Pitch fibre pipe is a drainage material made from compressed wood pulp impregnated with coal tar pitch, manufactured between roughly 1940 and 1975. It was widely installed in postwar UK housing across London and the home counties as a lower-cost alternative to clay. The pipe is identifiable by its dark brown to black colour, thin wall section and tendency to deform into an oval cross-section as it ages, a defect known as blistering or delamination. CCTV survey footage typically reveals a soft, deformed bore with peeling internal layers. Pitch fibre is no longer manufactured and is generally considered beyond economic repair, with full replacement by PVC-U or CIPP relining recommended where structural integrity has failed. Vendor information packs for older properties should reference pitch fibre presence so buyers can plan remedial works.
Pitch fibre pipe
Compressed wood pulp drainage pipe impregnated with coal tar, common from 1940s to 1970s.
