Pocster Posted October 16, 2019 Share Posted October 16, 2019 Every house i’ve Lived in had one of these ; not particularly pretty . On large building sites I don’t see any . I assume it’s a requirement so how do they do a ‘hidden’ stench pipe ??? Link to comment Share on other sites More sharing options...
NSS Posted October 16, 2019 Share Posted October 16, 2019 10 minutes ago, pocster said: Every house i’ve Lived in had one of these ; not particularly pretty . On large building sites I don’t see any . I assume it’s a requirement so how do they do a ‘hidden’ stench pipe ??? Our stink pipes run up into the roof space and then exhausts via a tile vent. Seems to be standard practice these days. 1 Link to comment Share on other sites More sharing options...
Pocster Posted October 16, 2019 Author Share Posted October 16, 2019 1 minute ago, NSS said: Our stink pipes run up into the roof space and then exhausts via a tile vent. Seems to be standard practice these days. Ah right ! That’s why I don’t see great dirty pipes everywhere. So does the vent have to be as ‘high’ as possible up the roof ? . I guess i’m Asking what’s the min height from presumably the ‘nearest’ toilet ??? Link to comment Share on other sites More sharing options...
Carrerahill Posted October 16, 2019 Share Posted October 16, 2019 16 minutes ago, pocster said: Every house i’ve Lived in had one of these ; not particularly pretty . On large building sites I don’t see any . I assume it’s a requirement so how do they do a ‘hidden’ stench pipe ??? They are all internal now - usually a boxed in pipe runs through the kitchen. They have a vent at roof level. 1 Link to comment Share on other sites More sharing options...
Pocster Posted October 16, 2019 Author Share Posted October 16, 2019 Do they have to run vertical? Can they twist and turn to get to the roof vent ? Link to comment Share on other sites More sharing options...
Carrerahill Posted October 16, 2019 Share Posted October 16, 2019 1 minute ago, pocster said: Ah right ! That’s why I don’t see great dirty pipes everywhere. So does the vent have to be as ‘high’ as possible up the roof ? . I guess i’m Asking what’s the min height from presumably the ‘nearest’ toilet ??? The spec is x mm away from an opening, window or vent. Link to comment Share on other sites More sharing options...
NSS Posted October 16, 2019 Share Posted October 16, 2019 Just now, pocster said: Do they have to run vertical? Can they twist and turn to get to the roof vent ? Ours run vertically into the roof space and then at a variety of angles. We even have a short section that runs horizontally. 1 Link to comment Share on other sites More sharing options...
Carrerahill Posted October 16, 2019 Share Posted October 16, 2019 Just now, pocster said: Do they have to run vertical? Can they twist and turn to get to the roof vent ? Our new soil stack goes up to roof level of the single storey section of the house, then takes a 90° at the last branch (where a pan connects) then goes about 400mm horizontal (or 92.5°) then through a wall, then 90° and up the side of the house. So I am going to say yes. Link to comment Share on other sites More sharing options...
Jeremy Harris Posted October 16, 2019 Share Posted October 16, 2019 If you can get away without having one internally then it is worth doing, as they are always a thermal bridge, wasting a bit of heat. The key thing is to recognise that SVPs have two functions. One is to vent any gasses that may build up in the foul drain, the other is to allow air to enter above any slug of waste that goes down the pipe after a toilet is flushed. These two functions can be separated out, and doing this removes the thermal bridge. An external vent can be fitted to the foul drain, outside the house. This doesn't need to go to roof level, it's OK to have it above any flood level, in a location where any slight odour won't be noticed. Putting a vent near, or in, a hedge or some bushes will avoid any odour, as plants seem to be pretty good at neutralising smells. To resolve the requirement to allow air into the soil pipe after a toilet flush, you can fit a short internal pipe up above the highest drain point, and cap it with an air admittance valve. We've done this, and have no visible vent pipes at all. The AAV sits in the eaves space, where it can be accessed if needed. 3 1 Link to comment Share on other sites More sharing options...
joe90 Posted October 16, 2019 Share Posted October 16, 2019 2 minutes ago, pocster said: Do they have to run vertical? Can they twist and turn to get to the roof vent ? Yes as long as they are still rising (hence 92.5k bends) 2 minutes ago, Carrerahill said: The spec is x mm away from an opening, window or vent. Not away but above, loft conversions should extend the soil pipe above the new loft windows. Link to comment Share on other sites More sharing options...
Temp Posted October 16, 2019 Share Posted October 16, 2019 Somewhere I've read that you only need one open vented stack for every four or five houses these days. Cant find that in the Approved Docs but google found a reference here.. "Building Construction Handbook" https://books.google.co.uk/books?id=7eAhNzZW1goC&pg=PA846&lpg=PA846&dq=one+open+vented+stack+ever+four+dwellings&source=bl&ots=tK13FKNupg&sig=ACfU3U1pU0TMwSQa0xcSaUFx9tnojD06AA&hl=en&sa=X&ved=2ahUKEwjUto7_0qDlAhXSbsAKHfjgD10Q6AEwDnoECAcQAQ#v=onepage&q=one open vented stack ever four dwellings&f=false AAV Application - upto four dwellings.... snip...the fith to be conventionally vented at the highest part of the drain serving all four dwellings 2 Link to comment Share on other sites More sharing options...
joe90 Posted October 16, 2019 Share Posted October 16, 2019 Like @JSHarris we have an aav (50mm) in the airing cupboard just below ceiling level upstairs and this is to avoid “gurgling” in any traps in the house. We also have a vent pipe on the detached garage to vent the treatment plant. 1 Link to comment Share on other sites More sharing options...
joe90 Posted October 16, 2019 Share Posted October 16, 2019 3 minutes ago, Temp said: Somewhere I've read that you only need one open vented stack for every four or five houses these days. Cant find that in the Approved Docs but google found a reference here.. Thats on houses with mains drains or sharing a treatment plant. 1 Link to comment Share on other sites More sharing options...
cwr Posted December 3, 2019 Share Posted December 3, 2019 So is there a max distance for an external vent to be away from the house/toilet? Link to comment Share on other sites More sharing options...
Pocster Posted January 15, 2020 Author Share Posted January 15, 2020 So if I do a roof vent what are the rules on this ? . Simply place it high as possible up the roof ???? Link to comment Share on other sites More sharing options...
joe90 Posted January 15, 2020 Share Posted January 15, 2020 On 03/12/2019 at 22:37, cwr said: So is there a max distance for an external vent to be away from the house/toilet? my vent pipe is on my detached garage 15m from the house (I do have an internal 50mm aav to stop any “gurgling” in traps). Link to comment Share on other sites More sharing options...
Thedreamer Posted January 15, 2020 Share Posted January 15, 2020 Outlet in roof are not a good idea if you have room in the roof design. Our one sticks out of the roof so it's vents a bit higher up. Link to comment Share on other sites More sharing options...
Nick1c Posted January 15, 2020 Share Posted January 15, 2020 I discussed this with BC this week. Our house is at the top of the foul run, next door has an SVP 20m away. He would accept an AAV in the loft, but would prefer an SVP as belt & braces. He wasn't too fussy about the route but wanted the pipe to be as big as possible (up to 110mm) where possible. The plumber suggested a vented slate which will have to penetrate a 400mm warmcell roof. 1 Link to comment Share on other sites More sharing options...
Pocster Posted January 16, 2020 Author Share Posted January 16, 2020 10 hours ago, Nick1c said: I discussed this with BC this week. Our house is at the top of the foul run, next door has an SVP 20m away. He would accept an AAV in the loft, but would prefer an SVP as belt & braces. He wasn't too fussy about the route but wanted the pipe to be as big as possible (up to 110mm) where possible. The plumber suggested a vented slate which will have to penetrate a 400mm warmcell roof. I assumed I need an AAV and stench pipe ? I.e both - this not correct ?? Link to comment Share on other sites More sharing options...
Mr Punter Posted January 16, 2020 Share Posted January 16, 2020 37 minutes ago, pocster said: I assumed I need an AAV and stench pipe ? I.e both - this not correct ?? If the neighbouring houses are connected to the same drain and they have vent pipes you could just have an AAV. If not, you will need to vent to atmosphere. If you have more than 1 soil pipe you will need either an AAV or vent to atmosphere at the top of each. 1 Link to comment Share on other sites More sharing options...
Pocster Posted January 16, 2020 Author Share Posted January 16, 2020 (edited) 53 minutes ago, Mr Punter said: If the neighbouring houses are connected to the same drain and they have vent pipes you could just have an AAV. If not, you will need to vent to atmosphere. If you have more than 1 soil pipe you will need either an AAV or vent to atmosphere at the top of each. Excellent! The house on the same drain ( which I use to own ) has a stench pipe . Their drain joins into my new build which in turn joins straight into the main drain . Just an AAV then ? Edited January 16, 2020 by pocster 1 Link to comment Share on other sites More sharing options...
Dreadnaught Posted January 16, 2020 Share Posted January 16, 2020 Yes, at my plot, I went around taking photos of the pipes-in-the-sky on all the neighbouring buildings. I am hoping to avoid an SVP on my build too, just AAVs. Fingers crossed that BC will agree. 1 Link to comment Share on other sites More sharing options...
Pocster Posted February 16, 2020 Author Share Posted February 16, 2020 (edited) Ok ! umm ‘d and ahh ‘d about this . Stench pipe will be internal - so a 4inch pipe off the main internal drain ok ? Can’t find any regs about where it’s vent should ( or shouldn’t ) go on the roof ! - assume not critical then .... Architect wants stench pipe and AAV Edited February 16, 2020 by pocster Link to comment Share on other sites More sharing options...
Pocster Posted February 16, 2020 Author Share Posted February 16, 2020 (edited) Ah confused myself again ! I’m sure the architect isn’t as clued up ... There’s lots of suggestion that you shouldn’t have an open stench pipe . Indeed you can even get an external AAV that sits on the stench pipe .. I don’t really want to penetrate the roof for a stench vent if it’s not necessary . Can I come off my WC internally ; take a pipe up into the loft and ‘joint’ it towards the loft hatch ; put an AAV ontop ? Makes access for the AAV easy , it’s higher than any cistern - but does it have to be a straight run ? i.e can the pipe work be horizontal for a bit ? Edited February 16, 2020 by pocster Link to comment Share on other sites More sharing options...
joth Posted February 16, 2020 Share Posted February 16, 2020 (edited) Ultimately you can do whatever your building inspector will sign off... However we have already experienced they'll approve one thing on paper then change their mind after you've installed it, so better safe than sorry. Our plans put AVV in the loft and an external open vent from the drain routed from the end of the main drain, up the outside of the house to the eves next to a drain pipe. My own simplified interpretation is that the regs require all horizontal drains to have a free flow of air through them, but this doesn't necessarily have to be through a stack pipe used internally in the house (or otherwise). Edited February 16, 2020 by joth 1 1 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now