How to Properly Fix a Garage Roof: From Minor Leaks to Timber Rot
If you need to fix a garage roof in Sussex, the first thing I assess isn’t just the surface felt—it is how long the water has been penetrating the structure. Garage flat roofs are highly exposed to coastal winds, thermal movement, and UV degradation. When the old covering fails, water ingress is immediate. But the real problem lies underneath.
The Structural Reality of Prolonged Leaks
Many homeowners ignore a minor drip in the garage because it isn’t the main house. This is a costly mistake. Once moisture breaches the waterproof membrane, capillary action pulls water deep into the timber decking (OSB or plywood) and the supporting joists. If the leak has been active for a long time, simply torching a new layer of felt over the top is terrible trade practice. The trapped moisture will cause aggressive timber rot, leading to a sagging roof and eventual structural failure.
Half-Day Repairs vs. Full Replacements
If you catch the leak early, a complete structural replacement isn’t always necessary. For localized failures, such as split upstands, thermal blistering, or edge detailing separation, I offer a standardized half-day repair slot. This is usually more than enough time to strip back the damage, address the underlying issue, and apply a high-performance SBS-modified bitumen patch. You can easily schedule this through my urgent leak booking service.
However, if the decking feels spongy underfoot or the joists are visibly water-stained and soft, the structural timber must be replaced. I never cover up rotting wood, as it guarantees failure down the line.
Transparent, Pinpoint-Accurate Pricing
Figuring out the cost for replacing decking and structural joists might sound complicated, but it really isn’t. Structurally speaking, garage roofs are the most straightforward type of roof to fix. They are highly standardized—almost like carbon copies of one another in traditional UK construction. Because the process is so predictable, you can calculate the exact garage roof replacement cost right on my website.
My online calculator handles the complexities of timber and decking replacement effortlessly. You input your dimensions and select the structural upgrades, and it generates an instant, fixed price. Because garage roofs are so standard, the calculator is extremely precise. The price you see is the price you pay—I don’t need to bump up the quote after my physical site survey. Skip the wait for traditional hidden-fee quotes, use the calculator, and let’s get your garage watertight permanently.