Toilet/rainwater into soil stack

Swasterix

Afternoon All,

We are wanting to reposition out toilet in our upstairs bathroom onto the adjacent wall. Currently the guttering runs down the back of the house into the drain below. I was wondering whether it is doable to replace the down pipe and have both rainwater and toilet waste running into the same down pipe? Drains are combined, so guess that’s not an issue. Rainwater currently runs into the sewer, not a soak away. 

If there are no obvious issues, am curious to know whether this is DIYable, if so, what exactly would be required? If not, a rough cost to get somebody in? 

Below images may give you a better idea. Red is the position of the current toilet waste, green is roughly where we would like it to be. 

Cheers in advance!

Blackbeard_of_Perranporth

It appears that your toilet at the moment discharges into a Soil Stack, that vents your sewer. Moving this I assume you would also have to move the Soil Sack at the same time.

Swasterix

Blackbeard_of_Perranporth said:

It appears that your toilet at the moment discharges into a Soil Stack, that vents your sewer. Moving this I assume you would also have to move the Soil Sack at the same time.

Yes- I understand that the down pipe would need replacing. 

Both the soil stack and gutter pipe discharge into the same sewer, they just take different routes. 

Was more wondering whether there was anything logistical/regulatory that would prevent me from doing it. If not, rough cost/scheme of work to do it. 

Carrot007

A new downpipe would be notifiable work I believe.

Cutting the hole though the wall for toilet waste is a right pain.

Anything else use the downpipe? What are your plans for the old one? Hopefully not building over unless diverting all the pipes.

All I can think of.

Swasterix

Carrot007 said:

A new downpipe would be notifiable work I believe.

Ok, will look into this thanks

Cutting the hole though the wall for toilet waste is a right pain.

I recently had to cut one for an extractor fan outlet, was not fun 😂

Anything else use the downpipe? What are your plans for the old one? Hopefully not building over unless diverting all the pipes.

There is also a toilet downstairs which tees into the existing soil stack. My plan was to remove the branch for the upstairs toilet, add a coupler (assuming they exist) and vent to above the roof (as it is now).

All I can think of.

Answers above, thanks for the reply. 

Doozergirl

You can use the existing soil pipe from there.  Whether you choose to run it internally or externally is up to you, but externally isn't going to have a hugely detrimental effect on the aesthetic of the house. 

I'd run it sideways from the loo, boxed in with a concealed cistern, and have it pop out of the side of the house, straight to the existing soil stack.  

Cheaper and better looking.  

Job done.  

Swasterix

Doozergirl said:

You can use the existing soil pipe from there.  Whether you choose to run it internally or externally is up to you, but externally isn't going to have a hugely detrimental effect on the aesthetic of the house. 

I'd run it sideways from the loo, boxed in with a concealed cistern, and have it pop out of the side of the house, straight to the existing soil stack.  

Cheaper and better looking.  

Job done.  

Thanks for the reply Doozer! Sounds promising.

Yes- the rear of the house isn’t aesthetically pleasing in the slightest, so agree would make little difference 😂 We do have future plans to improve it (another thread entirely)! The garden is beautiful and the view of the house really lets it down!!

The existing down pipe is roughly 65mm square profile, so presume this would need to be changed for a 110mm soil pipe? Could you hazard a guess as to how much of a job it would be to swap? I can’t really envisage how the connection is made to the sewer below ground. 

Thanks again

daivid

If you do as Doozergirl suggests (which I would) you wont need to replace the down pipe as you will be running the toilet waste into the existing soil stack. Cost will be minimal: an elbow joint or two and a piece of 110mm soil pipe (which can be the cheaper brown pipe as it won't be exposed to light). The main thing to check is you can maintain a good gradient from the new toilet location to the point you join the existing stack. 1 in 40 is the ideal IIRC though it doesn't have to be exactly that.

Swasterix

daivid said:

If you do as Doozergirl suggests (which I would) you wont need to replace the down pipe as you will be running the toilet waste into the existing soil stack. Cost will be minimal: an elbow joint or two and a piece of 110mm soil pipe (which can be the cheaper brown pipe as it won't be exposed to light). The main thing to check is you can maintain a good gradient from the new toilet location to the point you join the existing stack. 1 in 40 is the ideal IIRC though it doesn't have to be exactly that.

Aah, I’ve fully misunderstood what Doozer was saying in that case! Apologies!

I don’t think that would be a possibility unfortunately. I intend to put a shower cubicle in the place where the toilet is currently, so wouldn’t be possible to run it that way I don’t think. Also, the back of the toilet would be on the back wall of the house where the gutter down pipe runs. Hope that makes sense!

Carrot007

Swasterix said:

daivid said:

If you do as Doozergirl suggests (which I would) you wont need to replace the down pipe as you will be running the toilet waste into the existing soil stack. Cost will be minimal: an elbow joint or two and a piece of 110mm soil pipe (which can be the cheaper brown pipe as it won't be exposed to light). The main thing to check is you can maintain a good gradient from the new toilet location to the point you join the existing stack. 1 in 40 is the ideal IIRC though it doesn't have to be exactly that.

Aah, I’ve fully misunderstood what Doozer was saying in that case! Apologies!

I don’t think that would be a possibility unfortunately. I intend to put a shower cubicle in the place where the toilet is currently, so wouldn’t be possible to run it that way I don’t think. Also, the back of the toilet would be on the back wall of the house where the gutter down pipe runs. Hope that makes sense!

Could still do it outside if the drop was enough as said. Though I would not. DIY the new stack costs hardly anything. It's all cheap plastic pipe. A stack in the right place would look better. It's basically change the bottom drain to a closed one. (if that leafy bit is actually part of the drain with an open cover?). Digging up the concrete is a pain. But it's not much, saw to cut lines and pick option on sds.

However is is effort! But if you are prepared then it is easy. I replaced around 3 metres of collapsed sewer at my old house. Had to kill a wet vac doing it. as icky backed up! (Had to get next door to do their part as well but was council). Also reaplced the water main incoming from lead which was 15 metres and a bit of digging a hole! That's where the cost comes in for such jobs. The labour!

Swasterix said:

Carrot007 said:

Cutting the hole though the wall for toilet waste is a right pain.

I recently had to cut one for an extractor fan outlet, was not fun 😂

Should be ok then! I once did one usinf nothing more than a 15 mm drill bit meant to make a hole for a copper pipe (ok so 16mm I would guess more than 15!). Many holes, big circle. Did the job. Better tools were unfortunatly not taken to the house that day!

flashg67

Carrot007 said:

Cutting the hole though the wall for toilet waste is a right pain.

I recently had to cut one for an extractor fan outlet, was not fun 😂

Should be ok then! I once did one usinf nothing more than a 15 mm drill bit meant to make a hole for a copper pipe (ok so 16mm I would guess more than 15!). Many holes, big circle. Did the job. Better tools were unfortunatly not taken to the house that day!

Cost me less than £25 to rent a diamond hole saw, drill & transformer to do mine - took me about an hour (my first time having a go at a job like this!) but was pleased at how neat the job was. I used push fit soil pipe & fittings and a 'durgo' valve to avoid having to take the stack above the roof line.