Selling a house with a history of subsidence and underpinning is harder than selling a standard property. We won’t pretend otherwise. But it’s not the disaster that some sellers fear when they first start researching the situation, and the difference between a smooth sale and a stalled one comes down to preparation, honesty, and choosing the right route to market.
We’ve bought hundreds of previously underpinned properties over the years, and we’ve also helped plenty of sellers who tried the open market route first, got six months in, watched it fall through, and came to us afterwards. So we have a clear view of what actually works in this market and what tends to waste your time.
How Much Does An Underpinned House Sell For?
A previously underpinned house typically sells for 10% to 20% less than an equivalent property with no subsidence history. The discount reflects buyer caution rather than any active structural concern, and it persists for many years after the work was completed regardless of how thorough the original repair was. That’s the price of the historical record, and there’s no realistic way around it.
The Disclosure Requirement
The other thing to accept early is that you have to disclose everything. The TA6 Property Information Form asks specifically about subsidence, structural movement, insurance claims (including refused claims), and any building works. Lying or omitting information here is a breach of the form and a breach of the Consumer Protection from Unfair Trading Regulations 2008, and if a buyer discovers it after completion, they can sue you for the difference in value plus legal costs. We’ve seen people lose £40,000 or more this way. Just be honest from the start.
With those two things accepted, your sale becomes manageable. Most underpinned houses do sell, the prices are below equivalent properties but they’re not zero, and the right preparation makes the difference between a buyer who walks away at survey stage and one who proceeds with confidence.
The Documentation You Need to Have Ready
Before you put the property on the market, you should have a complete documentation pack assembled. Buyers and their lenders will ask for all of this anyway, and having it ready upfront dramatically reduces the time spent answering queries and chasing paperwork during the sale process.
The Structural and Building Control Documents
The structural engineer’s original report identifying the subsidence is the starting point. This should describe what was found, what the cause was, and what was recommended. If the report isn’t in your hands, your insurance company or the engineering firm that did the work should be able to provide a copy.
The underpinning specification and Building Control sign-off is the next critical document. Building Control approval (issued by either the local authority or an approved inspector) confirms that the work was carried out to a satisfactory standard and complied with Part A of the Building Regulations. Without this, your buyer’s solicitor will struggle to confirm that the property is mortgageable.
Insurance and Guarantee Documents
The insurance claim documentation, if the work was funded through an insurance claim, includes the claim itself, the settlement details, and any monitoring reports that preceded the work. Buyers and their lenders will want to see that the claim was properly resolved and that the structural cause was definitively addressed.
Any guarantee or warranty from the underpinning contractor, typically running 10 to 20 years from the date of completion. Some guarantees are transferable to subsequent owners and add real value to your sale, while others terminate at change of ownership. Check the specific terms and provide whatever documentation exists.
Monitoring and Current Insurance
You’ll need recent monitoring reports, if any, demonstrating that movement has stopped since the work was completed. These aren’t always available but they’re powerful evidence for buyers and their lenders if you have them.
Updated buildings insurance details showing that the property is currently insured and that the existing policy covers the property in its post-underpinning condition. Some buyers will want to see that they can transfer or replace the policy easily.
The Mortgage Reality
The Narrower Lender Pool
Buyers using mortgages face a narrower lender pool when buying a previously underpinned property than they would for a standard purchase. Some mainstream lenders will lend without issue if the work is fully documented and the monitoring period has clearly demonstrated stability; others apply restrictions like reduced LTV caps or require additional structural surveys. A few decline regardless of documentation.
This narrower lender pool affects you as the seller in two ways. First, your buyer pool is smaller because some potential buyers will be filtered out by their mortgage situation. Second, the buyers who do progress are more likely to encounter lender-driven complications late in the process, which is why fall-throughs are more common on previously underpinned properties than on standard ones.
The Practical Caution
The practical implication is that you should be cautious about accepting an offer from a buyer whose mortgage situation isn’t fully confirmed before exchange. We’ve seen plenty of sales fall through at week 8 or week 10 because the lender’s surveyor flagged the subsidence history and the lender then withdrew or imposed conditions the buyer couldn’t meet.
How to Price the Property
Starting From the Comparable
Pricing matters more for previously underpinned properties than for standard ones, because the discount needs to reflect both the structural history and the narrower buyer pool you’re working with.
The starting point is the value an equivalent property without subsidence history would achieve in your area, which you can establish through Land Registry sold price data and comparable listings on Rightmove and Zoopla. From that figure, the 10% to 20% subsidence discount typically applies, with the exact level depending on factors like the time elapsed since the work was completed (longer is better), the quality of the documentation (better documentation supports a lower discount), the cause of the original subsidence (clay shrinkage from removed trees tends to be easier to price than mining-related movement), and whether neighbouring properties have any history of similar issues.
The Cost of Overpricing
If your estate agent suggests a price that doesn’t reflect this discount, the property will sit on the market without selling, viewings will be sparse, and the eventual sale price will probably be lower than if you’d priced realistically from the start. Properties that have been on the market for several months at unrealistic prices typically end up selling at heavier discounts than properties priced correctly from the outset.
The Marketing Approach
The Two Main Options
You have two basic options for marketing a previously underpinned property: full open market through a high street estate agent, or direct to specialist buyers who actively purchase properties with subsidence history.
The open market route can work if you have full documentation, a competitive price, and the time to wait through what’s typically a 4 to 9 month process with a higher than usual chance of fall-throughs. The agents who handle these properties well are usually those who specialise in older properties or have experience with non-standard situations, rather than the high-volume agents who tend to focus on standard sales.
The Direct Sale Trade-Off
The direct sale route is faster and more certain but produces a lower headline price. You’re typically looking at 70% to 85% of the open market value (which is itself already discounted for the subsidence history), which feels harsh on paper but often produces a similar net outcome once you account for the time saved, the avoided estate agent fees, and the certainty of completion.
For sellers who specifically need a fast or certain sale, the direct route usually makes sense. Common situations where it works best include needing to relocate quickly, dealing with inheritance, splitting assets in a divorce, avoiding repossession, or simply not wanting to spend the next year managing a complicated open market sale.
The Specific Pitfalls to Avoid
Disclosure and Timeline
Don’t try to hide the underpinning history. The TA6 form, the buyer’s solicitor’s enquiries, the lender’s surveyor, the buyer’s structural survey, and the title documents will all surface the history regardless of what you do, and trying to conceal it just creates legal liability and breaks the trust that the sale depends on.
Don’t underestimate how long the sale will take. Subsidence properties typically need longer marketing periods, more viewings, and more buyer enquiries before a successful sale, so if you’re working to a specific timeline you should start earlier than you would for a standard sale.
Fall-Throughs and Lowball Offers
Don’t assume your first buyer is your buyer. Fall-throughs are more common on these properties, particularly at survey or lender stage, so it’s worth keeping the property on the market until exchange and being prepared to start the process again if the first buyer drops out.
Don’t accept lowball offers from non-specialist cash buyers. Some buyers will use the subsidence history as a justification for offers significantly below what a specialist buyer would pay. If you’re considering the cash sale route, get offers from several genuine specialists rather than accepting the first one that arrives.
Selling Direct to a Cash Buyer
If the open market route doesn’t suit your circumstances, selling directly to a cash house buyer experienced with previously underpinned properties typically completes in seven days with all legal fees and surveys covered. We’ve handled hundreds of these purchases, so we understand what the documentation looks like, what the historical context typically is, and how to price the property fairly given the construction history.
The offer you’ll receive will be below the open market figure (typically 70% to 85% of the post-subsidence open market value), but the trade-off is genuine speed, certainty of completion, no fall-through risk, and no estate agent fees. For many sellers in this specific situation, that net outcome is genuinely competitive once you account for what the open market would actually deliver after a six-to-nine-month process.
The Bottom Line
A previously underpinned house can be sold, and most are sold every year across the UK. The keys are having complete documentation, pricing realistically, choosing a marketing approach that fits your specific circumstances, and being honest about the property’s history throughout the process. If the timeline pressure is high or the open market route has already failed, a direct sale to a specialist cash buyer typically produces a faster, more certain outcome.
FAQs
Do I have to disclose previous underpinning when selling?
Yes, absolutely. The TA6 Property Information Form asks specifically about subsidence, structural movement, insurance claims, and building works. Not disclosing this is a breach of the form and exposes you to legal action from the buyer after completion.
How much will I get for a previously underpinned house?
On the open market, typically 10% to 20% below an equivalent property without subsidence history. Through a specialist cash buyer, typically 70% to 85% of that already-discounted open market value, traded against speed and certainty.
Can I sell a previously underpinned house with a mortgage on it?
Yes, the existing mortgage just gets redeemed at completion from the sale proceeds exactly like a standard sale. The complication isn’t with your existing mortgage but with potential buyers’ mortgages, where the lender pool is narrower.
How long will it take to sell a previously underpinned house?
On the open market, typically 4 to 9 months from listing to completion, with a higher than usual chance of fall-throughs along the way. Through specialist cash buyers, typically 7 to 28 days regardless of subsidence history.
Do I need a new structural survey before selling?
Not strictly required, but recent monitoring reports or a current structural survey can substantially strengthen your position with buyers and their lenders. If the original underpinning was many years ago, an updated survey often pays back its cost through a stronger sale.
