Roofs and flat roofs
Concrete tiles cover a Victorian roof that the neighbours still have in slate. What extra weight has the survey not calculated, and what consent has it not checked?
The survey has not calculated the extra weight of the concrete tiles, and it has not checked whether consent was obtained for the change. A Victorian roof that the neighbours still have in slate now carries concrete tiles, which are a heavier covering than the slate the roof was built with. The inspection can see the tiles. It cannot weigh them by looking, and it cannot say the rafters were sized for that load. It has also not searched the consent history.
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?
Changing slate to concrete is common, and plenty of roofs carry it, but the gap here is what was not done. Extra weight is a question for the timbers, the battens and the walls, not a guess from the street. Whether the change needed consent or building-control approval is a paper question. The survey has recorded concrete tiles beside neighbours who still have slate. It has not calculated a load, and it has not approved the covering or refused it.
Ask a structural engineer or a roofing surveyor whether these timbers can carry the concrete tiles, which is a calculation this report has not made. Ask the solicitor whether any consent record exists for the change of covering. Do not treat the neighbour's slate as proof this roof is overstressed, and do not treat the tiles as proof it is fine. The survey has named the covering. It has not approved it.
What should you ask your surveyor?
- Has the extra weight of the concrete tiles been left uncalculated?
- Has any consent for the change from slate been left unchecked?
- Are the neighbouring roofs still slate, as context only?
What are the typical next steps?
- Treat weight and consent as two checks the survey has not done.
- Ask an engineer whether the timbers can carry the concrete tiles.
- Ask the solicitor whether a consent record exists for the change.
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
If the loft rafters look straight, has the weight been proved acceptable?
No. Straight rafters are not a calculation of the extra weight. Concrete tiles are heavier than the slate this Victorian roof was built with, and the survey has not worked out that load. A fair line today does not check consent either. Both questions remain open until someone does the work the inspection did not do.
Does a missing consent record, by itself, strip the tiles off?
No. The survey has not checked consent, which means the paper is unknown, not that a breach has been proved. The solicitor has to see whether any approval exists. The weight question is separate and also uncalculated. Neither gap is an instruction to strip the roof, and neither is a clearance.