Hello. This is my first ever post asking for help. I had a bathroom renovation done early this year which I did myself. I wanted to have a low level shower tray sitting flush to the ground and was not able to get access to the main vented stack as it's boxed in from the inside of the house and from the outside it's pretty much impossible because the flat roof level is higher than the floor level in the bathroom. So what I ended up doing is running a 40mm vertical waste pipe and using a 40mm sweeping tee I tapped into the downstairs shower which is also on a 40mm plastic pipe running horizontally along at floor level. The 40mm Tee was added near the end of the waste run to ensure that there is no back washing of the water into the ground floor shower. It has not caused any issues so far. This pipe discharges into the main sewer line but it's not via the vented stack. The WC also discharged its waste via a different waste route. I have opened up the manhole and can see that the upstairs stack route and downstairs waste route is completely different. I've never had an issue with any of my plumbing before with blockages and I think that may be down to the fact that the plumbing infrastructure below ground is quite good. Now that I've started to modernise my home I think to bring everything up to standard I should add an internal AAV but I'm sure on how or where, and this is where I would appreciate some advice. Now that I've rested up I'm now thinking of starting downstairs in a couple of months.
The first floor WC and sink all get discharged into the vented soil stack.
1. Adding an AAV to the shared 40mm shower waste line.
2. Running a new waste for a sink downstairs and the only way to do this would be either tapping into the shower waste again - not preferred or to plumb into the WC using a pan connector with a 32mm or 40mm vent boss.
3. If I were to plumb into the WC pan, would this cause any siphoning, when the WC is flushed? If so what could I add to the line to ensure that this does not happen.
4. Can one AAV installed into a shared pipework work for everything connected to it?
5. I may upgrade the horizontal pipe to a 50mm waste for the downstairs shower but that will only run far as where the 40mm sweeping tee connects. it's about a 4m run. would this make any difference?
6. The distance from where the 40mm sweeping tee connects to the main soil point is only 30cm.
Apologies in ADV for any silliness, I'm just a guy who's wanting to save money by doing the work myself and do it with heart without cutting corners and do a damn good job. I appreciate any advice given.
The first floor WC and sink all get discharged into the vented soil stack.
1. Adding an AAV to the shared 40mm shower waste line.
2. Running a new waste for a sink downstairs and the only way to do this would be either tapping into the shower waste again - not preferred or to plumb into the WC using a pan connector with a 32mm or 40mm vent boss.
3. If I were to plumb into the WC pan, would this cause any siphoning, when the WC is flushed? If so what could I add to the line to ensure that this does not happen.
4. Can one AAV installed into a shared pipework work for everything connected to it?
5. I may upgrade the horizontal pipe to a 50mm waste for the downstairs shower but that will only run far as where the 40mm sweeping tee connects. it's about a 4m run. would this make any difference?
6. The distance from where the 40mm sweeping tee connects to the main soil point is only 30cm.
Apologies in ADV for any silliness, I'm just a guy who's wanting to save money by doing the work myself and do it with heart without cutting corners and do a damn good job. I appreciate any advice given.
