GRP is a composite material made up of polyester resin, reinforced with glass fibres.  It is protected from UV erosion by a surface coating consisting of a gel or laminate.  The composite is extruded and set over forming moulds to match specific roofing profiles. 

GRP can often be used as translucent sheeting or it can be supplied with a clear, or opaque gel coat to the weather surface to provide a high level of corrosion resistance to aggressive atmospheres, where coated metal or even non-ferrous metals may not perform as required.

Examples of use can be found in extreme environments such as wool scouring plants, fertilizer stores, tanneries, acid plants and smelters, abattoirs, compost plants, galvanizing plants, and buildings in harsh geothermal areas.

Where an entire roof is clad in GRP, (rather than individual sheets separated by metal sheets as in a typical case of translucent sheeting), it affects the trafficability and safety requirements. If a GRP roof is required to be accessible, it can be manufactured incorporating woven roving reinforcement into the resin matrix to make it trafficable. Another option would be to install stainless steel safety mesh under the roof cladding, if required.

Clause Number: 
Draft Clause: