Flat Roofing in Sussex
A flat roof over an extension, garage or dormer needs reliable drainage as well as a sound waterproof covering. SENTRY repairs and replaces flat roofs across Sussex after checking the surface, deck and outlets together.
Flat roof repairs and replacement
A damp patch near the edge of a room may have started at a rooflight, wall upstand or rainwater outlet. Water can travel beneath a flat roof covering before it appears inside. Ponding after rain raises questions about falls and drainage, but it does not by itself show whether the waterproof layer or deck has failed.
A split or small opening in an otherwise sound covering may be repairable. A soft deck or moisture spread beneath the surface changes the picture: another patch or a fresh top layer may leave the problem in place. We check the affected build-up before discussing repair or replacement.
GRP, EPDM and felt each behave differently around rooflights, edges and wall junctions. The best fit for a garage, extension or dormer depends on the shape of the roof, how it drains, access and how the space is used. We explain the system being proposed and how its waterproofing finishes at those vulnerable details.
A flat roof over a heated room must manage condensation as well as rain. Insulation and vapour control beneath the covering need to suit the structure and the way the room is used. These hidden details matter as much as the finish you can see from outside.
Surfaces, falls and outlets
Repairs to leaks and failed edges
GRP, EPDM and felt options
Outlet, deck and roof-edge assessment
The outlet belongs to the waterproof layer
Water leaves through a small opening in the covering. The membrane or surface finish must meet the outlet correctly, or rain can reach the deck even when the open roof surface is sound.
Ask about flat roofingQuestions about flat roofing
Does standing water always mean a flat roof has failed?
Not always, but prolonged ponding can reveal poor falls or drainage and may shorten the life of some systems. It is worth assessing with the roof's construction in mind.
Can a flat roof be repaired instead of replaced?
A local repair may be viable if the surrounding system and deck are sound. Widespread defects or trapped moisture may point toward replacement.
Which flat roofing material is best for an extension?
GRP, EPDM and felt can each be suitable. The roof's shape, deck, movement, access, outlets and detailing determine which system makes sense. The choice should follow an assessment of the particular extension.
Why does my flat roof hold water after rain?
Standing water can result from inadequate falls, a blocked outlet or movement in the deck. Some surface water may drain slowly, but persistent ponding deserves a closer look at the roof's construction and drainage route.