What material are PDCs made of?
The predominant material used for PDC’s prior to the Second World War was vitrified clay pipe. Each section of pipe was usually two to four feet (0.6m to 1.2m) in length. The pipes were joined together with bell and spigots. Many types of materials over the years were used to try to seal the pipes from root intrusion. Most, if not all, were ineffective over the long term. Roots will naturally seek out the moisture in the pipes. A vast majority of the pdc’s in the City of London constructed prior to this time will require repair or replacement due to the infiltration of tree roots through these unsealed joints. After the war, other types of pipe were utilized for pdc’s including: • Asbestos Cement (sometimes referred to as “transite pipe”) was very brittle, was not root proof due to the fact it required couplings to join the pipe sections and is not manufactured any longer due to the health issues associated with asbestos. • Bituminous Fibre Pipe (sometimes known as “no-corrode” pipe) w
