Flat roof replacement, before and after

The before photograph is what most failed flat roofs look like once the felt is peeled back: chipboard that has turned to compost, insulation that is holding water like a sponge, and joists that have been wet for years. Patching the felt on top of that is pointless, which is why we re-deck rather than overlay.

The other photographs show the sequence on flat roofs like this one: new joists or firrings where needed to give the roof a fall, a new OSB3 deck, insulation to the regulations where the room below is heated, and a three-layer torch-on felt system with a lead edge detail against the wall and a drip into the gutter.

Before and after

BeforeAfter

Before and after on a rear extension: rotten chipboard deck and wet insulation stripped out, then re-decked and finished in torch-on felt.

Photos from the job

Roofer laying the OSB deck for a new flat roof New torch-on felt flat roof with insulation and a lead edge detail

Services on this job

• Flat roofs
• Roof repairs