Nobody can price your roof from an article — and you should be sceptical of anyone who prices it from a phone call. What an article can do is explain what moves the number, so a quotation makes sense when you get one and comparisons between quotes are fair.
The four things that set the price
1. The covering. The spread is wide: concrete tile is the economical end, clay costs more, and natural slate sits at the top — with the price gap partly repaid by lifespan (see how long each covering lasts). The covering also drives the labour: small plain tiles and individually nailed slates simply take longer to lay than large interlocking tiles.
2. The roof itself. Area, obviously — but complexity more than people expect. Hips, valleys, dormers and chimneys all add cut tiles, leadwork and time; a plain rectangular gable-to-gable roof of the same footprint is meaningfully cheaper than a hipped roof with two dormers.
3. Access. Scaffolding is a real fraction of any re-roof, and difficult access — conservatories below, shared drives, height — moves it. It's also not the place to economise: proper access is a legal requirement and the precondition for careful work.
4. What's found underneath. Timbers are the honest unknown. A good quotation prices the foreseeable (visible sag, known damp history) and states a clear process for the genuinely unforeseeable — agreed with you at cost before it's done, never sprung on the final bill.
Reading a quotation
An itemised quote should let you see: the covering specified (brand and grade, not just "tiles"), the membrane and battens, ridge and verge treatment (mortar or dry-fix), leadwork, scaffold, and waste disposal — old roofs weigh tonnes and skips aren't free. If two quotes are far apart, the specification is almost always where the difference lives: lighter membrane, mortared rather than dry-fixed edges, or an overlay masquerading as a re-roof.
Repair first?
One more honest question before spending replacement money: does the roof actually need it? A surprising number of "you need a new roof" verdicts are really one failed valley or a run of slipped tiles. Our guide to repair versus replacement covers how to tell — and a replacement quotation from us always says plainly if we think a repair would serve you better.