Man Hole Covers and Stench Pipe

[robsartain]

I have a victorain terrace and a lean to has been built on the side which had a stench pipe (as I know it) or vent pipe. It also has another hole which was grated where the sink waste was fed in to.

So I have two questions regarding drainage:-

I have decide to use a Air Remitance Valve instead of a huge stench pipe. I have a 3inch pipe which fits the hole but what is the best way to seal the pipe into the hole ?

Second question is that I still have the sink waste going into the second hole but the waste enters from the side and not the top now. I want to put a cover on it so people don`t fall down the hole and also to stop nasty smells coming up. Am I best just covering the hole with Ply ? Do I not need to seal the hole some how to stop nasty whiffs coming up from the drains and into the lean to ?

As always any advice and sarcastic comments welcome.

[B17NNS]

Soil stacks are normally 4". What is your existing set up made of? Do you want to replace the existing stack back to ground level with a shorter pipe with a AAV on top?

The way to stop smells would be to install a bottle or back inlet gulley (basically a trap) but yo should already have one of these.

http://www.screwfix.com/prods/28956/Plumbing/Under...

[Simpo Two]

robsartain said:

I have decide to use a Air Remitance Valve

That's a great malapropism for 'air admittance valve'!

[Ferg]

It is neither legal, nor sensible to replace a soil vent pipe with an AAV in ALL circumstances. Is it solely a vent? If so I would suspect you can't replace it with an AAV.

[robsartain]

B17NNS yep thats exactly what I want to do.

It doesn`t sound like an AAV is the way to go. Thanks for the screwfix link.

So how do I go about sealing the holes ? or creating my own manhole cover ?