Does the main soil stack have to be completely vertical?

[me]

I can't seem to find any examples of a soil stack that doesn't have a main, completely vertical part, into which all the toilets join via branches. No w is this because there are bulding regs specifying this or it it just not common practice to have a "bent" vertical soil stack?

What I want to do is go out from the loo to a T branch as the first joint o n the outside, so there'll be a vertical up and vertical down joint availab le. The vertically up joint of the T will go vertically over the roof line with a swan neck. The vertically down joint immediately joins to a 92.5 ben d which then goes via an almost horizontal pipe to another 92.5 bend which then continues vertically to the ground. Access panels on the T branch and the second 92.5 bend.

Any problems (bulding regs wise)with that setup?

[me]

Thanks Phil, but does it also comply with buildinbg regs? As you know, what works in practice and what the building surveyor will allow can be two different things!

[Max Demian]

Why do all soil stacks in a row of houses have a vent at the top? Surely they all connect to the same sewer? Shouldn't venting the sewer be the responsibility of the water board (or whoever installs it)?

[Andrew]

Err, without the soil stack vent, when you flushed your toilet, or even when an upstream neighbour flushed their toilet the vacuum could suck out your WC water trap allowed nasty niffs into your house.

Building regs allows for at most, every 3rd house to have an internal Durco valve instead of a vented stack. It does the same thing, by allowing air into the stack when there is a pressure differential, but doesn't work in reverse.

[Bob Minchin]

I have a horizontal (2.5 degree fall) run from a loo about 2.5 m long. It was passed by BCO in 1985 without query. There is a rodding point where it joins the stack

We are in a hardwater area and over about 30 years the bottom of the pipe run surface has become covered in a shit coloured chalky hard deposit which increases the friction to flow and it can block a bit after "heavy" use. A possible solution is to rotate the pipe with a strap wrench through about 60-90 degrees to give a new smooth surface. If yet to try this just in case the push fit seals then object leading to a worse problem!

[The Natural Philosopher]

Brick acid. Or get yourself a water softener

Brick or patio acid is reasonably conc. hydrochloric and the 'cement' will fizz and give off stinky CO2 but will dissolve quite fast. it needs a puddle upstream to stay there and eat away at it. Too much will be wasted. A cupful in the loo every flush for a week or two

[Tricky Dicky]

You get some weird arrangements in Victorian properties especially where th e original building has been sub-divided. My daughters and SIL's first prop erty was a an upstairs flat above what originally was quite a large Victori an shop with upstairs store rooms. The property was sub-divided into smalle r units of mixed commercial and residential. In the lounge area of the flat was a low shelf boxed in below with a platform in one corner for a TV. Thi s shelf went the full length of the window wall and partially along a divid ing wall to next door. It turned out that this "shelf" and boxing in contai ned the soil pipe from next door running approx. 8m horizontally through th eir property before exiting outside to drop down to the sewer. Their own wa ste pipe did not join this as their bathroom was in a rear extension and th e soil pipe went vertically down through the commercial property below. I a lways wondered who would have to foot the bill if ever there was a leak on the part passing through their lounge?

Richard

[Andrew]

My grandparents house in Epsom had a lead stack outside the house, going right down into the ground and a lead connection into the toilet on the 1st floor. A builder bought the house in 1993 when she died and I suspect the value of the scrap lead more than covered the cost of a new plastic stack.

Don't think a cup of acid every week would have been a good idea.

[The Natural Philosopher]

would be if its covered in lime

Very little lead sewage systems.

Been clay subsurface/cast iron above since first installed. Latterly PVC.