changing cast for plastic ??

[bigdek]

my dad wants to fit an on suite in his bedroom.

curently it has a sink but he is going to build a seperate room for the on suite.

The sink currently drains into a cast pipe on the outside wall it is only about 2 1/2 to 3 " in diamer.

Is it ok to dig this out of the ground and replace fully with 110 mm plastic ??

 

[ChrisR]

For a basin, sink or shower; probably, check with your local building control office.
For a wc, NO, has to be 110 all the way to wherever it goes underground

 

[bigdek]

about a foot away from where the pipe goes into the ground there is a small square cover plate.

Looking inside it it kooks like it is 4" clay

 

[kevplumb]

if its 4"" clay no problem

 

[jas05]

your "small square cover plate" is most likely to be
a fireclay "trap".

dig down and then discard the trap by cutting the pipe just beyond
it with a stihl saw ( assuming there are no other pipes using it )

use a flexicon rubber adaptor to connect the fireclay to 110mm
underground drain

use a long radius bend at the wall.

 

[bigdek]

The house is a 3 storeys so was going to fit a Durgo valve instead of

taking the stack above the roof .( also don't have a triple ext ladder )

What height above the T branch for the WC waste should the valve be



fitted ??

 

[kevplumb]

of the top of my head 300 above the highest flood level (handbasin)