Statement regarding the weathering of PVC-U Rainwater Goods
PVC-U rainwater systems (gutters, downpipes and accessories) have been manufactured and used in the UK since the 1950's and are now the most popular option for roof drainage.
Under permanent exposure to ultraviolet light (sunlight), the service life of a well-stabilised and correctly installed PVC-U rainwater system will exceed 50 years.
In normal building service conditions, PVC-U has no known degradation mechanism other than oxidation caused by the combined effects of ultraviolet radiation and atmospheric oxygen. For rainwater systems, which are by their nature exposed for long periods, carefully selected additives and stabilisers are blended with the polymer during manufacture to minimise the impact of these environmental conditions on the surface condition and colour of pipework.
Rainwater products are manufactured to either BS EN 607 or BS EN 12200-1 and subjected to accelerated exposure to ultraviolet light. Before and after exposure, the products are tested for colour change on fittings and pipes and tensile impact strength for pipes. The BPF Pipes Group and its members strongly advise that compliance with these standards is certified by a third-party certification scheme.
PVC-U rainwater systems do not need specific maintenance but benefit from cleaning to keep the building looking smart. Mild detergents used for window and fascia cleaning can also be used for gutters and downpipes. There is no need to provide additional protection by painting, although this is an option available to the property owner.
BS EN 607: Eaves gutters and fittings made of PVC-U. Definitions, requirements and testing.
BS EN 12200-1: Plastics rainwater piping systems for above ground external use. PVC-U. Specifications for pipes, fittings and the system.