The weather and temperature play a large role in the life of a fibreglass roofer, so you always need to have one eye on the sky before getting started.

Planning Ahead

Both the OSB boards and the GRP roofing materials don't cope well with water of any kind falling on them from the sky. Before you start doing anything get the weather from either a local radio station, online or just by going outside and looking up.

Have cover on standby

Heavy rain on a partially cured roof will inhibit the cure and turn the resin white which means stripping back and starting again, so always have a polythene cover on site and quickly accessible so you can throw over the entire roof. The polythene cover will protect the resin without sticking and will just peel off when the resin has cured.

Protect the decking

Never leave the boards bare, always try and get the base layer down and cured in good time. The new deck will soak moisture in like a sponge making laminating impossible. If you have to leave the boards bare then securely cover overnight adding timbers between the deck and cover to allow air movement.


Temperature also plays a large part in a fibreglass roof, too cold and the resin system will take longer to cure too hot and the resin system will cure really quick so you have to be aware and adapt your process to the changing conditions.

You can optimise the GRP roofing materials to work better in different temperatures by adjusting resin system and catalyst. The Fibrelast base resin and finishing topcoat system can be ordered in an LT (Low Temperature) version which will allow curing down to 0°c.