How many vents on drain pipes?

Hello experts,

Here's the situation: new build dormer bungalow, five toilets (yes, five - two are for a childcare facility), a black drain pipe at each gable, one of which has a vent, the other curves directly into the wall.

Snagger has said that both should be vented, builder says they're both on the same mains and one is sufficient. Any guidance/advice/opinions?

Thanks!

Hi,

The snagger is not correct. In your case you have a bungalow.....You only need a vent stack on your pipe where then drop is more than 1.5m see page 6 of Technical documents for Building Regulations. These can be viewed on http://www.environ.ie (www.environ.ie) (government website) . I live in Co Westmeath and had similar problems with drainage. Westmeath Co Co were very helpful. See Building Control on www.westmeathcoco.ie . Check out your own local building control authority for information

rexo

Hi Rexo, thanks for the feedback,

It's actually a dormer bungalow, i.e. a storey-and-a-half; the drain in question curls into the wall upstairs, going into a master bedroom en suite. (Sorry, should have made this more clear in the initial post)

So the drop would indeed by more than 1.5m... in your experience, would this mandate a separate vent for this pipe, then?

Also, according to TGD H, para 1.3.4, there's a suggestion that a line more than 6m from the main stack needs its own vent - this drain is about 12m away, at a guess. (I may be misunderstanding the TGD text here, though).

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Also, according to TGD H, para 1.3.4, there's a suggestion that a line more than 6m from the main stack needs its own vent - this drain is about 12m away, at a guess. (I may be misunderstanding the TGD text here, though).[/quote]

Hi again,
You have quoted a detail from the section Foul water drainage - pipework underground. Your problem relates to Foul water drainage pipework overground. Anyway you and snagger boy are right, you should have all discaharge pipes vented if they are falling that height. To flex a bit of muscle for the builder, ask the building control section to send you a letter confirming that this is required.

"The Technical guidance documents are only guidelines"( this is usually spouted by builders under pressure) however where the builder does not build in accordance with the guidelines then he has a legal obigation to prove that what he has done is equivalent. If you wave a letter from the bca in council in his face he might just go ahead and do it. Otherwise ask the building control authority to serve him with an enforcement notice. Its their duty to investigate complaints and make sure building regulations are complied with.If they dont send them a letter of complaint i.e to county manager.

its all a bit heavy handed but sometimes thats what it takes

Thanks again Rexo, that's very interesting stuff. I don't anticipate a huge difficulty getting the builder to fix it but glad to have your advice on involving building control in case of emergency!

Much appreciated.

Hi Yorky,

Your situation sounds exactly the same as mine (although ours are side-to-side, rather than your front-to-back) so I guess the same advice given above applies.

(Re the implications, I don't know - but I'm guessing there could be issues with smells, access to clear blockage, maybe a greater possibility of both occurring... also, potential legal issues if building regs aren't satisfied. But I could be wrong)