do

These three actions are common, understandable, and often make the situation worse.

• Do not fill and redecorate immediately. Fresh filler destroys the baseline. If a crack later reopens through new filler, you’ve lost the ability to say when it started, how wide it was originally, and whether it has changed. That information is exactly what an engineer needs, and once it’s gone, it’s gone.
• Do not fell a mature tree close to the house without advice. This is counterintuitive, but important. A tree that has been drawing moisture from the clay for decades has established an equilibrium. Remove it suddenly, and the clay begins to rehydrate. Heave — the ground swelling upward — can follow, and heave damage is often more severe and harder to remedy than the shrinkage it replaced. Any decision about removing a tree near a house on clay should involve an engineering view first.
• Do not notify your insurer as a reflex. A subsidence notification attaches to the property history. It has consequences for future insurability, for premium levels, and for a sale — some buyers’ solicitors will flag it and some lenders will require additional surveys. It is worth having an independent engineering view on what the cracking actually represents before you make that call. If it turns out to be superficial seasonal movement rather than active subsidence, you may have notified unnecessarily.

When to Call a Structural Engineer

If cracking appeared this summer, is wider than a couple of millimetres, runs diagonally from the corners of openings, or is accompanied by binding doors, sloping floors, or gaps opening at junctions, get it looked at by a chartered structural engineer before you do anything else. The same applies if there is a mature tree within striking distance of the house and you’re on clay. You don’t necessarily need a full investigation immediately — sometimes a site visit and a monitoring programme is the right first step — but you do need someone who can tell you which category of problem you’re dealing with. Acting without that understanding, in either direction, is where the expensive mistakes happen.

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Need expert eyes on your project?

I am a Chartered Structural Engineer (CEng, MIStructE) based in Huddersfield. The Beam Doctor offers homeowners and builders:

• Steel beam (RSJ) calculations — Eurocode-compliant, Building Control-ready, in 5 working days. See all services and current fees →
• Defect investigation — I attend your property, inspect the cracking or movement, and give you a written opinion on the cause. The site visit is included in the price. See the fee bands →
• Structural Engineer’s Report — a signed desk-based opinion on a single structural concern, for a mortgage lender or an insurance claim. Request a report →
• On-site attendance — a Chartered Engineer at your property, tiered by duration. See site visit fees →

You’ve found a builder you trust, you’ve picked out your open-plan kitchen, and then the structural engineer turns up and says the temporary works need a complete rethink. If your home is a pre-1900 stone-built terrace or semi in West Yorkshire — and you’re planning to knock through an internal wall — what follows is exactly why that conversation matters, and why the method your builder prices for a brick wall simply isn’t safe for solid stone.

Key Takeaways

• Victorian internal stone walls are not homogenous masonry — they have a loose rubble-filled core that behaves unpredictably once disturbed.
• Standard single-row propping and needling, perfectly adequate for modern brick, can lose bearing in a stone wall before the permanent beam is even in place.
• Temporary works for this wall type need an engineer-specified scheme under BS 5975, with closer needle spacing and sequential cutting — not all pockets opened at once.
• Shallow historic footings and shared loads from chimney breasts, joists, and roof structure make the risk profile fundamentally different from a cavity wall.
• If the wall adjoins a neighbour, a Party Wall Act notice is required before any work begins — this is a legal obligation, not a courtesy.

What’s actually inside a Victorian stone wall

Most homeowners assume a thick stone wall is just that — solid stone, all the way through. On a recent site visit to a pre-1900 stone-built semi in the Shepley area near Huddersfield, I had to explain to both the owner and the builder why that assumption is wrong, and why it changes everything about how you approach a knockthrough.

West Yorkshire stone walls of this era are typically built as two skins of dressed facing stone — the courses you can see on the outside and inside face — with a loose rubble-filled core in between, known as hearting. The whole assembly is held together by occasional through-stones that span the full thickness, but there are far fewer of these than you might hope. The mortar is usually a weak lime mix, which has often degraded over 120-plus years.

What this means in practice is that the wall behaves like a sandwich where the filling is not bonded to the bread. The moment you start cutting needle pockets, you disturb the equilibrium that has kept everything in place for a century. That loose hearting can shed — suddenly and unpredictably — into the opening. When it does, the needle loses its bearing surface. If a prop is carrying significant load at that moment, the consequences can be serious.

A modern brick cavity wall, by contrast, is two skins of fired clay units laid in a consistent bond pattern with a predictable, relatively uniform compressive strength. The temporary works calculations for brick rely on that uniformity. Stone hearting offers no such guarantee.

Why the builder’s standard propping method isn’t enough

On the Shepley job, the builder had priced temporary works on a single-row propping and needling arrangement — the same approach they’d use on a standard brick wall. That’s not a criticism of the builder; it’s a very common assumption, and for brick it’s often perfectly appropriate. But for this wall type it isn’t safe, and here’s the engineering reason.

In a brick wall knockthrough, you cut your needle pockets, insert the needles, prop underneath, and then remove the masonry in the opening. The wall above redistributes load into the needles in a reasonably predictable way. The spacing between needles — often 1.2 m to 1.5 m on a brick wall — reflects that predictability.

For a stone wall with a rubble core, the engineer-specified scheme needs to be more conservative. On this job I specified maximum needle spacings of 900 mm to 1.2 m, with needle pockets cut sequentially rather than all at once. Opening multiple pockets simultaneously removes too much of the restraint that’s holding the hearting in place. You cut one, insert and prop, then move to the next. It takes longer. It costs more in labour. But it’s the only way to maintain control of what’s above you.

The props also need spreader plates beneath them — not just resting on the floor boards. Victorian ground floors often sit on shallow footings, typically 450 mm to 600 mm deep with no engineered ground preparation beneath. A concentrated prop load on a small bearing area can punch through or cause differential settlement. Spreader plates distribute that load across a larger area and protect the foundation.

The beam arrangement is different too

When removing an internal stone wall in a Victorian property, a simple needled lintel — the kind of arrangement that works well in a modern build — is often not the right answer. The wall thickness, the load paths above, and the limited bearing surface of the stone all point toward a picture-frame or goalpost steel arrangement instead.

A goalpost frame uses two vertical steel members (the posts) bearing down to the floor, with the horizontal beam spanning between them at the top. This transfers the load from above down to the floor structure and foundations in a controlled way, rather than relying entirely on end bearings in the remaining masonry. It also means the beam can be installed and the frame made stable before the masonry in the opening is fully removed.

End bearings on stone walls need particular attention. I specify a minimum of 150 mm bearing length, and critically, the beam must bear onto a solid full stone — not onto a joint, not onto a half-stone, and not onto hearting. Finding that solid bearing point sometimes means adjusting the beam position slightly once the wall is opened up. That’s a decision that needs an engineer present or at least a very clear specification in advance, not a judgement call left to the bricklayer on the day.

Load paths you might not have thought about

Victorian terraces and semis were built when internal walls did a lot of structural work. The wall you want to remove may be carrying far more than just the floor above. On the Shepley property, I identified three separate load sources feeding into the wall: a chimney breast on the floor above, first-floor joists bearing onto the wall’s full thickness, and roof load transferred down through the party wall and internal walls in combination.

This is why removing an internal stone wall in a Victorian property is not simply a matter of calculating the span and sizing a beam. You need to trace the load path from the roof down to the foundations and understand what the wall is doing at every level. Sometimes a wall that looks like a simple partition is actually a key element in the building’s overall stability — particularly where it acts as a lateral restraint to a party wall or provides support to a chimney stack.

The party wall itself is another consideration. If the stone wall you’re opening up runs close to or connects with the wall shared with your neighbour, you almost certainly need to serve a Party Wall Act notice on the adjoining owner before work begins. This is a legal requirement under the Party Wall etc. Act 1996, not optional. Your neighbour has the right to appoint a surveyor, and the process needs to be started well in advance of your planned start date — typically at least two months.

The red flag to watch for

The homeowner angle here is straightforward: if your builder looks at a thick Victorian stone wall and says “we’ll just prop it and cut through” — using the same method and the same temporary works they’d use on a brick wall — that’s a red flag. It doesn’t mean the builder is incompetent. It means they may not have encountered this wall type before, or they may be pricing to win the job rather than pricing the actual risk.

The temporary works on a stone wall knockthrough are genuinely more involved than on brick. They take longer, they require sequential working, and they need to be specified by an engineer rather than left to site judgement. That specification should reference BS 5975, the code of practice for temporary works procedures, and it should be in writing before a single needle pocket is cut.

I’ve seen what happens when this step is skipped or rushed. The cost of putting it right — shoring a partially collapsed opening, re-supporting a chimney breast that has moved, dealing with a cracked party wall — is always far greater than the cost of getting the temporary works right in the first place.

When to call a structural engineer

If you’re planning to remove any internal wall in a pre-1900 stone-built property, call a structural engineer before you appoint a builder — not after. You need the temporary works scheme, the beam specification, the bearing details, and the Party Wall Act position all established before anyone prices the job. If the wall is thick, if it carries a chimney, if it’s close to the party wall, or if your builder hasn’t specifically mentioned a sequential needling approach, those are all reasons to get an independent engineer’s assessment. The structural integrity of your home during the works is just as important as the finished result.

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Need expert eyes on your project?

I am a Chartered Structural Engineer (CEng, MIStructE) based in Huddersfield. The Beam Doctor offers homeowners and builders:

• Steel beam (RSJ) calculations — Eurocode-compliant, Building Control-ready, in 5 working days. See all services and current fees →
• Defect investigation — I attend your property, inspect the cracking or movement, and give you a written opinion on the cause. The site visit is included in the price. See the fee bands →
• Structural Engineer’s Report — a signed desk-based opinion on a single structural concern, for a mortgage lender or an insurance claim. Request a report →
• On-site attendance — a Chartered Engineer at your property, tiered by duration. See site visit fees →

You’ve sketched the footprint, had a rough quote from your builder, and the project feels real. Then someone mentions a drain — and suddenly the budget you were confident about has a hole in it. Underground drainage is the single most common thing an extension design gets wrong, and the reason is straightforward: you can’t see it.

Key Takeaways

• Never fix an extension footprint or finalise a budget before you’ve located all drainage — including public sewers that may cross your plot.
• Building over or within roughly 3 m of a public sewer requires a formal build-over or build-near agreement with the sewerage undertaker — a process entirely separate from Building Control approval, with its own fees and timeline.
• Water authority records are useful but not reliable enough on their own; confirm sewer positions physically with a CCTV drainage survey and trial holes before you design.
• Where a sewer is unavoidably close, foundations must be detailed to keep the pipe outside the structural zone of influence — or to bridge over it so no load is imposed on the pipe at all.
• The earlier you engage Building Control and the sewerage undertaker, the cheaper the problem is to solve. A sewer found on site redesigns the foundations and rewrites the budget.

The assumption that costs homeowners money

I was called in on a suburban extension — a fairly standard single-storey rear addition — where a public sewer sat under, or within a few metres of, the proposed footprint. Nobody had checked. The initial design had been drawn up, a builder was lined up, and the client had a budget in mind. When the sewer came to light, Building Control required a formal build-over agreement with the sewerage undertaker before they’d sign off the foundation design. That agreement meant a separate application, a fee, a survey, and a wait. The project didn’t stop, but it slowed down and cost more than anyone had planned for.

This is not unusual. It happens regularly on extension projects because underground drainage is invisible and the record information held by water authorities is frequently incomplete or positionally inaccurate. The records are described, quite honestly, as “believed to be correct” — which is not the same as correct. An extension designed around incomplete information is an extension designed around an assumption, and assumptions underground tend to surface at the worst possible moment.

The lesson from that job is simple: drainage is a design-stage question, not a construction-stage discovery. If you treat it that way, it’s a manageable constraint. If you don’t, it becomes an emergency.

Locating drainage before you design

The first step is to obtain the sewerage undertaker’s public sewer records and asset plans for your area. In England, this means contacting the relevant water company — Thames Water, Yorkshire Water, United Utilities, and so on depending on your region — and requesting a sewer map. You should also commission a utility search, which covers gas, electricity, telecoms and water mains as well as drainage. These searches are not expensive and they are essential.

What they are not is definitive. Sewer records can be out of date, mis-plotted, or simply absent for older infrastructure. A Victorian-era combined sewer may not appear on any digital record at all. This is why the physical verification step matters just as much as the desk research.

A CCTV drainage survey — where a camera is pushed through the drain from an access point — will confirm the pipe’s condition, diameter, depth, and precise line. Where records are vague or absent, trial holes (carefully excavated pits to expose the pipe) give you the invert level and the exact position. Approved Document H of the Building Regulations and BS EN 752 govern surface water and foul drainage design, and both assume you know where your drainage is before you start detailing around it. That knowledge has to come from physical investigation, not from a map alone.

Do this work before the architect finalises the footprint. It costs a fraction of a foundation redesign.

The build-over agreement: what it is and why it matters

Once you know a public sewer is under or near your proposed extension, you need to understand what “near” means in regulatory terms. As a general rule, building over a public sewer, or constructing within approximately 3 m of one, requires a build-over or build-near agreement with the sewerage undertaker. The exact threshold can vary — the water company will confirm their requirements — but 3 m is the figure most commonly applied in practice.

Approved Document H4 sets out the principles governing building over or near drains and sewers. It is worth reading, but the agreement itself is not a Building Control process. It is a separate application made directly to the water company, with its own form, its own fee, its own technical requirements, and its own timeline. Building Control will not approve your foundation design without evidence that the build-over agreement is in place or in progress. The two processes run in parallel, and both take time.

The water company will typically require a CCTV survey of the sewer before and after construction, evidence that the foundation design does not impose load on the pipe, and details of how access to the sewer is maintained for future maintenance. Some sewers cannot be built over at all — particularly larger-diameter or structurally compromised pipes — in which case the extension footprint may need to change.

None of this is insurmountable. But it cannot be resolved in a week, and it cannot be resolved after the foundations are poured. Identify it at feasibility, engage the water company early, and build the agreement process into your programme and your budget.

Foundation detailing near a sewer

When a sewer is unavoidably close to a proposed foundation, the structural challenge is straightforward to state and requires careful detailing to solve. A strip or pad foundation spreads its load into the ground at roughly 45° from the base of the foundation. Any pipe that falls within that cone of influence is at risk of being overloaded, cracked, or displaced as the ground settles under the new load.

There are three principal remedies, and which one applies depends on the geometry:

• Keep the foundation clear of the pipe. If the sewer is close but not directly beneath the footprint, repositioning the foundation so the 45° zone does not intersect the pipe is the simplest solution — provided the footprint can accommodate it.
• Deepen the foundation below the pipe invert. If the foundation is taken down below the level of the pipe, the zone of influence passes beneath it rather than through it. This requires accurate knowledge of the invert depth, which is another reason the CCTV survey and trial holes matter.
• Bridge over the drain. Where neither of the above is practical, a reinforced concrete lintel or beam can be designed to span over the pipe, transferring the load to bearing points on either side and imposing no load on the drain itself. This is the most engineered solution and requires proper structural design.

In all cases where a pipe passes through or close to the structure, Approved Document H calls for rocker pipes — short pipe sections with flexible joints — at approximately 150 mm and 750 mm from the face of construction. These accommodate the small differential movements that inevitably occur between a new foundation and the surrounding ground, without cracking the drain. A granular or concrete surround to the pipe provides additional protection against point loads and disturbance during construction.

These details are not complicated, but they must be designed by someone who understands the load paths. Getting them wrong damages a pipe you cannot see and may not notice until it causes a problem years later.

Coordination: the thing that actually makes it work

The thread running through all of this is coordination, and it has to happen early. Three separate parties have an interest in how your extension sits relative to a public sewer: Building Control, who approve the structural and drainage design; the sewerage undertaker, who own the pipe and issue the build-over agreement; and in some cases the local authority, particularly where highway drainage or adopted infrastructure is involved.

These parties do not automatically talk to each other. It is the designer’s job — and ultimately the homeowner’s responsibility to insist on — making sure all three are engaged before the footprint is fixed and the budget is committed. A pre-application conversation with Building Control costs nothing and can identify the drainage question before it becomes a problem. A call to the water company’s build-over team at the same stage tells you whether an agreement is required and how long it is likely to take.

The homeowners who get caught out are the ones who treat drainage as someone else’s problem until it becomes everyone’s problem. The ones who don’t get caught out are the ones who ask the question before they start digging.

When to call a structural engineer

You need a structural engineer involved as soon as drainage investigation reveals a public sewer within or near your proposed extension footprint. The foundation design around that sewer — whether you’re deepening, repositioning, or bridging — requires structural calculations that Building Control will expect to see, and that the sewerage undertaker’s build-over application will often require as supporting documentation. If you’re at the stage of commissioning a CCTV survey or trial holes and the results show a pipe closer than you’d hoped, that’s the moment to pick up the phone. Trying to resolve the structural detailing without professional input at that point is how small problems become expensive ones.

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Need expert eyes on your project?

I am Paul, a Chartered Structural Engineer (CEng, MIStructE) based in Huddersfield. The Beam Doctor offers homeowners and builders:

• Steel beam (RSJ) calculations — Eurocode-compliant, Building Control-ready, in 5 working days. See all services and current fees →
• Defect investigation — I attend your property, inspect the cracking or movement, and give you a written opinion on the cause. The site visit is included in the price. See the fee bands →
• Structural Engineer’s Report — a signed desk-based opinion on a single structural concern, for a mortgage lender or an insurance claim. Request a report →
• On-site attendance — a Chartered Engineer at your property, tiered by duration. See site visit fees →

You’ve planned every detail of your new garage or workshop — the floor, the electrics, the big roller-shutter door — but there’s one calculation that often gets skipped entirely: what happens to the roof when that door is open and the wind drives straight in. It’s a question I get asked less often than I should, and the answer surprises most people.

Key Takeaways

• A large open door pressurises the inside of a building, pushing the roof upward from below — this is the “dominant opening” case, and it must be checked explicitly in any wind assessment.
• Garage roof wind uplift with the door open can far exceed the uplift on the same building with the door shut — it often governs the design of the roof fixings, the purlins, and the column bases.
• Light steel-framed, metal-clad buildings have very little self-weight to resist uplift, which makes holding-down at the foundations critical.
• The door’s position relative to the prevailing wind genuinely changes the numbers — a door on the windward face is the worst case.
• Before you build a large detached garage, workshop, or car barn with a big door, make sure the wind loading has been designed for the door-open condition. Don’t let it be built like an oversized shed.

Why “it’s only a garage” is the wrong way to think about it

I’ve lost count of the number of times a client has prefaced a question with “I know it’s only a garage, but…” — as though the word garage somehow reduces the forces nature applies to a structure. It doesn’t. A large detached garage or workshop, particularly one with a big roller-shutter or up-and-over door, can be subjected to wind loads that would concern any structural engineer, and the door itself is the reason why.

The job that crystallised this for me was a steel-framed, metal-clad workshop unit — roughly 13 metres by 6.6 metres on plan, with eaves at around 4.8 metres — on a flood-risk plot in the East of England. It had a large roller-shutter door on one face. The brief required a full wind assessment, and when I ran the door-open case alongside the standard closed-building case, the open-door condition governed almost everything: the roof sheet fixings, the purlin and rafter connections, and above all the holding-down at the column bases. The foundation — a raft — had to be sized not just to spread the building’s modest weight across soft, flood-affected ground, but to act as a dead-weight anchor against the roof trying to lift off. That’s a different design problem entirely from “build a slab and sit a frame on it.”

What actually happens when you open the door

Wind design isn’t only about pressure pushing on the outside of a building. The pressure inside matters just as much, and a large opening is what changes it dramatically.

When a building is closed up — windows shut, personnel doors shut — the internal pressure is modest. The Eurocode for wind actions, EN 1991-1-4, gives relatively small internal pressure coefficients for a closed building: roughly +0.2 on the positive side and −0.3 on the negative side. Those values are manageable, and for a typical closed building the roof uplift is real but not usually the thing that keeps an engineer awake.

Now open a large roller-shutter door on the windward face. Under the Eurocode’s treatment of dominant openings — an opening whose area is at least twice the combined area of openings on the other faces — the internal pressure coefficient jumps sharply. When the large door is roughly twice the area of all other openings combined, the internal pressure coefficient climbs to around 0.75 times the external pressure coefficient at that opening. When it’s three times or more, it reaches around 0.90. That internal over-pressure pushes outward on all surfaces simultaneously: outward on the walls, and — critically — upward on the underside of the roof.

At the same time, the wind is creating suction on the leeward roof slope in the normal way. Those two effects — internal over-pressure pushing up, external suction pulling up — stack on top of each other. The net uplift on the roof with the door open can be dramatically greater than with it shut. For a light structure with little self-weight, that combined uplift becomes the governing load case.

Why light steel and metal cladding make this worse

A heavy masonry building has one significant advantage in a storm: it’s heavy. Dead weight resists uplift. A steel-framed, metal-clad building — the kind typically used for garages, workshops, car barns, and agricultural stores — is deliberately light. That’s part of its appeal: fast to erect, economical, no need for a heavyweight foundation. But lightness is a liability when the wind is trying to lift the roof.

With very little self-weight to call on, the structural engineer has to design positive anchorage at every level. The roof sheets must be fixed for suction and uplift, not just for someone walking across them during installation. The purlins and rafters must be connected to resist being pulled away from the frame, not just sitting on it. And the column bases must be bolted down to the foundation with holding-down bolts sized to resist a net upward pull — not simply transferring a downward load into the ground as you might assume.

That last point is the one that surprises builders most. People instinctively think of a column base as something that carries load downward. In the door-open, windward-face case, the column on the windward side can be in net tension — pulling upward on the foundation. If the holding-down bolts and the foundation itself haven’t been designed for that, the building can fail at the base rather than at the roof.

The position of the door relative to the wind matters

Not every large door creates the same risk. The dominant-opening effect is worst when the door faces into the prevailing wind — when the wind drives straight through the opening and pressurises the interior most efficiently. A door on a sheltered leeward face, or on a face perpendicular to the prevailing wind, produces a different internal pressure condition and a less severe uplift result.

In the East of England job, the roller-shutter sat on a face that the wind could drive directly into. That made it the worst-case geometry. In practice, you won’t always be able to choose your door position — the site, the access, and the layout of the building will often dictate it — but it’s worth understanding that the choice has structural consequences. If you’re at the planning stage and have flexibility over which face the large door goes on, that conversation is worth having with your structural engineer before the design is fixed.

Equally, the size of the door relative to the other openings matters. A modest personnel door on the opposite face, a couple of small windows, and a large roller-shutter on the windward face is a classic dominant-opening geometry. If you add more openings on the other faces — or reduce the size of the main door — the dominant-opening condition may not apply, and the internal pressure remains more benign. Again, this is a calculation, not a rule of thumb.

What a proper wind assessment covers for a big-door building

Part A (Structure) of the Building Regulations, supported by Approved Document A, requires that a building is designed to resist all the loads it will realistically experience — and wind is explicitly among them. For any building with a large opening, a proper wind assessment following EN 1991-1-4 must include the dominant-opening case. It is standard chartered practice, not an optional extra.

In practical terms, that assessment needs to address several things:

• The door-open case explicitly. The closed-building wind loads are not sufficient on their own. The dominant-opening calculation must be run, and whichever case governs must be used for design.
• Roof sheet fixings for uplift. The fixing specification — screw type, spacing, pull-out capacity — must be checked against the uplift load, not just the gravity load.
• Purlin and rafter connections. These must be designed to resist being pulled away from the primary frame under suction.
• Column base holding-down. Bolt sizes, embedment, and the foundation itself must be checked for net upward load on the tension columns.
• Foundation dead weight. For a light building, the foundation may need to be heavier than a simple gravity design would suggest — purely to provide the anchorage mass the building needs to stay on the ground.

In the East of England job, the raft foundation earned its keep twice: once as a way of spreading the building’s modest weight across soft, flood-affected ground, and again as the dead-weight anchor that stopped the roof from lifting. That dual role had to be recognised and designed for from the outset.

A practical note for self-builders and their builders

If you’re pricing up a large detached garage, workshop, or car barn, the quote you receive from a steel-frame supplier will almost certainly be based on a closed-building wind assessment — or possibly on no wind assessment at all beyond a generic wind speed lookup. That’s not necessarily negligence; it’s often just the way the market works for smaller structures. But it means the holding-down details, the roof sheet fixing specification, and the column base design may not have been checked for the door-open condition.

Ask the question directly: has the dominant-opening case been checked? If the answer is uncertain, or if the building has a large door on a windward face and is steel-framed with metal cladding, commission an independent wind assessment before the frame goes up. It is considerably easier — and cheaper — to upsize a holding-down bolt or add fixings to a roof sheet specification at design stage than to retrofit anchorage after a storm has demonstrated the problem.

And whatever the design says: shut the door in a storm. The dominant-opening condition requires the door to be open. Keeping it shut removes the worst-case internal pressure entirely. That’s not a substitute for correct design, but it is a sensible operational precaution that costs nothing.

When to call a structural engineer

If you’re planning any large detached garage, workshop, outbuilding, or car barn with a roller-shutter, up-and-over, or other large door — particularly a steel-framed, metal-clad structure — you should involve a structural engineer before the design is finalised. The same applies if you’re buying an existing building of this type and want to understand whether it was designed correctly. If a supplier or builder cannot confirm that the door-open dominant-opening case has been checked under EN 1991-1-4, and that the roof fixings, rafter connections, and column base holding-down have been designed accordingly, that is the point to seek independent engineering input. A wind assessment and holding-down design for a building of this size is not a large piece of work — but skipping it can have serious consequences when the first significant storm arrives.

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Need expert eyes on your project?

I am a Chartered Structural Engineer (CEng, MIStructE) based in Huddersfield. The Beam Doctor offers homeowners and builders:

• Steel beam (RSJ) calculations — Eurocode-compliant, Building Control-ready, in 5 working days. See all services and current fees →
• Defect investigation — I attend your property, inspect the cracking or movement, and give you a written opinion on the cause. The site visit is included in the price. See the fee bands →
• Structural Engineer’s Report — a signed desk-based opinion on a single structural concern, for a mortgage lender or an insurance claim. Request a report →
• On-site attendance — a Chartered Engineer at your property, tiered by duration. See site visit fees →

Current fees for every service are listed on the services page.

You’re planning to open up two rooms into one, and someone — your builder, a neighbour, maybe a quick Google search — has already mentioned a steel beam. Before you budget for structural steelwork, it’s worth knowing that the answer to “do I need a steel beam removing a wall?” sometimes turns out to be no — and a twenty-minute look in the loft is often what proves it.

Key Takeaways

• Whether an internal wall needs a steel beam depends almost entirely on whether it carries load — and that’s determined by your roof type, not by the wall itself.
• Factory-made trussed rafters (the W-shaped frames common in 1970s volume-build homes) transfer all roof load to the external walls, leaving internal partitions carrying nothing structural.
• A traditional “cut” roof with purlins and struts is a different matter entirely — there, an internal wall often is genuinely load-bearing and removing it without a beam causes real damage.
• Four things visible in the loft settle the question before anyone picks up a sledgehammer — and a chartered engineer can read them in a single inspection.
• Even a non-load-bearing wall removal is a material alteration under the Building Regulations 2010, so Building Control and fire separation rules still apply.

The job that reversed a two-beam design

A homeowner in West Yorkshire had recently bought a 1970s detached bungalow and wanted to knock through two internal partitions to create an open-plan kitchen, dining, and living space. The initial scope — from a builder who’d done plenty of these — assumed two steel beams, padstones, and the associated Building Control beam calculations. It’s a reasonable default. Most people asking “do I need a steel beam removing a wall?” are told yes before anyone has looked at the structure properly.

I went to site, spent about twenty minutes in the loft, and the whole picture changed. Both walls were non-load-bearing. No steel, no padstones, no temporary propping sequence beyond basic safety. The walls simply came out. The job that had been scoped as a structural steelwork package turned into a straightforward partition removal — because the roof told the whole story.

Why the roof type is the governing fact

The load path in a house starts at the roof and works downward. If the roof structure deposits its weight onto internal walls, those walls are load-bearing and removing them without a beam will cause the structure above to move — roof spread, sagging ceiling, cracking. If the roof structure bypasses the internal walls entirely and delivers its load straight to the external walls, the internal partitions are just room dividers. Understanding which situation you’re in is the whole question.

This bungalow had factory-made W-profile trussed rafters — the Fink truss, the standard for volume-build homes from the late 1960s onward. A trussed rafter is a self-contained triangulated frame. It spans from one external wall to the other, gable to gable, and it carries its own load without needing anything in the middle. Every truss lands on the two outer walls, full stop. Internal partitions beneath a trussed rafter roof are structurally irrelevant to the roof above them.

Contrast that with a traditional “cut” roof. In a cut roof, the main sloping rafters are supported partway along their span by horizontal timbers called purlins. Those purlins are in turn held up by angled struts, and those struts bear down onto something — usually an internal spine wall or a binder beam. There, the internal wall is doing real structural work. Remove it without replacing that support and the purlin sags, the rafters spread, and you’ll see it in the ceiling within months.

That distinction — trussed rafter versus cut roof — is the single most important thing to establish before anyone starts talking about steel beams.

The four things I read in the loft

You don’t need to be an engineer to understand what I was looking for. Here are the four checks that settled it on this job, all of them visible from a loft hatch with a torch.

1. Truss shape

The W-profile Fink trusses were immediately obvious — the distinctive triangulated webbing running between the top chords (the rafters) and the bottom chord (the ceiling joist). No traditional cut rafters, no loose timbers, no ad-hoc propping. The roof was exactly what a 1970s volume-build should be.

2. No purlins, no struts

A cut roof announces itself with heavy horizontal purlins running parallel to the ridge, propped by struts that angle down to a wall. There were none. The loft was clean — just the trusses, insulation, and the occasional water tank bracket. No struts means no load being transferred to internal walls.

3. No spliced ceiling joists over the wall lines

In a trussed rafter roof, the bottom chord of each truss is a single continuous timber running from external wall to external wall. If an internal wall were load-bearing, you’d often see the ceiling joists lapped or spliced directly over that wall — the wall acting as a mid-span support, the joists bearing onto it. On this job, the bottom chords were uninterrupted single members with no joint sitting over either partition. Classic non-load-bearing signature.

4. No truss node above either wall

Where a truss’s internal web members meet the bottom chord, you get a node point — a concentration of force. If a wall sits directly beneath a node, it could be acting as a reaction point for that truss. Neither wall on this job had a node above it. The trusses were reacting onto the external walls as designed, with no internal assistance.

The walls themselves confirmed the picture. They sounded hollow when tapped, felt light, and were consistent with 1970s Paramount-style partitioning — two plasterboard skins bonded to a honeycomb cardboard core. Zero structural capacity. These were never intended to carry anything.

The honest nuance: non-load-bearing doesn’t mean zero role

I want to be clear about something, because oversimplifying this causes problems. A partition wall that carries no roof load can still be doing a secondary job — stiffening a long ceiling span at mid-point, for instance, and preventing the bottom chords of the trusses from deflecting or the plasterboard from cracking over time.

This is why I recommended a phased approach on this job rather than demolishing both walls in a single day. Remove over two or three truss bays first. Pause. Watch for any deflection, new cracking, or movement in the ceiling over a few days before completing the work. If anything beyond hairline cracking appears — anything that opens or propagates — stop and get an engineer back on site before continuing. In this case, the phased removal went smoothly with no issues, and the full removal proceeded without incident.

It’s a belt-and-braces step, but it costs nothing except a little patience and it means you’re responding to what the building is actually telling you rather than assuming.

Building Regulations still apply — even without a beam

This is the compliance point that surprises some homeowners. No steel beam does not mean no Building Regulations. Removing an internal wall is a material alteration under the Building Regulations 2010 (Regulation 3), which means the work must not make the building less compliant with the relevant requirements than it was before.

Approved Document A (Structure) is the obvious one — you must not worsen the structural performance of the building. But merging a kitchen into an open-plan living and sleeping space also engages Approved Document B Volume 1, which deals with fire and smoke separation and inner-room escape routes. If the open-plan layout changes how smoke would travel in a fire, or removes a protected corridor, that needs to be addressed. Electrical circuits and gas pipework rerouting fall under Part P and Gas Safe requirements respectively.

The right step is to notify your Local Authority Building Control before the work starts, confirm what inspections they require, and keep a record of the loft inspection findings — including photographs — as part of the building notice submission. On this job, the absence of a steel beam actually simplified the Building Control process considerably, but the notification was still required and the fire separation question still needed answering.

What this means for your budget

Had the load-bearing assumption stood unchallenged on this job, the homeowner would have been looking at Eurocode 3 beam sizing calculations, padstone and bearing design, temporary propping, a structural engineer’s Building Control package, and the cost of the steel itself plus installation. All of that was avoided by reading the roof correctly first.

I’m not suggesting every internal wall removal turns out to be this straightforward. Many genuinely do need a steel beam — particularly in pre-1960s properties with cut roofs, in two-storey houses where upper floors bear onto internal walls, or where a wall carries a load-bearing partition from the floor above. But the point is that you shouldn’t assume, and your builder shouldn’t assume either. The assumption costs money when it’s wrong in one direction, and it costs structural integrity when it’s wrong in the other.

A loft inspection by a chartered engineer before any design work is commissioned is the most efficient way to answer the question. It’s a short visit, it’s relatively inexpensive compared to unnecessary steelwork, and it means every decision that follows is based on what the building actually is — not what someone assumed it might be.

When to call a structural engineer

Call a structural engineer before you remove any internal wall if you’re unsure whether it’s load-bearing, if your property was built before the 1970s trussed rafter era, if you can see purlins and struts in the loft, or if your builder is quoting for steel without having inspected the roof structure. You should also get professional input if the wall you’re removing runs parallel to the floor joists above (a different load-bearing scenario from the roof), if there’s any existing cracking near the wall, or if the property is a flat or maisonette where Party Wall Act considerations may also apply. A single inspection visit resolves most of these questions definitively and gives you a firm basis for whatever comes next.

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Need expert eyes on your project?

I am a Chartered Structural Engineer (CEng, MIStructE) based in Huddersfield. The Beam Doctor offers homeowners and builders:

• Steel beam (RSJ) calculations — Eurocode-compliant, Building Control-ready, in 5 working days. See all services and current fees →
• Defect investigation — I attend your property, inspect the cracking or movement, and give you a written opinion on the cause. The site visit is included in the price. See the fee bands →
• Structural Engineer’s Report — a signed desk-based opinion on a single structural concern, for a mortgage lender or an insurance claim. Request a report →
• On-site attendance — a Chartered Engineer at your property, tiered by duration. See site visit fees →

Current fees for every service are listed on the services page.

You’ve had a few quotes for your loft conversion and every builder seems to be specifying a steel beam — sometimes two. Before you sign anything, it’s worth asking a simple question: do you actually need that steel at all? In some cases the answer is no, and the difference between knowing and not knowing can run to thousands of pounds.

Key Takeaways

• Whether you need a steel beam in a loft conversion depends almost entirely on your roof type — not on a builder’s instinct or a standard quote template.
• In a bungalow or house with a trussed-rafter roof, the internal walls below the roof are very often non-load-bearing and can be removed without any steelwork.
• In a traditional cut or purlin roof, those same walls may be carrying real load from the roof structure — and that’s where a beam becomes necessary.
• A short inspection by a structural engineer is the single most cost-effective step you can take before committing to a specification.
• Getting this wrong in either direction costs money: unnecessary steelwork wastes it, while removing a load-bearing wall without support causes serious structural damage.

Why the question matters more than you might think

I see this situation regularly. A homeowner in West Yorkshire is planning a loft conversion, they’ve had two or three builder quotes, and every single one includes a steel beam — often described as an RSJ — to carry the roof load or open up the floor below. The quotes range from a few thousand pounds to considerably more, and the homeowner assumes the beam must be necessary because everyone is quoting for one.

Sometimes it is necessary. Sometimes it genuinely isn’t. The frustrating truth is that a builder quoting from a site visit of twenty minutes, without inspecting the loft space properly or understanding the roof construction, will often default to specifying steel because it’s the safe commercial choice for them. It covers their bases. It isn’t necessarily the right answer for your building.

The question of whether loft conversion load bearing walls are actually present in your property — and whether they’re doing any structural work — is not one you can answer by looking at a floor plan or listening to a builder’s assumption. It requires someone to look at the roof structure itself.

Two very different roof types, two very different answers

The single most important thing I check when I’m asked about a loft conversion is the roof type. There are two broad categories in UK residential buildings, and they behave completely differently structurally.

Trussed-rafter roofs

From roughly the 1960s onwards, most new houses and bungalows were built with factory-made trussed rafters. These are the W-shaped timber frames you’ll recognise if you’ve ever poked your head into a modern loft. The critical point is that trussed rafters are self-supporting. Each truss spans from external wall to external wall and carries its own load. The internal walls below — the partition walls dividing bedrooms, for example — are very often doing nothing structural at all. They’re just dividing space.

In a trussed-rafter bungalow, I’ve inspected properties where every internal wall could come out without a single piece of steelwork being required. No beam, no padstone, no temporary Acrow props during construction. Just careful removal and a tidy finish. That’s a fundamentally different job — and a fundamentally different budget — from what the quotes were suggesting.

Traditional cut or purlin roofs

Older properties — typically pre-1960s, though there are plenty of exceptions — tend to have what’s called a cut roof or a purlin roof. Here, the roof structure is built in situ from individual timbers: rafters, ridge boards, purlins, and hangers. Purlins are the horizontal timbers that run along the slope of the roof and support the rafters mid-span. Those purlins often bear onto internal walls, which means those walls are carrying real load from the roof above them.

If you remove an internal wall in a traditional cut roof without providing an alternative load path, the purlin loses its support, the rafters sag, and you have a serious structural problem. This is exactly the situation where a steel beam is warranted — sized and specified properly, bearing onto padstones, with Building Control sign-off.

What an inspection actually involves

When I attend a property to advise on a loft conversion, the first thing I do is get into the loft space. I want to see the roof structure with my own eyes. I’m looking at how the timbers are arranged, whether there are purlins and where they bear, whether I can see truss plates (the metal connector plates that are the hallmark of a factory-made truss), and what the internal walls below are actually connected to — if anything.

I’ll also look at the ceiling joists and floor structure, because a loft conversion changes the loading on those too, and that’s a separate question from the walls. But the roof type is the starting point. That inspection — which typically takes twenty minutes in the loft itself, plus time to discuss findings with the homeowner — is the thing that tells you which job you actually have.

Without it, you’re guessing. And when you’re guessing about loft conversion load bearing walls, you’re either spending money you don’t need to spend, or you’re about to create a structural defect that will cost far more to fix than the beam would have.

The cost of getting it wrong in either direction

I want to be direct about both failure modes here, because homeowners sometimes assume the risk only runs one way.

If you pay for steelwork you didn’t need, you’ve wasted money — potentially a significant amount — and added unnecessary complexity to your project. That’s frustrating, but it’s recoverable.

If you remove a load-bearing wall without providing support, the consequences are more serious. Roof spread, sagging rafters, cracking in the structure above and below — these are not cosmetic issues. Depending on how long the problem runs before it’s caught, remedial work can be substantially more expensive than the original beam specification would have been. And if it comes to light during a sale, it can affect your ability to sell the property at all without a structural engineer’s report confirming the defect has been properly remedied.

The inspection I’m describing isn’t a luxury. It’s the step that makes everything else sensible.

What happens after the inspection

If the inspection confirms your internal walls are non-load-bearing — as is common in trussed-rafter properties — I’ll tell you that clearly, in writing if needed. You can take that back to your builder and revise the specification accordingly. No beam required, no padstones, no structural calculations to submit to Building Control for that element of the work.

If the inspection shows that walls are carrying load from a purlin or other roof element, I’ll advise on what’s needed. That typically means designing a steel beam to carry the load, specifying the padstone bearing details, and producing structural calculations for Building Control. The calculations need to be Eurocode-compliant and submitted as part of your Building Regulations application — this isn’t optional, and it’s not something a builder can do on your behalf without an engineer’s input.

Either way, you leave the inspection knowing what you’re actually dealing with. That’s the point.

When to call a structural engineer

If you’re planning a loft conversion and anyone has mentioned removing internal walls — or if you’ve received quotes that include steelwork and you’re not sure whether it’s justified — call a structural engineer before you commit to a specification. The same applies if you’re buying a property where a loft conversion has already been done and you want to know whether it was carried out correctly. An engineer can assess the existing structure, confirm whether any load-bearing walls were properly dealt with, and provide the signed report that lenders and insurers sometimes require. Don’t rely on a builder’s assumption about your roof type. Get someone into the loft who knows what they’re looking at.

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Need expert eyes on your project?

I am a Chartered Structural Engineer (CEng, MIStructE) based in Huddersfield. The Beam Doctor offers homeowners and builders:

• Steel beam (RSJ) calculations — Eurocode-compliant, Building Control-ready, in 5 working days. See all services and current fees →
• Defect investigation — I attend your property, inspect the cracking or movement, and give you a written opinion on the cause. The site visit is included in the price. See the fee bands →
• Structural Engineer’s Report — a signed desk-based opinion on a single structural concern, for a mortgage lender or an insurance claim. Request a report →
• On-site attendance — a Chartered Engineer at your property, tiered by duration. See site visit fees →

Current fees for every service are listed on the services page.

You’ve decided to open up your ground floor — maybe knock the kitchen into the dining room, or create that open-plan living space you’ve been planning for years. Before anyone picks up a sledgehammer, there are a few things you genuinely need to understand first, and getting them right will save you time, money, and a very uncomfortable conversation with Building Control.

Key Takeaways

• Not every internal wall is load-bearing, but assuming it isn’t can have serious structural consequences — a proper assessment is always worth it.
• A structural engineer’s beam calculations must come before the builder starts, not after something goes wrong.
• Building Regulations approval under Part A (Structure) is a legal requirement for this type of work — not optional.
• Temporary propping during the knock-through is just as important as the permanent steel beam.
• If the wall is on a boundary with a neighbour, the Party Wall Act may also apply.

Is the Wall Actually Load-Bearing?

This is the first question every homeowner asks, and it’s a fair one. The honest answer is: you can’t tell just by looking at it, and neither can most builders. There are clues — a wall running at right angles to the floor joists, sitting on a foundation or a beam below, with another wall or roof structure sitting above it — but clues are not conclusions.

I’ve visited properties where a wall looked like a simple partition but was actually carrying the full weight of a bedroom floor above, plus a section of roof. I’ve also seen walls that looked substantial but turned out to be non-structural stud partitions added during a 1970s refurbishment. The difference between those two scenarios, from a structural point of view, is enormous.

A proper assessment means looking at the original construction of the house, checking what sits above and below the wall, understanding how the floor joists span, and — where possible — inspecting the loft space to see how the roof loads are distributed. That’s what a structural engineer does. A builder’s “quick look” is not a substitute for that analysis, and if something goes wrong, Building Control will want to know who signed off the structural design.

What the Wall Might Be Carrying

Load-bearing walls in a typical UK terraced or semi-detached house can be carrying several things at once. Floor joists from the room above may be bearing directly onto the wall’s head. A wall on the first floor may be sitting directly above the ground-floor wall you want to remove. The roof structure — whether it’s a traditional cut roof or a modern trussed rafter system — may be transferring loads down through the same load path.

This is why beam calculations are not a box-ticking exercise. When I work out the size of a steel beam (a universal beam section, sometimes still called an RSJ) for a knock-through, I’m calculating the combined load from all of those sources — dead loads from the structure itself, imposed loads from people and furniture, and any roof loads that travel down through the wall. Get the beam size wrong and you end up with a beam that deflects excessively, or worse, one that isn’t safe under full load.

The beam also needs adequate bearing at each end — usually onto a padstone, which is a block of dense concrete or engineering brick that spreads the point load from the beam end into the supporting wall or pier below. Padstone size is part of the structural calculation, not an afterthought.

Temporary Propping: The Part People Overlook

Before any masonry comes out, the structure above needs to be supported. This is done using Acrow props and a system of temporary needles or spreader beams — essentially a temporary load path that keeps the floor and wall above stable while the permanent steel is installed.

Inadequate propping is one of the most common causes of problems during knock-through work. I’ve seen cases where props were placed too far apart, or where the spreader beam above wasn’t stiff enough to distribute the load properly, leading to cracking in the plasterwork above — or worse, movement in the structure. The propping scheme needs to be thought through properly, ideally by the engineer who has done the beam calculations, so the builder knows exactly where to place the props and how to sequence the work.

This isn’t about being overly cautious. It’s about making sure the job goes smoothly and the builder isn’t left guessing during a critical phase of the works.

Building Regulations and Building Control Sign-Off

Removing a load-bearing wall is notifiable work under Part A (Structure) of the Building Regulations in England. That means you need Building Control involvement — either through your local authority or a private approved inspector. You cannot simply do the work and hope nobody notices. If you come to sell the property, your solicitor will ask for evidence of Building Regulations approval, and if it isn’t there, the sale can stall or fall through entirely.

The process is straightforward when it’s set up properly. The structural engineer produces calculations and a specification — covering the beam size, padstone details, propping requirements, and any other structural elements. Those documents are submitted to Building Control before work starts. A Building Control officer will inspect the works at key stages, typically when the beam is installed and before it’s boxed in. At the end, you receive a completion certificate, which is the document that confirms the work was done to the required standard.

Approved Document A provides the technical framework that Building Control uses to assess structural work. Your engineer’s calculations need to demonstrate compliance with that framework, which is why calculations from a chartered structural engineer carry weight with Building Control officers — they know the work has been done properly.

Party Wall Obligations in Terraces and Semis

If the wall you want to remove is a party wall — shared with a neighbouring property — you have additional legal obligations under the Party Wall etc. Act 1996. This applies in terraced houses and semis where the structural wall sits on or close to the boundary between two properties.

The Act requires you to serve written notice on your neighbour before the work begins, giving them the opportunity to consent or to appoint a party wall surveyor. This is separate from Building Regulations — you need both. The party wall process protects your neighbour’s interests and, frankly, it protects you too, by creating a formal record of the condition of the adjoining property before any work takes place.

If your neighbour consents in writing, the process is quick. If they don’t, a party wall award is drawn up by surveyors, which sets out how the work will be carried out and managed. It adds time and cost, but it’s a legal requirement and not something to skip.

What Does It Actually Cost?

I’m often asked about removing a load-bearing wall cost, and the honest answer is that it depends on several variables — the span of the opening, what’s sitting above the wall, whether the beam needs to be a single section or a compound arrangement, and the complexity of the propping required.

What I can tell you is that the structural engineering fees — beam calculations, padstone design, and Building Control submission documents — are a relatively small part of the overall project cost. The builder’s labour, the steel fabrication, the making-good of plasterwork and floor finishes, and any kitchen or joinery work that follows are typically the larger items. Cutting corners on the structural design to save a few hundred pounds rarely makes sense when the rest of the project budget runs to several thousand.

Getting the engineering right at the start also avoids the costly scenario of having to re-prop, re-specify, or redo work because Building Control has raised a query that wasn’t addressed in the original design.

When to Call a Structural Engineer

Call a structural engineer before your builder starts — ideally before you’ve even had the builder quote, so the scope of work is properly defined. If you’re not sure whether the wall is load-bearing, that’s reason enough to pick up the phone. If you know it is load-bearing and you’re ready to proceed, you need beam calculations and Building Control submission documents before anyone starts propping or cutting. And if the wall is shared with a neighbour, factor in the Party Wall Act timeline too. Getting a structural engineer involved early makes the whole project run more smoothly — for you, for your builder, and for Building Control.

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Need expert eyes on your project?

I am a Chartered Structural Engineer (CEng, MIStructE) based in Huddersfield. The Beam Doctor offers homeowners and builders:

• Steel beam (RSJ) calculations — Eurocode-compliant, Building Control-ready, in 5 working days. See all services and current fees →
• Defect investigation — I attend your property, inspect the cracking or movement, and give you a written opinion on the cause. The site visit is included in the price. See the fee bands →
• Structural Engineer’s Report — a signed desk-based opinion on a single structural concern, for a mortgage lender or an insurance claim. Request a report →
• On-site attendance — a Chartered Engineer at your property, tiered by duration. See site visit fees →

Current fees for every service are listed on the services page.

You’ve looked up into your loft, seen the space, and started imagining a bedroom or home office up there. But before you call an architect or a loft conversion company, there’s a question worth asking honestly: is the structure actually ready for that? Understanding the loft conversion structural requirements early saves you from expensive surprises halfway through a build.

Key Takeaways

• Your existing ceiling joists were never designed to carry people and furniture — a new structural floor is almost always required.
• If your roof was built with modern trussed rafters, cutting it open isn’t straightforward — an engineered scheme is needed to redistribute the loads.
• Steel beams are typically required at eaves level to carry the new floor, and again if you’re adding a dormer.
• A structural engineer produces the calculations and drawings that your builder and Building Control both need before work starts.
• Most lofts can be converted — it’s a question of getting the structure properly designed, not of whether it’s possible at all.

The biggest misconception: your ceiling joists aren’t a floor

This is the one I find myself explaining on almost every loft conversion enquiry. Homeowners look up at the loft floor — those timbers running across the ceiling of the room below — and assume they’re looking at the floor of the future room. They’re not. Those joists were sized by the original designer to do one job: hold up a plasterboard ceiling. That’s a light, static load. A habitable room is an entirely different proposition — people walking, furniture sitting, wardrobes standing full of clothes.

Building Regulations require a habitable floor to be designed for an imposed load of 1.5 kN/m² as a minimum for a domestic bedroom. The ceiling joists in most houses, particularly those built from the 1960s onwards, will be nowhere near capable of carrying that. They’re typically 50 × 100 mm or 50 × 125 mm timbers, spaced to suit the ceiling below, not a structural floor above.

What this means in practice is that a new structural floor almost always has to be formed. That’s not a problem — it’s just something to plan and design for from the outset, rather than discover when a builder starts probing around.

How the new floor is formed

The new floor joists are sized properly for their span and the loads they’ll carry. In a standard semi-detached or terraced house, the span from one external wall to the other is often too great for timber alone to handle economically, which is where steel beams come in.

The typical arrangement is a pair of steel beams — one each side — running along the eaves at the point where the roof slope meets the ceiling. The new floor joists then span between those steels. This keeps the depth of the floor construction reasonable and avoids the new structure eating into the headroom you’re relying on. The steels themselves sit on padstones — bearing plates, usually engineering brick or concrete — that spread the concentrated load from the beam end into the masonry wall below.

Getting those steels specified correctly matters. Too small and the beam deflects excessively; too large and you’ve wasted money and made installation harder than it needs to be. The calculations that determine the right section size, bearing length, and padstone specification are part of what a structural engineer produces for Building Control.

The make-or-break roof question: trussed or traditional?

Once the floor is sorted, the roof itself needs attention — and this is where the type of roof you have becomes critical.

Houses built from roughly the 1960s onwards are very likely to have a trussed rafter roof. These are the prefabricated timber frames you’ll recognise from the loft — W-shaped or Fink trusses, spaced at 600 mm centres, with diagonal web members running across the space you want to use. The reason those web members are there is structural: each one is doing a job, carrying tension or compression as part of the truss. You cannot simply cut them out to create headroom without causing the roof to fail.

A trussed roof can absolutely be converted — but it requires an engineered scheme. The loads that the trusses were carrying have to be redistributed through a new structural arrangement, typically involving ridge beams, purlin beams, and new rafters. This is design work that needs to be done by a structural engineer, not improvised on site.

Older houses — broadly pre-1960s, though there’s overlap — are more likely to have a traditional cut roof: individual rafters, a ridge board, purlins, and struts. These are generally more straightforward to open up because the structural elements are more visible and the load paths more easily modified. That doesn’t mean no engineering is needed, but the starting point is usually less complicated.

The first thing I do when assessing a loft conversion is establish which type of roof is present. It shapes everything that follows.

Dormers and the additional structural work they bring

Many loft conversions include a dormer — a box-like extension through the roof slope that creates extra headroom and floor area. Dormers are popular and often transformative for usable space, but they add structural complexity.

A dormer requires the existing rafters in that section of roof to be cut. Those rafters were carrying load from the roof covering down to the wall plate. Once you cut them, that load has to go somewhere else. Typically, trimmer rafters and a structural header beam are introduced to frame the dormer opening and carry the loads around it.

The dormer structure itself — its flat or pitched roof, its cheeks — also needs to be designed. If the dormer is large, a steel frame may be needed to support it. Again, this is calculation work that feeds directly into the Building Control submission.

What the structural engineer actually produces — and why Building Control needs it

Part A (Structure) of the Building Regulations requires that any building work — including a loft conversion — doesn’t impair the structural stability of the building. Building Control will want to see evidence that the structural alterations have been properly designed. That evidence comes in the form of structural calculations and drawings from a chartered structural engineer.

For a loft conversion, that typically means:

• Floor joist sizing calculations, showing the new timbers are adequate for the imposed and dead loads
• Steel beam calculations for the eaves beams and any dormer steels, including deflection checks
• Padstone and bearing calculations
• A structural scheme drawing showing how the roof alterations work, particularly for a trussed roof

Your builder needs these drawings to know what to order and how to build. Building Control needs them to sign off the work. Without them, the project stalls — or worse, work proceeds incorrectly and has to be undone.

One thing I’m clear about with homeowners: the structural engineering is one lane of the loft conversion process, not all of it. Fire safety — a protected stairway, escape windows, fire doors — is a Building Regulations requirement that sits with your architect and Building Control officer, not with me. I focus on making sure the structure is sound and properly documented. The fire strategy is a parallel conversation you need to have with your designer.

When to call a structural engineer

You should bring a structural engineer in early — ideally before you’ve committed to a contractor or finalised the design with your architect. The structural feasibility of the conversion, particularly if you have a trussed roof or are planning a large dormer, can influence the design significantly. Getting the engineering assessed at the start means your architect designs around reality, not around assumptions. If you’re at the stage of applying for Building Control approval, you’ll need the structural calculations as part of that submission. Don’t leave it until the builder is on site asking for drawings that don’t exist yet.

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Need expert eyes on your project?

I am a Chartered Structural Engineer (CEng, MIStructE) based in Huddersfield. The Beam Doctor offers homeowners and builders:

• Steel beam (RSJ) calculations — Eurocode-compliant, Building Control-ready, in 5 working days. See all services and current fees →
• Defect investigation — I attend your property, inspect the cracking or movement, and give you a written opinion on the cause. The site visit is included in the price. See the fee bands →
• Structural Engineer’s Report — a signed desk-based opinion on a single structural concern, for a mortgage lender or an insurance claim. Request a report →
• On-site attendance — a Chartered Engineer at your property, tiered by duration. See site visit fees →

Current fees for every service are listed on the services page.

You’ve just received your homebuyer’s survey and, buried in the report, there’s a recommendation to “seek further advice from a structural engineer.” Your stomach drops — and suddenly the purchase you’ve been excited about feels fragile. Take a breath: in most cases, this is a precaution, not a catastrophe, and a structural engineer’s report for house purchase is often quicker and more straightforward to obtain than you might expect.

Key Takeaways

• A surveyor flags concerns; a structural engineer diagnoses the cause and tells you whether it’s actually significant — these are two very different things.
• The majority of cracks flagged in homebuyer surveys turn out to be old, settled movement that poses no ongoing structural risk.
• Many structural engineer reports can be produced desk-based from your survey and photographs alone — no site visit required, which keeps costs down and turnaround fast.
• Speed matters: if a mortgage lender has imposed a retention, getting the right report quickly can be the difference between a purchase completing or collapsing.
• A signed structural engineer’s report gives your lender, solicitor, and insurer something concrete to act on — a verbal reassurance from a builder does not.

Why your survey flagged it in the first place

RICS surveyors — the professionals who carry out Level 2 homebuyer reports and Level 3 building surveys — are trained to identify and flag anything that might be structurally significant. That is exactly what they should do. But their role is observation and risk flagging, not structural diagnosis. When a surveyor writes “cracks noted to rear elevation — recommend further investigation by a structural engineer,” they are doing their job properly. They are not telling you the building is falling down.

The most common triggers I see are diagonal cracking at window or door corners, stepped cracking in brickwork, cracks at a party wall junction, or visible deflection in a lintel. Sometimes it’s a bulge in a wall, or evidence that a chimney breast has been removed without the surveyor being able to confirm adequate support was provided. Occasionally a lender — rather than the surveyor — flags the issue themselves and imposes a mortgage retention until a qualified structural engineer has signed off the property. In every one of these scenarios, the next step is the same: commission a structural engineer’s report.

What a structural engineer’s report actually is — and isn’t

There’s a lot of confusion about this, so let me be direct. A RICS homebuyer survey and a structural engineer’s report are fundamentally different documents produced by different professionals for different purposes.

The surveyor’s report is a broad condition survey of the whole property — roof, drainage, damp, windows, services, and structure. It covers everything at a relatively high level. When the surveyor reaches the limits of their expertise on a specific structural question, they refer you to a specialist. That specialist is me.

A structural engineer’s report focuses on the specific concern raised. I look at the cracking pattern, the location, the building’s age and construction type, any available history, and the photographs. I assess whether the movement is active or historic, whether it has a structural cause or a more benign one (thermal movement and minor settlement account for a very large proportion of what gets flagged), and I state clearly what — if anything — needs to be done about it. The report is signed by a Chartered Engineer, which is what your lender and solicitor need to see.

What the report is not is a repeat of the full building survey. It is a targeted, expert opinion on the structural question at hand.

The reassuring reality about cracking

I want to be honest with you here, because I think it helps to hear it plainly: the majority of cracks I am asked to assess turn out to be historic settlement that has long since stabilised. Old Victorian and Edwardian terraces in West Yorkshire — the kind of stock that makes up a huge proportion of the housing market in towns like Huddersfield, Halifax, and Dewsbury — have had 120-plus years to move, settle, and find equilibrium. Many of the cracks you see in these properties were formed decades ago and have not changed since.

That does not mean every crack is harmless. Active subsidence, inadequate support to a removed chimney breast, a failed lintel, or a wall that is genuinely out of plumb by a significant margin — these are real structural concerns that need addressing. But the point is that you cannot tell which category a crack falls into without engineering assessment. A surveyor cannot tell you. A builder definitely cannot tell you. That assessment is what the structural engineer’s report provides.

When I review a set of crack photographs and a survey extract, I am looking at crack width, pattern, and orientation; which materials are cracking and at which interfaces; whether there is any evidence of recent activity; and what the building’s construction and ground conditions suggest about likely behaviour. All of that analysis can often be done without setting foot on site.

Desk-based reports: faster and lower-cost than you think

This is probably the most practically useful thing I can tell you if you’re in the middle of a purchase. Many structural engineer reports for house purchase can be produced entirely desk-based — meaning I work from your RICS survey, the photographs taken during that survey, and any additional photographs you or your agent can provide. No site visit required.

This matters for two reasons. First, cost: a desk-based report is considerably less expensive than one requiring a site attendance. Second, speed: I can typically turn around a desk-based report in a matter of days rather than weeks. When your mortgage offer has an expiry date, or when a vendor is getting impatient, or when a lender’s retention is holding up a completion, that speed is not a luxury — it is essential.

I will always tell you honestly if the evidence warrants a site visit. Some cases genuinely do — where the crack pattern is ambiguous, where there is suspected active movement, or where the photographs simply don’t capture enough detail for a confident diagnosis. In those cases, an on-site attendance is the right call and I will say so. But many cases do not require it, and there is no point in adding cost and delay when the desk-based evidence is sufficient.

What the report contains and what happens next

A structural engineer’s report in this context will typically set out the specific concern identified in the survey, my assessment of the likely cause, whether I consider the issue to be structurally significant, and — where relevant — a remedial specification or recommendation. That last point matters: if remedial work is required, the report should tell your builder or contractor exactly what is needed, not just that “something should be done.”

Once you have the report, your solicitor can share it with the vendor’s solicitors. If the issue is minor, it may simply satisfy the lender and allow the purchase to proceed. If remedial work is needed, you have a documented specification that can form the basis of a price negotiation or a request that the vendor carries out the work prior to completion. Either way, you are in a much stronger position with a signed engineer’s report than without one.

If your lender has imposed a retention specifically pending a structural report, the report goes to the lender’s valuer or their panel. Again, a signed report from a Chartered Engineer — CEng, MIStructE — is what they are looking for.

When to call a structural engineer

If your homebuyer survey has recommended further structural investigation, or if your mortgage lender has flagged a structural concern and imposed a retention, you need a structural engineer’s report — not a builder’s opinion, not a second viewing, and not a wait-and-see approach. The same applies if you spotted something on your own viewing that concerned you: diagonal cracking, a wall that looks out of plumb, a sagging roofline, or signs that internal walls may have been removed without proper support. The sooner you commission the report, the sooner you have the information you need to make a decision — and the sooner your purchase can move forward.

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Need expert eyes on your project?

I am a Chartered Structural Engineer (CEng, MIStructE) based in Huddersfield. The Beam Doctor offers homeowners and builders:

• Steel beam (RSJ) calculations — Eurocode-compliant, Building Control-ready, in 5 working days. See all services and current fees →
• Defect investigation — I attend your property, inspect the cracking or movement, and give you a written opinion on the cause. The site visit is included in the price. See the fee bands →
• Structural Engineer’s Report — a signed desk-based opinion on a single structural concern, for a mortgage lender or an insurance claim. Request a report →
• On-site attendance — a Chartered Engineer at your property, tiered by duration. See site visit fees →

Current fees for every service are listed on the services page.

You’ve spotted a crack in your wall and your stomach has dropped. Before you call your insurer or start imagining underpinning bills, take a breath — the overwhelming majority of cracks in UK homes are completely harmless, caused by nothing more dramatic than plaster shrinkage, seasonal temperature swings, or settlement that finished decades ago. This post will give you a practical way to read what your cracks are actually telling you.

Key Takeaways

• Most cracks in walls are cosmetic — caused by thermal movement, plaster shrinkage, or old settlement — not subsidence.
• The BRE Digest 251 damage category scale (0–5) is the standard framework engineers use to gauge severity; categories 0–2 are generally cosmetic, category 3 and above warrant proper investigation.
• Warning signs that justify calling a structural engineer include cracks wider than roughly 3–5 mm, doors or windows that have started sticking, and any crack that is actively widening over time.
• True subsidence risk factors are specific: clay soils, large trees close to the building, and leaking drains. Without those, genuine subsidence is uncommon.
• A structural engineer diagnoses the cause and tells you whether a crack is structurally significant — often from clear photographs and a few measurements before any site visit is needed.

Why most cracks are nothing to worry about

I see a lot of worried homeowners, and the first thing I tell almost all of them is this: your house is not falling down. UK homes move — constantly and imperceptibly — in response to temperature, humidity, and loading. Plaster is brittle, mortar has a finite life, and timber frames dry out over years. All of that produces cracks, and virtually none of it is structurally significant.

The most common culprit I encounter is simple plaster shrinkage. A fresh plaster skim loses moisture as it cures and fine hairline cracks appear within months — sometimes weeks. They look alarming on a freshly decorated wall but they carry no structural meaning whatsoever. Similarly, thermal movement in a brick or block wall causes tiny cracks to open slightly in summer and close again in winter. If you see a hairline crack that seems to change with the seasons, that is almost certainly what you are looking at.

Long-finished settlement is another very common source of cracks in older properties. When a house is first built, the ground beneath it compresses under the new load. This settlement typically completes within the first few years of the building’s life, but the cracks it left behind can remain visible for the lifetime of the property. If a crack has been there for twenty years and hasn’t changed, it is a historical record of movement that is long over — not evidence of anything ongoing.

How to read your cracks: a practical guide

Before you call anyone, spend ten minutes examining the crack properly. The things I want to know when a homeowner contacts me are: how wide is it, where exactly does it sit, does it go through the full thickness of the wall, and has it changed recently?

Width

A crack you can barely see — under about 0.1 mm — is a hairline crack. Up to about 1 mm is still very fine. These are categories 0 and 1 on the BRE Digest 251 damage scale, and they are cosmetic. You can fill them with a little decorator’s filler and forget about them. Once a crack reaches 5 mm or more — roughly the width of a 5p coin — it moves into territory that warrants a proper look.

Pattern and location

Stepped cracks that follow the mortar joints in a staircase pattern through brickwork are the classic sign of differential movement — one part of the wall has moved relative to another. Diagonal cracks running from the corners of window or door openings are extremely common and usually indicate modest differential settlement or thermal movement around the lintel. Horizontal cracks in a brick wall, particularly at mid-height, can be more serious because they may indicate lateral pressure from retained soil or a failing wall tie — that pattern deserves attention.

Internal only, or inside and out?

A crack visible only in internal plaster is almost always a plaster or dry-lining issue. A crack that you can trace in both the internal plaster and the external brickwork, in the same position, tells you the full wall section has moved. That is a more meaningful finding and worth investigating further.

The BRE Digest 251 damage categories

BRE Digest 251 gives engineers and surveyors a consistent language for describing crack severity. It runs from category 0 (hairline cracks, negligible) through to category 5 (structural damage requiring major repair and possible partial rebuilding). As a rough guide:

• Categories 0–2 (up to about 5 mm wide): cosmetic damage. Redecoration or minor repointing is all that is needed.
• Category 3 (5–15 mm, or several cracks grouped together): moderate damage. Doors and windows may be sticking. A structural engineer should assess the cause.
• Categories 4–5 (15 mm and above, or cracks affecting structural integrity): severe to very severe. These require urgent professional input and likely significant remedial work.

In practice, the vast majority of cracks homeowners contact me about fall into categories 0–2. The scale is a useful anchor because it stops people catastrophising a 1 mm crack and, equally, stops them dismissing a 10 mm crack as cosmetic.

The real warning signs of subsidence

Genuine subsidence — ground movement beneath the foundations causing the structure above to drop or tilt — is far less common than the word suggests. When I am assessing whether cracks in walls could indicate subsidence, I am looking for a specific combination of factors.

The first is soil type. Clay soils shrink significantly when they dry out and swell when they rehydrate. In a dry summer, a clay subsoil can lose enough moisture to allow shallow foundations to drop by several millimetres. The second factor is trees. A large tree within roughly its own height of the building will extract significant moisture from clay soil, particularly in summer. The third is drainage. A leaking underground drain can wash fine material away from beneath a foundation, leaving a void. If your property sits on clay, has a large tree nearby, and you have cracks appearing or widening — that combination warrants investigation.

The warning signs I take most seriously are: cracks wider than 3–5 mm that you cannot explain by any other cause; doors or windows that have started sticking or jamming when they previously opened freely; and above all, cracks that are actively widening over time. That last point is the most important. A static crack, however wide, is a historical event. A crack that is growing is telling you something is still moving.

What your insurer does versus what a structural engineer does

These two things are often confused, and the confusion causes homeowners a lot of unnecessary stress. If you report cracking to your buildings insurer as a potential subsidence claim, their process typically involves monitoring — they will want to establish whether movement is ongoing before committing to any remedy. Monitoring can take months or longer. Underpinning, the remedy insurers sometimes fund in confirmed subsidence cases, is expensive and disruptive, and insurers will not authorise it without extensive evidence.

A structural engineer does something different and, in my view, more useful as a first step. I assess the cause of the cracking. I look at the crack pattern, the building’s age and construction, the ground conditions, the proximity of trees, and the drainage layout. I form a professional opinion on whether the cracking is structurally significant, what is most likely causing it, and what — if anything — needs to be done about it. That diagnosis can often be reached from clear photographs and a few measurements the homeowner provides before I even visit the site. It gives you an answer rather than a monitoring programme.

A structural engineer’s report also carries weight with insurers, mortgage lenders, and solicitors. If you are buying or selling a property with cracking, a signed report from a chartered engineer explaining the cause and confirming it is not structurally significant is far more useful than a monitoring schedule.

When to call a structural engineer

Call me — or another chartered structural engineer — if you have cracks wider than roughly 5 mm, if cracks are appearing in both the internal and external faces of the same wall, if doors or windows have started sticking, or if you can see a crack is widening over weeks or months. You should also get professional input before buying a property where cracking is visible, or if your insurer has raised subsidence as a possibility. In many cases I can give you a meaningful initial view from good photographs alone — which means you get an answer quickly and without necessarily incurring the cost of a site visit straight away.

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Need expert eyes on your project?

I am a Chartered Structural Engineer (CEng, MIStructE) based in Huddersfield. The Beam Doctor offers homeowners and builders:

• Steel beam (RSJ) calculations — Eurocode-compliant, Building Control-ready, in 5 working days. See all services and current fees →
• Defect investigation — I attend your property, inspect the cracking or movement, and give you a written opinion on the cause. The site visit is included in the price. See the fee bands →
• Structural Engineer’s Report — a signed desk-based opinion on a single structural concern, for a mortgage lender or an insurance claim. Request a report →
• On-site attendance — a Chartered Engineer at your property, tiered by duration. See site visit fees →

Current fees for every service are listed on the services page.