Flat Roof Replacement in Basingstoke

Walk any of the estates and the pattern is obvious: a flat-roofed garage attached to the side or standing in a block behind the houses, a flat-roofed utility or kitchen extension across the back, and a flat canopy over the front door. The dormer bungalows around Kempshott and Oakley add flat dormer tops to the list. All of them were built as cold roofs, meaning the insulation sat at ceiling level and the deck above it stayed cold and damp — the reason so many of them rotted from underneath before the felt failed on top.

That is the part worth changing when you replace one. Modern practice under BS 6229 puts rigid insulation above the deck instead, so the whole structure sits on the warm side and condensation has nowhere to form.

2026 installed rates for domestic work in Basingstoke, including deck checks and edge trims. Small roofs price higher per m² because set-up costs the same whatever the size.

Flat roofs almost never fail in the middle. They fail at upstands, at trims, at the outlet, and where a fall was never built in so water sits until it finds a way through. Ponding is the clearest sign: if there is still standing water on your roof two days after rain, the fall is wrong and no membrane will fix that permanently.

So a replacement here means firrings cut to give a genuine fall of at least 1:80 after deflection, upstands taken 150mm above finished level, trims mechanically fixed and lapped in the right order, and an outlet sized for the area rather than whatever the old one was. That is what BS 6229 asks for and it is the difference between a flat roof you forget about and one you keep thinking about.