Roofs and flat roofs
What is a mansard roof, and which part should you ask about if the survey is brief?
A mansard has a steep lower slope and a shallow upper slope, so it is two coverings and a junction, not one field of tiles. Leaks favour the junction, the dormers in the steep slope, and the gutters in the valley between them. Ask which of those the surveyor could actually see.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
Mansards are common on some London and urban houses, often with dormers in the steep face. The steep slope may be tile or slate. The shallow top may be a different material and may be invisible from the street. A ground-level look sees the steep face. It does not see ponding on the crown. Inside, stains at ceiling level can come from that crown or from a dormer cheek.
A RICS home survey records access. If the crown was not seen, the report should not read as a clean bill for the whole mansard. Ask a roofer who can get to the crown if the rating is serious. There is no standard mansard price in the RICS consumer guide. Quote the slope that is actually failing.
What should you ask your surveyor?
- Did you see the shallow crown, or only the steep face from the street?
- Are the two slopes the same material?
- Where is the staining inside, relative to the junction?
What are the typical next steps?
- Do not price a new steep slope because the crown was not inspected.
- Ask whether scaffold or a hatch is needed before you accept a roof quote.
- Keep dormers as their own line in any quote.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
Is a gambrel the same word?
People mix the names. Ask the surveyor which slopes they mean rather than debating the label. The junction is the point.
Can you insure a mansard as a flat roof?
That is an insurer’s question about the shallow part. The survey does not bind the insurer. Show them the report and ask.