I have spent the last 12 years inspecting and replacing roofs across Sussex, and garage flat roofs in Hove are among the most frequent calls I get. Most property owners only notice a problem when water starts dripping onto their car or stored belongings. The reality is that by the time water breaches the internal ceiling, the timber decking has likely been absorbing moisture for months. If you have an aging felt roof on your garage, it is fighting a losing battle against Hove’s coastal wind uplift, salt air, and constant thermal movement.
Why Traditional Garage Flat Roofs Fail in Hove
Standard oxidized bitumen felts installed 15 or 20 years ago simply are not designed to withstand our coastal microclimate.
Thermal Movement and Coastal Exposure
Your garage roof takes a beating from the sun. The constant cycle of heating during the day and rapid cooling at night causes significant thermal movement. Older, inflexible felt expands and contracts until it inevitably suffers from surface crazing and structural cracking. Add Hove’s coastal salt air to the mix, and the protective mineral granules on cheap felt degrade rapidly, exposing the vulnerable bitumen beneath to destructive UV rays.
Decking Failure and Capillary Action
A frequent issue I diagnose on detached and semi-detached garages in Hove is poor edge detailing. When the perimeter drip edges fail or are improperly installed, capillary action draws rainwater back underneath the felt. This trapped moisture rots the OSB or plywood decking. Once the structural deck loses its integrity, the roof begins to sag, leading to severe water pooling (ponding) which accelerates the entire failure process. If you notice pooling water or suspect rot, it is time to review your garage flat roof replacement options before the timber structure completely collapses.
My Approach: SBS-Modified Bitumen for Outbuildings
I do not patch dying roofs; I replace them with systems designed to last. For uninsulated outbuildings like garages, I strictly use high-performance SBS (Styrene Butadiene Styrene) modified bitumen torch-on felt.
Unlike traditional felt, SBS is infused with synthetic rubber. This gives the membrane incredible elasticity. When the temperature drops on a freezing January night in Hove, an SBS roof flexes with the building structure rather than snapping.
The Installation Process
When I strip a garage flat roof, I completely remove the old, saturated coverings down to the joists to inspect for hidden timber rot. The rebuild process then includes:
- Structural Decking: Installing new 18mm OSB3 structural boards to ensure a rigid, load-bearing base without deflections.
- Underlay & Vapor Control: Applying a robust carrier membrane to manage breathability and prevent interstitial condensation within the garage.
- High-Performance Cap Sheet: Torch-welding the SBS mineral cap sheet, ensuring a seamless, monolithic bond at all laps and upstands to eliminate wind uplift risks.
- Edge Detailing: Upgrading fascia trims and drip edges to physically break capillary action and direct water efficiently into the guttering.
If your garage is attached to the house and shares a wall, I also inspect the lead flashings. Often, moisture bridges the gap between the house brickwork and the garage roof. If a sudden structural breach is threatening the interior of your property, you can arrange an urgent leak assessment to mitigate the damage.
Transparent Pricing for Hove Property Owners
I believe in absolute transparency, which is why I do not hide my pricing behind prolonged sales calls. Now that you understand the technical reasons behind your garage roof failure, you can skip the guesswork. Use the instant online calculator on my website to get a precise, no-commitment cost estimate for your garage roof replacement in under 30 seconds. From there, we can arrange a free site survey where I will diagnose the root cause in person and provide a fixed quote.