http://www.barrisroofing.co.uk/grp-fibreglass-roofs-weybridge/

A properly laid fibreglass roof also known as GRP Roofing, will last for at least 30 years with no measurable deterioration. The roof must be laid onto a dry deck in dry conditions at a temperature not below 5°C. The resins and top coats should be suitable for use in GRP Roofing.