Common flat roof problems and how they're fixed
Ponding, blistering, splits and soft decking explained — plus the main flat roof systems compared.
Ponding water
Standing water after rain means the roof doesn't have enough fall. It speeds up wear and is usually fixed by adjusting the falls when the roof is re-covered.
Blisters, cracks and splits
Felt roofs blister and crack as they age in the sun. Small areas can be patched, but widespread cracking means the covering is near the end of its life.
Choosing a replacement
EPDM rubber is a single seamless sheet that suits most domestic roofs. GRP fibreglass gives a hard, walkable finish. Modern torch-on felt is a good-value option. The right choice depends on size, shape and how the roof is used.