Selling a House With RAAC Concrete: A 2026 UK Seller's Guide

By Lisa Hayes · 24 July 2026

Yes, you can sell a house that contains RAAC. But go in with your eyes open. Reinforced autoclaved aerated concrete can knock a valuation, spook mortgage lenders and shrink your pool of buyers, so the route you pick matters more than it would on an ordinary sale. This guide covers how to find out whether you're even affected, what RAAC does to a sale in practice, and the realistic ways to sell without being backed into a corner.

What is RAAC, and why has it suddenly become a problem?

RAAC stands for reinforced autoclaved aerated concrete. Picture an Aero bar rendered in grey concrete and you're not far off. It's made from sand, lime and cement, whipped through with aluminium powder so a chemical reaction fills it with thousands of tiny air bubbles, then baked in a steam oven called an autoclave. The result is roughly 70% air. Steel rods are cast in to give it strength, and that's the "reinforced" part.

Builders loved it in the post-war decades for good reasons. It was light, well-insulating, fire resistant and quick to install. Big ready-made planks could be craned into place without waiting for wet concrete to cure. So it went into thousands of flat roofs on schools, hospitals, civic buildings, factories and shops, and into some homes, particularly council-built estates where the same design was repeated street after street.

Here's the catch. RAAC is not the same durable stuff the Romans used. It's weak in tension, it hates getting wet, and the steel reinforcement can corrode or sit in the wrong place. Structural engineers have long warned it was only ever meant to last a few decades, and much of what's still standing went in during the 1960s and 1970s. Then in 2019 two school roofs, in Kent and Bolton, partially collapsed. That shattered the comfortable assumption that RAAC would age gracefully, and it triggered the wave of surveys, closures and headlines you've probably seen since.

The reason it frightens engineers is how it fails. A timber beam usually sags and groans before it gives way. RAAC can go through what's called shear failure, a sudden slicing action at the point where the plank rests on the wall, with little or no warning. That's what happened in Kent and Bolton. On a flat roof, the classic red flag is "ponding", where rainwater collects in puddles instead of draining. The water adds weight, the plank bends a little more, it holds more water, and so the cycle turns.

One thing worth holding onto before you panic: not every plank in a roof is necessarily dangerous. Assessments are done plank by plank, and in some cases only a single panel is at risk. Finding RAAC is a reason to act, not a reason to lie awake.

Does my house even have RAAC?

Most people worrying about this don't actually have it. The number of homes built with RAAC is small compared with the total housing stock. But small is no comfort if yours is one of them, so let's work out how likely you are to be affected.

Age and shape are the first clues. If your home is a Victorian villa or a 1930s semi with a pitched, tiled roof, RAAC is very unlikely unless someone bolted on a flat-roofed extension later. The candidates are post-war buildings, roughly 1950s to early 1990s, with a flat or shallow-pitched roof, especially where the house is one of a run of near-identical properties on an estate. A deep timber fascia board around the roofline is another tell. And if your home was converted from a former school, office, clinic or other public building, you should satisfy yourself either way.

You cannot confirm RAAC just by squinting at the roof from the pavement, because the planks are hidden under felt or asphalt on top and plaster below. If you can get a safe look underneath, RAAC shows up as grey or whitish planks about 600mm wide with a distinctive V-shaped groove between them. The surface is textured, and it scores easily with a sharp blade where ordinary concrete wouldn't. On a broken edge you'll see that unmistakable bubbly texture.

A word of caution before you go poking holes in ceilings. Some textured coatings from that era contain asbestos, so if you're in any doubt at all, stop and get a professional in. The moment you genuinely suspect RAAC, the right call is a chartered building surveyor or a chartered structural engineer, not a general builder and definitely not a bloke on a forum. RICS keeps a directory at ricsfirms.com, and the Institution of Structural Engineers has a "find an engineer" tool. It's also worth asking your local authority whether nearby homes of the same type are known to contain it, because councils have been surveying their own stock for exactly this.

What does RAAC actually do to a sale?

Three things, mostly: it can lower the valuation, it can make lenders nervous, and it can thin out your buyers. Let's take them in turn, because the details decide how you should sell.

On valuation, RICS is clear that RAAC can affect a valuer's professional opinion of value. If a surveyor spots it, or has reason to suspect it, during their normal visual inspection, they can down tools and request an independent specialist report before they'll put a figure on the property at all. The valuer won't assess the condition of the RAAC themselves. They pass that to a structural engineer, and the engineer's findings feed back into the number. A clean report saying the panels are sound and well-maintained is a very different starting point from one flagging shear risk.

On buyers, you're up against nerves as much as facts. "Crumbling concrete" has been front-page news, and plenty of buyers will simply walk rather than learn what a bearing end is. Cash buyers and investors are far more relaxed, because they can factor a repair into the price and they aren't beholden to a lender's checklist.

Which brings us to the big one.

Can you get a mortgage on a house with RAAC?

Sometimes yes, sometimes no, and here's the honest version rather than the scary one. RICS states plainly that a property with RAAC is not necessarily unsuitable for a mortgage. Lending policies vary from lender to lender and shift over time. What kills deals is not the word "RAAC" on its own, it's uncertainty. A valuer working to a cautious lender's instructions who finds unexplained RAAC and no supporting paperwork will play safe, and that's when you get a nil valuation or a "not suitable security" letter.

So the single most useful thing you can do is remove the uncertainty before a buyer's surveyor ever turns up.

Keep every scrap of documentation: dates of any re-roofing, records of alterations, monitoring reports, engineers' letters, and details of any remedial work. When a buyer is remortgaging or purchasing, that pack answers the valuer's and solicitor's questions in one go. If your report is genuinely reassuring, a mainstream mortgage is far from impossible. If it isn't, you at least know where you stand, and you can price and plan accordingly rather than watching sale after sale collapse at the survey stage. On the harder cases, our guide to selling an unmortgageable house covers the cash and auction routes in more depth.

Will my home insurance pay to fix it?

Probably not, and this trips a lot of people up. A standard buildings policy pays out for an "insurable event": a storm, a fire, a flood, a one-off accident. The mere existence of a material that's known to be problematic isn't an event. If your RAAC roof is still doing its job and hasn't failed, insurers take the view that nothing has actually happened, so there's nothing to claim for.

If a panel genuinely collapses, your policy might cover the accidental damage that results, but not necessarily the cost of stripping out the undamaged planks around it, which is usually where the real money goes. Policy wording differs, so ring your insurer or broker and ask the specific question. Don't assume you're covered, and don't assume you're not.

What are my realistic options for selling?

You've essentially got four routes, and choosing between them is a trade-off between the price you achieve and the certainty and speed you get. There's no universally "right" answer. It depends on your report, your finances and how quickly you need to move.

An open-market sale through an agent gives you the best shot at the highest price, but only if the fundamentals stack up. If your report is clean and priced sensibly, a cash buyer or a homeowner with an understanding lender may well go for it. Be honest with your agent from day one, and pick one who won't hide the RAAC and hope, because that just burns weeks before a survey exposes it. If you're weighing agents at all, our rundown of the best house-buying companies is a useful sense-check on who actually delivers.

Auction suits properties that scare high-street buyers but excite investors. RAAC houses often fall squarely into that camp. The buyer does their due diligence up front, the sale becomes legally binding on the fall of the hammer, and completion typically follows within a month or so. You'll likely take less than a perfect open-market price, but you swap that for near-certainty. Just budget for auction fees and don't set a fantasy reserve.

A cash house-buying company is the quickest exit. A genuine cash buyer isn't relying on a mortgage, so a lender's RAAC policy is irrelevant to them, and a sale can complete in a fortnight or so. The trade-off is price: expect an offer below market value, because the buyer is pricing in the repair and the risk. That can be entirely worth it if you need out fast, you're avoiding a repair bill you can't fund, or the stress simply isn't worth it. The important thing is not to take the first number you're given. Compare offers, check reviews, and make sure the company is a member of the National Association of Property Buyers and registered with a redress scheme like The Property Ombudsman. Our guides to cash house buyers and what "we buy any house" really means below market value break down what a fair discount actually looks like.

The Aberdeen warning: what Torry tells every RAAC owner

If you want a real-world lesson in how this can go wrong, look at Balnagask in Torry, Aberdeen. It's the most significant residential RAAC case in the UK, and it's still playing out.

• ~504homes affected in Balnagask, Torry
• 138of them privately owned
• £150m+estimated demolition and rebuild cost
• £15,000maximum home loss payment offered

Around 366 council homes and 138 privately owned ones were found to contain RAAC in their roof panels. Aberdeen City Council decided to demolish and rebuild the estate, at a cost put at more than £150 million. For the private owners, the council offered a voluntary acquisition: market value plus a home loss payment of up to £15,000. The sting was in the detail. The offer had the cost of repairing the RAAC roof deducted from it, and residents reckoned that repair figure ran into tens of thousands, which threatened to leave people in negative equity on homes they'd owned for years. Some owners refused, held out past deadlines, and a property-swap scheme was offered as an alternative, with the council lining up a batch of homes for residents to bid on.

The lesson isn't "councils are villains". It's that a RAAC problem left to a single buyer with all the leverage ends badly for the owner. The Torry residents who fared least well were those with the fewest options. Which is the entire argument for getting your own report, understanding your true position, and testing the open market and independent buyers before you accept anyone's take-it-or-leave-it figure.

Do I have to tell buyers about RAAC?

Once you know, yes. This isn't optional and it isn't a grey area.

When you sell, you complete the TA6 Property Information Form, and you're bound by the Consumer Protection from Unfair Trading Regulations and the law on misrepresentation. Knowingly concealing something as material as RAAC, or answering the form dishonestly, exposes you to the sale collapsing, the buyer pulling out, or a claim against you after completion. A buyer who discovers hidden RAAC six months in has every reason to come after you, and the fact you kept a survey in a drawer will not help you.

Honesty is also the commercially smart play. Disclosing RAAC up front, with a structural report attached, lets you control the story. You present it as a known, assessed, documented condition rather than letting a buyer's surveyor "discover" it and imagine the worst. If you're unsure what has to go on the form, our plain-English guide to what you must legally disclose when selling spells it out. And if some of the terminology here is new, the property jargon explainer is worth a look.

What will it cost to put right, and should I fix it or sell as-is?

There's no single number, because it depends on how much RAAC you have, how bad it is, and what the engineer recommends. RICS sets out three broad routes once RAAC is confirmed: monitoring, on a planned schedule of inspections; reinforcement or repair, propping and strengthening the affected planks; or full replacement of the panels, which is the gold standard and the most expensive. Monitoring might cost you a few hundred pounds a year. Replacing a roof deck can run to tens of thousands, as the Torry residents found.

So should you spend the money or sell as-is? Here's my honest take.

Cash and auction buyers exist precisely because "sell as-is" is a legitimate choice. You're effectively handing the repair project, and its risk, to someone better placed to take it on, in exchange for a lower price. For a lot of owners that's a sensible trade, not a defeat.

Can I sue the original builder?

Almost certainly not, if the house is old. Most RAAC buildings went up decades ago, well outside any window for a claim, so realistically that door is shut. There's a narrow exception: if your home was converted to residential use more recently, the Defective Premises Act 1972 might apply, and the limitation periods for defective-building claims were extended after Grenfell under the Building Safety Act 2022. This is genuinely complicated legal ground, so if you think you might have a case, talk to a solicitor who specialises in construction or property litigation. Don't count on it as your escape route, and don't let the hope of a claim stop you dealing with the sale in front of you.

What to do right now: a step-by-step plan

If you think you're affected, work through this in order rather than jumping straight to panic-selling.

1. Confirm it. Instruct a chartered building surveyor or chartered structural engineer to establish whether RAAC is present and, if so, what condition it's in. Ask the council whether neighbouring homes of your type are known to have it.
2. Get it in writing. A dated, detailed structural report is your single most valuable document. It drives the valuation, reassures lenders and buyers, and protects you legally.
3. Gather the paper trail. Pull together roofing history, alterations, maintenance records and any past engineers' letters into one pack.
4. Get the safety position clear. If the engineer flags an immediate risk, act on their advice first. Nothing below matters more than not being under a roof that could fail.
5. Price it honestly. Get a realistic sense of value both with the RAAC disclosed and, if relevant, after repair. A free, no-obligation valuation is a sensible starting point.
6. Choose your route. Weigh open market against auction against a cash sale using the trade-offs above, matched to your report and your timeline.
7. Compare, don't settle. Whichever route you pick, get more than one offer or opinion. The Torry story is what happens when an owner has only one buyer.

RAAC is a serious problem, but it isn't a sentence. Homes with it do sell, every week, once the owner knows what they're dealing with and stops negotiating blind. Get the report, tell the truth, understand your options, and make the buyers compete for the privilege.

If you'd like to see what independent, mortgage-free buyers would actually offer for your property, RAAC and all, you can compare offers here with no obligation and no pressure. Knowing your real options is the whole point. From there, the decision stays yours.