HDPE pipe, made from high-density polyethylene, is a tough, semi-flexible plastic used for soil stacks in commercial buildings, adopted rising mains and specialist drainage applications. Joints are normally made by electrofusion or butt-welding, creating a homogeneous chemical bond that is fully sealed against root ingress and infiltration. UK installations are typically to BS EN 1519 for above ground and BS EN 12666 for underground use. HDPE is identifiable by its black or dark grey appearance, smooth interior and welded rather than socketed joints. The pipe accommodates ground movement well, making it suitable for poor-bearing soils. While more expensive than PVC-U, HDPE is often specified for tall residential developments in London where acoustic and durability requirements exceed those for a standard domestic stack.
HDPE pipe (high-density polyethylene)
Tough black plastic pipe used for above ground stacks and adopted sewer rising mains.
