The essential first step before any repair or recoating
Planning to repair or recoat your fibreglass roof? Cleaning it first is the single most important thing you can do. A clean surface means your new coating will bond properly and last for years. A dirty one means it won’t. The good news? It’s really straightforward. Here’s how to do it in four simple steps
Step 1: Sweep Off Loose Debris
Use a stiff brush or broom to clear leaves, dirt, moss and grit. Work from the top down. That’s it – nothing fancy.
Step 2: Treat Any Green or Black Growth
Got algae, moss or slippery patches? Lightly wet the roof, apply a biocide cleaner, leave it to work, then scrub stubborn spots with a stiff brush.
Step 3: Rinse Thoroughly
Rinse the whole roof with clean water. A pressure washer works well but keep the lance at a safe distance. Make sure no dirty residue is left behind.
Step 4: Let It Dry Completely
This is crucial. Your roof must be completely dry before you apply any coating or sealant. In good weather this usually takes a few hours.
Now Inspect Your Roof
Once it’s clean you’ll be able to see the true condition of the surface. Look out for hairline cracks, pinholes, worn patches, or old repairs that are breaking down. This will help you decide whether you just need a fresh coating or some repairs first.
What Next?
Roof looks good, just tired or weathered? Our GRP Roof Restoration Coating goes on in one coat, needs no primer, and gives you another 10–15 years of protection. Just paint or roll it on.
Found cracks or pinholes? Apply a PU sealant to fill them, then coat straight over the top – you don’t even need to wait for the sealant to dry. We sell repair kits with everything included.
Found holes? A SpeedPatch sticks on in minutes and cures rock hard in daylight. Then coat over the top.
Weak or soft areas? Our reinforcement kits include GlassMat fabric that you embed into the coating for extra strength.
Quick Tips
- Always clean before repairing or coating – it’s the most important step
- Never apply coatings to a damp roof
- Avoid household bleach or detergents – use a proper biocide cleaner
- Pick a dry day, ideally above 10°C