Soil Stack! Bendy or not ?

[marmaliser]

Hi all

In the process of designing a new shower / toilet room upstairs (current bathroom downstairs). I was wondering if soil stacks have to be vertical or whether there can be a kink in it like so

... |
... | - Toilet here
... |
.... \
..... \
...... \
...... |
...... |
...... | - Ground level
The kink would be required to avoid boiler flue and move the base so that an access chamber could be place without moving an existing underground gas supply pipe.

Thanks in advance for you help

 

[masona]

How many bends and what angle are they? e.g 90 or 112.5 degree etc..

Also not sure what the safety regulation if any regarding the soil stack with the boiler flue.

 

[marmaliser]

Hi thanks for the reply

I will have to do some calcs when I get home to work out the exact measurements and get back to the board.

As for Plastic pipes and boiler flue that could be an issue. Perhaps some foil heat reflective tape / sleeve where it is closest (Approx 150mm away) ?

 

[marmaliser]

Just looking at the range of Soil pipe I am using (Floplast) from screwfix
http://www.screwfix.com/app/sfd/cat/cat.jsp?cId=101624&ts=22881
They only do 92.5 and 135 bends. I assume 135's would be better. One to start the "kink" and one to return it (kinda like the original drawing above)

 

[breezer]

sorry you missed this one it is adjustable 0 - 90 degrees

 

[marmaliser]

 

[sifu]

Any combustible materials must be at least 25mm from an open flue pipe. For room-sealed or fan flued appliances horizontal clearances to a soil or drain pipe vary. If you have the installation instructions for your boiler it will say in there.