Do I need a structural report when buying a house?
Most buyers do not need a structural engineer. Some do, and finding out late can delay an exchange or cost money. Here is how to tell which group you are in.
The short answer
Most buyers need a RICS Level 2 or Level 3 survey rather than a structural engineer's report. You need a structural report when the survey or the lender's valuation flags a structural concern, such as cracking, movement, a removed chimney breast, a knocked-through wall or a bowing wall, when the lender makes one a condition of the mortgage, or when the property has a history of subsidence or underpinning. Get it before you exchange contracts, while you can still renegotiate or walk away.
The cost of a structural report is small compared with the price of a London home, and it answers a question that a survey deliberately leaves open. The cost of skipping one only shows up later, when you try to remortgage, make an insurance claim or sell to a buyer whose lender asks the same question.
Valuation, survey and structural report: the difference
A mortgage valuation is for the lender. It confirms the property is adequate security for the loan and is not a detailed inspection. If the valuer sees something that could affect value, such as cracking, they may make the offer conditional on a structural engineer's report.
A RICS home survey is for you. Level 2 suits conventional houses in reasonable condition, while Level 3 suits older, larger or altered properties. It covers the whole building's condition and will flag structural symptoms, often recommending further investigation.
A structural engineer's report answers the structural question directly: what is causing the defect, whether it is still moving, how significant it is and what needs doing. The difference between a structural engineer and a building surveyor is worth understanding before you book either.
Common triggers in London purchases
London's housing stock is old and has been altered many times. These are the issues that most often lead a surveyor or valuer to ask for an engineer.
- Chimney breasts removed downstairs with no visible support for the breast or stack above
- Rooms knocked through with no Building Control completion certificate
- Cracking around bay windows, which often move independently of the main house
- Previous subsidence claims or underpinning, sometimes only partly documented
- Sloping floors and out-of-level door heads in Victorian terraces
- Bulging or leaning flank walls on end-of-terrace houses
- Loft conversions or extensions without approval paperwork
- Cracks where an extension meets the original house
Timing it within the conveyancing process
Order the survey early, ideally as soon as your offer is accepted, so any structural recommendation leaves time for an engineer's visit. The engineer needs access, which your conveyancer or the estate agent arranges with the seller. Lenders will often hold the mortgage offer until a requested report is received, so a late booking can push back exchange.
If a lender has asked for the report, send the engineer the valuer's wording. Some lenders also need the report addressed to them, or need to be able to rely on it, so mention this when you enquire.
Tell the engineer if there is a deadline. Exchange dates in chains are often fixed before anyone has booked the report, and knowing the date lets the visit and report be planned around it. Our typical turnaround is 10 working days, confirmed with your fee before anything is booked.
What the report tells you
A good structural report gives you a clear view on four things: the likely cause, whether movement is historic or active, how significant it is, and what action is recommended. That may be no action, minor repairs, monitoring or further investigation. Where one issue has been flagged, a Specific Structural Inspection report is usually the right level. Where there are several, a broader inspection covers them together.
All our structural inspection reports are signed off by a chartered engineer who is a Member of the Institution of Civil Engineers (MICE). The report does not value the property or give repair costs, though it gives you the information a builder needs to price repairs.
Read the limitations section carefully. A visual inspection cannot see inside walls or under fitted floors, and where something hidden matters the report will say so. A recommendation to open up or monitor is not a vague answer. It tells you precisely what remains uncertain, which you can then raise with the seller.
When paperwork for alterations is missing
Your solicitor will ask the seller for Building Control certificates for any structural alterations. If they are missing, there are a few routes. Indemnity insurance is common and quick, but it covers the legal risk of enforcement, not whether the work is safe, and it is usually invalidated if anyone contacts the council about the work first.
If you want to know the work is sound, an engineer can inspect it. For a single item, a structural letter of comfort may satisfy a lender or solicitor. Where the work needs to be properly regularised with Building Control, a retrospective structural assessment checks the work, specifies any upgrades and supports the application. Either way, agree with your solicitor which route you are taking before anyone approaches the council.
Using the findings
A structural report gives you facts to negotiate with. If repairs are needed, you can ask for a price reduction, ask the seller to carry out the work before completion, or agree a retention. If the report confirms the cracking is historic and stable, you can proceed with confidence, and you have a document to hand to your own buyer one day.
Occasionally the report shows the problem is bigger than expected, for example active subsidence that has not been dealt with. Walking away is a legitimate outcome. It is far better to learn that now than after completion.
Whatever you decide, keep the report with your property documents. It records the condition of the structure when you bought, which is useful if new cracking appears later, if you make an insurance claim, or when you come to sell.
Frequently asked questions
Who pays for a structural report when buying a house?
Usually the buyer, because the report is commissioned to protect the buyer and satisfy the buyer's lender. Occasionally a seller commissions one in advance to answer known questions, which can help a sale move faster. Either way, make sure the report is addressed to the right person, because a lender may only accept a report it can rely on.
Can I rely on the seller's existing structural report?
It is useful background, but it was written for the seller and may be out of date. Your lender may not accept a report addressed to someone else. You can ask the original engineer whether they will extend reliance to you, or commission your own inspection, which can be quicker when the previous report is old or the property has changed since.
What happens if the structural report finds subsidence?
It depends on whether the movement is historic or active. Historic, stabilised movement may simply need cosmetic repair and is often acceptable to lenders. Active subsidence usually needs the cause dealt with, often through an insurance claim, before a lender will proceed. Ask the seller about previous claims, as insurers will want to know and it affects future cover.
Do I need a structural report for a flat?
Sometimes. If the valuer or surveyor flags cracking, removed walls or a sagging floor within the flat, an engineer's report will usually be needed. Issues in the main structure, such as the front elevation or the roof, are normally the freeholder's responsibility, but they still affect you through service charges. The engineer may need access to communal areas, arranged through the managing agent.