External AAV

[buffster]

I'm having to extend a SVP to accommodate a new upstairs bathroom. The SVP currently vents upwards at the end of the original extension of my Victorian terrace. I want to put a bathroom on the first floor by branching the existing SVP, allowing it to vent as it does now but extending the branch back to the main part of the house and running it up the rear wall. Then I'm a bit stuck. I can't really have the extended bit as an open SVP as there are attic windows within 3m of wherever it could run, and exteending it above them is impractical. The new bathroom isn't very big, and I wouldn't want to have to squeeze pipework for an AAV in there. I was considering extending the soil pipe, taking it into the house just below the eaves, and fitting an AAV in the eave space at the edge of the attic bedroom. Then I saw this (hopefully I'll be allowed to post a link)

FloPlast AX110 External Air Admittance Valve

I've been told that because it is BBA approved it should be OK, but I just wondered if anyone has installed one? Anyone tried to get one approved by BC yet?

 

[fuzzy]

I'm having to extend a SVP to accommodate a new upstairs bathroom. The SVP currently vents upwards at the end of the original extension of my Victorian terrace. I want to put a bathroom on the first floor by branching the existing SVP, allowing it to vent as it does now but extending the branch back to the main part of the house and running it up the rear wall. Then I'm a bit stuck. I can't really have the extended bit as an open SVP as there are attic windows within 3m of wherever it could run, and exteending it above them is impractical. The new bathroom isn't very big, and I wouldn't want to have to squeeze pipework for an AAV in there. I was considering extending the soil pipe, taking it into the house just below the eaves, and fitting an AAV in the eave space at the edge of the attic bedroom. Then I saw this (hopefully I'll be allowed to post a link)

FloPlast AX110 External Air Admittance Valve

I've been told that because it is BBA approved it should be OK, but I just wondered if anyone has installed one? Anyone tried to get one approved by BC yet?

just help me a little - is this the only vent or a second vent? wil the aav be external?

 

[buffster]

just help me a little - is this the only vent or a second vent? wil the aav be external?

The pipe rises vertically from the existing ground floor toilet and vents there, at a height of approximately 4m. I want to branch it about 2.3m up, leaving the original vent in place but creating a substack (?) approximately 3.3m away to service the new bathroom, and it is on the top of this that I'm looking to use the AAV which will be external.

So, this would be a second vent, and yes, the AAV would be external.

 

[fuzzy]

The pipe rises vertically from the existing ground floor toilet and vents there, at a height of approximately 4m. I want to branch it about 2.3m up, leaving the original vent in place but creating a substack (?) approximately 3.3m away to service the new bathroom, and it is on the top of this that I'm looking to use the AAV which will be external.

So, this would be a second vent, and yes, the AAV would be external.

i see - second vent can be an AAV no problem, but last time i checked AAV's cannot be used externally. I would try to fit the AAV internal or extend up and just use as normal vent. Thats unless the new vents state can be used outside?

 

[buffster]

i see - second vent can be an AAV no problem, but last time i checked AAV's cannot be used externally. I would try to fit the AAV internal or extend up and just use as normal vent. Thats unless the new vents state can be used outside?

I can't extend it as a normal vent due to attic windows which are within 3m of wherever I could extend the soil pipe. I must admit I thought AAVs had to be internal until I found the one in the link I posted for an external one, but as it is a newish product I thought I'd sound things out here to see if anyone had any experience with them. Basically an external AAV would be much easier to install than an internal one, but would like to hear from someone who knows what they are on about rather than me being an enthusiastic amateur.

 

[john.bell55]

If your branch is less than 6m, do you need a second vent stack.
See below link to download Part H Building Regs
[DLMURL]http://www.burnley.gov.uk/site/scripts/download_info.php?fileID=1979[/DLMURL]
Cheers
Jack