Pipe rerounding is normally performed on structurally weak pipes. Older pipe networks laid between around the 1950’s to 1970’s, are most likely to be made of pitch fibre. It is a cheap material, that’s easy to handle due to it’s lightness. Pitch fibre pipes are made from wood cellulose impregnated with refined inert coal tar pitch under high pressure. The main issue with pitch fibre pipework being its uncertain lifespan. As a result, pitch fibre pipes are prone to;
- Weakening and deterioration with age.
- Chemical erosion (not suitable for carrying hot water or waste that includes oils, fats or petroleum).
- Blistering that causes obstructions.
- Leakages that attract roots.
- Leakages that cause erosion and subsidence.
- Further damage due to normal forms of maintenance.