Soil stack advice? (external)

[robodelfy]

Hi, I'm looking to re do all the waste pipes on the back of my house as I'm fitting new toilets etc. I've never done this before, so just wanted to make sure I'm on the right track. If you see the current photo

I plan to basically replicate this, but go more directly to the toilet waste, without those double 45 degree bends they've used.

Do I need an access fitting for rodding near the very bottom where the straight couple currently is?

The plumber told me to have lower pipes slotting into high pipes to avoid anything getting in, but as far as I can tell the t junctions and straight couples don't allow for this. Does it really matter?

Also I have a 21.5mm overflow pipe from the boiler upstairs, just dropping into a 36mm pipe, not sealed. Can you get an adaptor for this

Any other glaring issues you can see?

 

[Hugh Jaleak]

Does the stack run directly to a manhole? If so, no need for a access point on the stack, (always takes a brave person to open it if there's a problem anyway, rarely the stack blocks, problem is usually underground but has backed up the stack...)

Not sure what you mean by lower pipes slotting into high pipes? If you're talking about having the sockets pointing downwards, then no, absolutely no benefit in doing that, and a very strange theory from your 'Plumber'. If the joints are made correctly then nothing will get in (or out!) anyway.

Condensate drain, yes you can get a 21.5mm adaptor to the waste pipe, ideally I'd be looking to run that initial section internally, and join onto the shower waste inside the building. It is rather a long run to have exposed, bear in mind if it freezes up you will have major problems.

Swan neck at the top, use correct bends which glue together, and stops it twisting about in the wind.

 

[robodelfy]

Does the stack run directly to a manhole? If so, no need for a access point on the stack, (always takes a brave person to open it if there's a problem anyway, rarely the stack blocks, problem is usually underground but has backed up the stack...)

Not sure what you mean by lower pipes slotting into high pipes? If you're talking about having the sockets pointing downwards, then no, absolutely no benefit in doing that, and a very strange theory from your 'Plumber'. If the joints are made correctly then nothing will get in (or out!) anyway.

Condensate drain, yes you can get a 21.5mm adaptor to the waste pipe, ideally I'd be looking to run that initial section internally, and join onto the shower waste inside the building. It is rather a long run to have exposed, bear in mind if it freezes up you will have major problems.

Swan neck at the top, use correct bends which glue together, and stops it twisting about in the wind.

Thanks, I have no idea what it runs in to. Should I just dig up around it to start with and find out?

Yes he said sockets pointing downwards. I thought that was a bit weird, as its only rain and the push fit fittings are so tight and sealed.

Sorry what does swan neck the top mean? Like two 45 degree bends to get around the gutters and then pointing up at the top?

The 21.5mm pipe actually only comes out of the house a few inches, and drops into the top of the other waste pipe, I dont think much water comes out of it, so I'm not sure this would still be a risk of freezing

 

[Hugh Jaleak]

Lift manhole cover, get someone to flush the WC, see where/if it comes out. If unsure, then for what it's worth, fit a rodding access in the stack, it's not going to hurt anything.

Sockets downwards, weird. It doesn't matter having a joint on the underside, if using a coupling or something, but junctions are swept, so must be used in the correct orientation, (perhaps your Plumber is responsible for all the soil ski jumps we keep seeing?)

Swan neck, yes at the top to clear the gutters. Use a bottom and top offset 45° bend, you glue these to form the swan neck so they cant twist and move out of place.

Condensate drain, boiler can produce up to a litre an hour when working hard, the pipework can and does freeze, condensate backs up and then the boiler switches off as it goes into fault mode. Even if frost protection is fitted to the boiler, it still wont operate due to being unable to discharge the condensate, and then runs the risk of the boiler and/or pipework in the building, also freezing. It is vital condensate runs are protected from cold conditions as much as possible.

 

[robodelfy]

Lift manhole cover, get someone to flush the WC, see where/if it comes out. If unsure, then for what it's worth, fit a rodding access in the stack, it's not going to hurt anything.

Sockets downwards, weird. It doesn't matter having a joint on the underside, if using a coupling or something, but junctions are swept, so must be used in the correct orientation, (perhaps your Plumber is responsible for all the soil ski jumps we keep seeing?)

Swan neck, yes at the top to clear the gutters. Use a bottom and top offset 45° bend, you glue these to form the swan neck so they cant twist and move out of place.

Condensate drain, boiler can produce up to a litre an hour when working hard, the pipework can and does freeze, condensate backs up and then the boiler switches off as it goes into fault mode. Even if frost protection is fitted to the boiler, it still wont operate due to being unable to discharge the condensate, and then runs the risk of the boiler and/or pipework in the building, also freezing. It is vital condensate runs are protected from cold conditions as much as possible.

I will have to dig up all the earth around where it goes in the ground to see whats down there.

As for the condensate drain, I dont know what to do. I cant see an easy way to run this inside. The thing is, the actual 21.5mm pipe only comes out of the house a few inches as I said, then goes into the main waste pipes. It's going to be incredibly hard to get it to join the bath waste internally I think

 

[robodelfy]

Lift manhole cover, get someone to flush the WC, see where/if it comes out. If unsure, then for what it's worth, fit a rodding access in the stack, it's not going to hurt anything.

Sockets downwards, weird. It doesn't matter having a joint on the underside, if using a coupling or something, but junctions are swept, so must be used in the correct orientation, (perhaps your Plumber is responsible for all the soil ski jumps we keep seeing?)

Swan neck, yes at the top to clear the gutters. Use a bottom and top offset 45° bend, you glue these to form the swan neck so they cant twist and move out of place.

Condensate drain, boiler can produce up to a litre an hour when working hard, the pipework can and does freeze, condensate backs up and then the boiler switches off as it goes into fault mode. Even if frost protection is fitted to the boiler, it still wont operate due to being unable to discharge the condensate, and then runs the risk of the boiler and/or pipework in the building, also freezing. It is vital condensate runs are protected from cold conditions as much as possible.

I've had another look today, and it's possible I could cut a section out a floorboard to get to the bath waste, but how do you attach 21.5mm pipe into the side of 40mm pipe, in a tight space?

 

[Hugh Jaleak]

I've had another look today, and it's possible I could cut a section out a floorboard to get to the bath waste, but how do you attach 21.5mm pipe into the side of 40mm pipe, in a tight space?

You'll need to graft a Tee into the waste then fit a 21.5 to 40mm reducer in the tee, then connect the condensate. Having said that, I'm not sure though if you should be altering the condensate drain, it technically forms part of the flue way for the boiler, and should be done by a Gas Safe engineer.

 

[robodelfy]

You'll need to graft a Tee into the waste then fit a 21.5 to 40mm reducer in the tee, then connect the condensate. Having said that, I'm not sure though if you should be altering the condensate drain, it technically forms part of the flue way for the boiler, and should be done by a Gas Safe engineer.

Yes I decided on doing exactly what you mentioned, but I didn't realise it should be done by a gas safe engineer. I will have to find that out, seems a bit over the top if it does. I am essentially doing what I'd be doing on the outside of the house, but on the inside