Glass-fibre reinforced plastic, commonly abbreviated GRP or FRP, is a composite drainage material made from glass fibres encapsulated in polyester or vinyl ester resin. It is used for large diameter sewers, culverts and trenchless rehabilitation applications across the UK, manufactured under BS EN 14364. GRP pipes are lightweight relative to concrete and offer excellent resistance to chemical attack from septic flows. They are identifiable by their smooth, often glossy interior and distinctive layered cross-section. In Greater London, GRP is occasionally specified for Thames Water trunk sewer rehabilitation works and large industrial drainage, where in-situ wrapping of the existing pipe with GRP segments provides structural renewal without full excavation. The material is also used for septic tank construction and small private wastewater treatment plants in peri-urban locations.
Glass-fibre reinforced plastic (GRP)
Composite drainage pipe of glass fibres in polyester resin, used for large diameter sewers.
