GRP Flat Roofing – What is it and how does it work?

GRP Flat Roofing – What is it and how does it work?

What does GRP stand for?

grp roofGRP stands for ‘Glass Reinforced Plastic’ a material made from a polyester resin, which is reinforced by chopped strand mat glass fibres to form a GRP laminate. It is a very popular composite material to use because not only is it very strong but also surprisingly light. Invented by Russel Games in 1938 it was originally used on boats and water containers but has since been developed and become one of the most widely used materials in the construction industry. Today’s GRP is far superior to that of the forties and fifties, although the principal is still the same – a durable, lightweight, flexible, fully reinforced and waterproof material capable of being moulded to any shape.

How does GRP work?

Our GRP flat roofing systems combine a number of materials including OSB3 board decking, Topseal resin, fibreglass matting, Topseal durable topcoat and Topseal fibreglass preformed trims to create a roof that’s not only tough and impact resistant but also attractive and pleasing to the eye.

It all starts with the bare ceiling joists and the attachment of quality 18mm OSB3 decking with insulation to help reduce heat loss or without insulation for a cold roof build up (your installer will take into account Part L building regulations when specifying your Topseal roof). Specially formed Topseal GRP edge trims are then fitted to finish the sides, also giving them strength. A Topseal GRP Laminate, made up of the fibreglass matting and Topseal resin, this is designed to be very hard wearing and is bonded to the decking. A 450 csm (chop strand mat) is standard for roofs with very little or no foot traffic. If your roof will see a high level of foot traffic, like a balcony would then the Heavy Duty 600 csm will be recommended, which is part of the Topseal HD system. The roof is then beautifully finished with a Topseal topcoat, dark admirality grey is the standard and most popular topcoat colour but any RAL colour is available, this finishes your roof perfectly and your will now have a roof that is watertight and a 25 year or 30 year guarantee depending on which Topseal system you chose to be installed on your project.

As one of the UK’s leading GRP roofing companies, we offer some of the most efficient GRP flat roofing solutions available for domestic or commercial roofs, whether they’re modern or traditional.

A Topseal fibreglass roof will only be installed by Topseal trained and approved installers. You can be sure that your project will be in safe hands with us. Should you be interested in becoming an installer, check out our leading GRP Roofing Course.

If you would like to find out more about our GRP roofing systems and how they could benefit your home or commercial premises, please feel free to get in touch by calling us on 08000 831 094. All enquiries are welcome.





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