The short answer
A building survey does not cover anything that is concealed, inaccessible or requires testing. It will not look behind walls, under fitted carpets or floorboards, inside the structure, or into sealed voids; it does not test services (no live electrical test, no boiler firing, no flow test on drains); it does not provide a valuation by default; and it does not cover legal matters such as title, boundaries, planning consents, leases or restrictive covenants — those are your conveyancer's job. It also does not confirm asbestos, knotweed, subsidence or contamination — it flags suspicion and points to specialists. It is a non-intrusive visual inspection, so its honesty lies in stating clearly what could not be seen and recommending the right follow-up.
Knowing what a survey leaves out is as useful as knowing what it includes. Here is the honest list of exclusions and who covers each gap.
Key exclusions at a glance
- Concealed areasBehind walls, under floors
- Services testingNo EICR, gas, or drain test
- ValuationNot included by default
- Legal / titleConveyancer, not surveyor
- Definitive hazardsAsbestos/knotweed flagged only
Concealed and inaccessible areas
The single biggest limitation is that the inspection is non-intrusive. The surveyor will not lift fitted carpets or fixed floor coverings, will not open up walls or ceilings, will not move heavy furniture or stored belongings, and will not dismantle the structure. That means concealed timbers, hidden wiring and pipework, the inside of cavity walls, foundations, the membrane under a flat roof, and floor voids are all outside direct view. Where access is blocked — a locked outbuilding, a sealed loft, a boarded floor — the report says so. This is not the surveyor being lazy; it is the defined scope of a visual survey, and the report manages the risk by flagging the area and recommending opening-up or a specialist where the evidence justifies it.
Services, hazards and valuation
Because services are not tested, the survey cannot certify the electrics, gas, heating or drainage. And because the inspection is visual, it cannot confirm certain hazards — it raises them as suspected and routes you to the right specialist. The table sets out the most common gaps and who fills them.
| Not covered / not confirmed | Why | Who covers it |
|---|---|---|
| Electrical safety | Not tested | EICR — qualified electrician |
| Boiler / gas safety | Not tested | Gas Safe engineer |
| Underground drains | Not visible | CCTV drain survey |
| Asbestos presence | Needs sampling | Asbestos surveyor |
| Market valuation | Not default scope | Valuer / lender survey |
Indicative exclusions and their specialists. Sources: RICS; HomeOwners Alliance.
Legal, planning and other matters
A building survey is about physical condition, not legal standing. It does not investigate title, ownership, boundaries on paper, restrictive covenants, rights of way, planning permissions or building regulation approvals, lease terms, or service charge liabilities — these are matters for your conveyancer or solicitor and the searches they run. Nor does the survey assess flood risk, ground contamination or radon beyond noting obvious indicators; dedicated environmental searches cover those. It also will not value the property for a mortgage — that is the lender's valuation, a separate and much lighter inspection. Reading these exclusions alongside the survey helps you assemble the full picture: condition from the surveyor, legal from the solicitor, and specialist tests for anything flagged.
Frequently asked questions
Does a building survey include a valuation?
Not by default. A Level 3 building survey focuses on condition. A valuation can sometimes be added as an extra, but it is separate from the lender's mortgage valuation, which is a lighter inspection done for the bank, not the buyer.
Does the survey cover legal issues like boundaries or planning?
No. Title, boundaries, covenants, rights of way, planning and building regulation consents are legal matters for your conveyancer and their searches, not for the surveyor, who assesses physical condition only.
Why does the survey not just open up the walls?
Because it is a non-intrusive inspection by agreement — opening up risks damage and is beyond the agreed scope. Where evidence justifies it, the surveyor recommends targeted opening-up or a specialist investigation as a follow-up.
Sources & further reading
Figures on this page are typical UK ranges drawn from published sources and depend on the specific property and survey level. They are guidance, not a quotation.