advice - adding/modifying soil pipes in bungalow

[grahaml]

Hi - first post here. I came across the forum while looking for advice and it seems to useful - I hope you may be able to offer me some advice?

I'm a pretty capable DIYer. I've installed 4 kitchens and 3 bathrooms in previous houses and upgraded our first house's central heating. All using copper pipes (although I think I am tempted to go plastic with the work in this house - but that will be another post no doubt!)

We moved into this modern-ish (1989 I think) bungalow in Scotland last winter. We plan to make a few changes and are part way through some of them (non plumbing related).

We wanted to add an en-suit to one of the bedrooms and also a cloakroom accessed from the back door off the utility room. On the face of it it should be relatively simple - the bathroom is at that end of the house too they will be all next door to each other - the main drain runs under the wooden floor in the solum.

I have been under the floor in these areas now - to see what is needed.

Now please excuse my ignorance or incorrect terminology - but hopefully you will understand enough to be able to advise?

It seems that most soil pipes run into a vertical stack but mine are horizontal (on a fall though). In the current bathroom the waste from the WC, shower, WHB and bath all go into a 110 soil pipe - which has a vertical vent running up through the roof. It then continues on a horizontal fall to a 90 degree bend and out the house to the main drain I assume.

It looks like they are push fit (Marley) fittings.

I appreciate it's maybe difficult to understand from my explanation - here's a sketch and a couple of photos


What is my best option for adding to this?
I was thinking that if I could replace the 90 degree bend as the pipe exits the house with a fitting that keeps the original pipe going to the left and allows me to add another to the right (for the ensuite).

Sorry if this is either a bit confusing - or maybe dead simple but advice appreciated. Try to keep it simple so I can understand!!

Many thanks
Graham

 

[Scott_1979]

I don't see an issue, easier would be just cut the pipe and add another tee before the 90 degree bend.

 

[Unregistered]

Thanks for the reply.

The 90 degree bend actually goes into the wall where it joins the rest of the pipe heading out the house.


As it is a push fit (I think) I should just be able to pull it off (is that right?). Could I add a tee there then re-attach the elbow?

That would push the pipe further from the wall - will that be ok and could it just be pointed back in the direction of the existing pipework?

is this the type of thing I would use as a tee?
92.5° (87.5°) Branch Grey SP190 | Soil Pipe Fittings | NoLinkingToThis

Thanks again

 

[grahaml]

sorry - that was me. My PC had logged me out and I hadn't realised

This is the pipe as it exits the house



Graham

 

[Scott_1979]

Yes it will be push fit, you can pull it apart. When putting it back in use some lubricating spray to put them together easier. That tee is close but you want all ends to be female, like the one on your second photo. Also when you cut the tee in as you say the pipe will then overshoot. Just simply cut some more out of the section that will have the elbow on it to make it fit properly. Also make sure to shampfer the ends of the waste pipe with a file.

 

[snowhead]

If the waste pipe is in a straight line you'll need a double branch and cap the centre with an access plug, so you get a sweeping bend from both directions.

110mm 92.5? Soil Pipe Double Branch (cross) Triple Socket

I don't think you'll get one with all sockets on so you'll have to use a straight connector (double socket) on the outgoing side.

Looks like you need some pipe clips on the existing as well.



.

 

[grahaml]

Thanks again- helpful practical advice - just what I was after.

The elbow currently coming out the wall is a male/female, not two female though.
Not sure if this is exactly what you meant - but does this sound feasible?

I will have;

1. the branch coming out the wall;
2. I will join the existing pipe into the branch - that will keep it as close as possible to the existing distance from the wall. Did you mean I can reduce the "length" of the branch by cutting a section off the end to fit?
3. I will join the elbow to the branch - heading in the opposite direction for my ensuite I plan

What's the best way to get the last pipe from the elbow to come back towards the wall where the WC will be? Would I just use a couple of elbows to bring it back to the wall?

like this...




many thanks again

 

[grahaml]

Snowhead - thanks also. That's what I was thinking initially in terms of the double branch - but I didn't see many and the one I did was surprisingly expensive. I also wondered about the 92.5 deg bit - is that angle OK? Ideally I want 90 or a little bit more (towards the wall).

I was thinking the same about supports for the existing pipes while I am at it!!

Thanks

 

[grahaml]

sorry duplicate post !!

 

[snowhead]

92.5 is O.K

If you use the double branch (Cross) you won't need to get it back to the wall.

Cheaper, ; https://shop.twsplastics.co.uk/110mm-90-degree-t-s-cross-tee.html

plus £7.96 postage

 

[grahaml]

Thanks, while I am here - a couple of related questions;

1. what would be the best way to connect the waste from the shower and whb? The existing bathroom ones go into 110mm branches with an adapter - is that OK or are there neater options?

2. Would I need a vent for the soil pipe in the ensuite - I'm thinking I would and would just do the same as in the existing bathroom - but into the loft space with an air admittance valve. Would that need to be 110mm or could I use smaller?

Thanks,
Graham

 

[Radioman]

The addition of a new bathroom and the modification of sewage disposal are notifiable to building control for certification or need to be carried out by a person registered as competent.

 

[brum]

Hi there I think the most difficult thing here may be getting your length of pipe down under the floor you may have to take it down in sections....brum

 

[grahaml]

Many thanks.
I hadn't thought about the issue of getting a length of pip under the floor. However access isn't too bad and the length I need isn't that long anyway - maybe less than 1m and the depth to the ground under the floor is about 600mm.

I'm checking the Building Control issue again with architect but I was advised at the outset from him that all was ok. I'm in Scotland and I know the regs are different from England. We will soon see though.

Any advice on earlier questions ?

1. what would be the best way to connect the waste from the shower and whb? The existing bathroom ones go into 110mm branches with an adapter - is that OK or are there neater options?

2. Would I need a vent for the soil pipe in the ensuite - I'm thinking I would and would just do the same as in the existing bathroom - but into the loft space with an air admittance valve. Would that need to be 110mm or could I use smaller?

Thanks for all the help.

Graham

 

[brum]

Hi again I got your thread mixed up with another one where the wc was a distance away if your only talking a couple of metres existing stack will suffice but a durgo wouldn't hurt to fit one plastic boss caps with reducing adaptors are best for shower and basin also durgo could go down to two inch pipework ....brum