The market price of vitrified clay pipes is generally less than that of precast concrete pipes with PVC lining.
Therefore, for small size of pipes (pipe diameter less than 600mm) it is more economical to use vitrified clay pipes.
However, vitrified clay pipes do suffer from the problem of brittleness and its effect is even severe for larger size of pipes.
Moreover, it is rather time consuming to deliver clay pipes products because the majority of them are manufactured in Europe.
Hence, for larger size of sewer pipes (diameter more than 600mm) it is customary to use precast concrete pipes with PVC lining.