Radon outlet: access needed?

[ToughButterCup]

After forgetting it was there, and starting to lay the path around the outside of the house, I rediscover our radon outlet. 

 

I feel like ignoring it, but I suppose I'd better cover it with a rodding eye cover hadn't I?

 

Or can I just ignore it and just lay the path over the top of it. 

 

She Who Must Be Obeyed suggests we just put a large plant pot there.

 

You decide,  please would you? I'm just too knackered and frankly I can't be ar@ed.

[ProDave]

Isn't it to vent radon gas so should it not be open?  Where does it actually go?  What happens if it is so open rainwater gets in?

[Big Jimbo]

No idea. Sorry. But the path edge is going to be nice if that helps.

[saveasteading]

It has to be free to air and best to have a rain cap.  Is there only one such? It is best to have one each end of a porous pipe under the building.

[ToughButterCup]

Its just a pipe laid to a radon sump under the middle of the sitting room floor, about 500mm below my feet as I write (below FFL).

Rainwater? Hmmm, hadn't thought of that.

 

2 minutes ago, saveasteading said:

It has to be free to air and best to have a rain cap.  Is there only one such? It is best to have one each end of a porous pipe under the building.

 

Christ I have to give it  wee bonnet as well now ? Jesus. The BR spec says it has  to be vented above ground.

I suppose I ought to dig down now - while I still can without too much bad language -  shorten the pipe and bring it to the surface just behind (inside) the brick edging. 

Oh Lord ... rats ... how to prevent ingress? 

[BotusBuild]

My groundworker said the pipes will just fill up with water, you've ticked the BC boxes, as long as you can show you have a way to blow the "heavier than air" Radon out of the pipes if needed, you're good to go 🤣.

So, cap it, leave it.

[ProDave]

26 minutes ago, BotusBuild said:

My groundworker said the pipes will just fill up with water, you've ticked the BC boxes, as long as you can show you have a way to blow the "heavier than air" Radon out of the pipes if needed, you're good to go 🤣.

So, cap it, leave it.

In @ToughButterCup case could you not run the pipe underground horizontally with a slight fall and vent it out further down the slope, that would let the heavier than air gas out.

[saveasteading]

Don't just tick the box. This is radioactive gas that could build up in your house. 

It is necessary that the gas exits the vent rather than sit in the pipes.

A continuous pipe with 2 vents will create a draught.

Any outlet to air will allow pressure release, and the idea is for the pipe to be an easier route than any gap in the membrane.

To keep the rain out there are hoods, or put on a 90° bend.

But if a little rain gets in it might escape from a perforated pipe if used to collect gas.

[ToughButterCup]

On 22/08/2023 at 21:38, ProDave said:

.... run the pipe underground horizontally with a slight fall and vent it out further down the slope,...

 

Thats the best idea, I think.

It exits the house under the foundation  (1.5 m down) and i'm reluctant to dig that far. Since the gas is heavier than air, can I assume that its OK to expose the riser -say 300mm of it - put a 90 in, then a short traverse across the path and into a gabion wall .... ?

 

With an appropriate rodent barrier. The thought of rats under the house floor ....   I suppose I'd better check the radon sump first too - for all I know its full of water.

Inspection camera's on the shelf in the container  :  hardly ever need it, but when ya do, ya do.

[saveasteading]

8 hours ago, ToughButterCup said:

can I assume that its OK to expose the riser -say 300mm of it - put a 90 in, then a short traverse across the path and into a gabion wall .... ?

Sounds OK. The gas would have reached your barrier under pressure. Once it reaches your vent system it will only fill it under more of the same, then flow or dribble out to free air.

 

Can't you just bring it above ground and put a hat over it?

[dpmiller]

What is the level of radon risk locally- do you actually need a vent or is a barrier actually sufficient?

[ToughButterCup]

11 hours ago, dpmiller said:

What is the level of radon risk locally- do you actually need a vent or is a barrier actually sufficient?

 

I'm not sure . Our house falls only just within the one  grid square on the edge of a bigger area on the Radon map

 

 

I think that puts us in the 1 - 3% risk area.

 

We have a barrier in place

 

The risk appears to me to be minimal., therefore.  Quite why we were required to have a sump in there as well, I really don't know..

 

I took the cap off the sump pipe yesterday. Full of water.  So that means the sump is also full of water. 

That means pumping it - constantly.  At least there's unlikely to be rats down there

 

Stuff it. That's OFFICIAL

Edited August 25, 2023 by ToughButterCup

[dpmiller]

We were/ are in the same situation Ian- bordering the 1% and 5% lines. Local BC made no requirement so we chose to just go with membrane- if anything *does* rise and escape it'll get blown away

[BotusBuild]

On 23/08/2023 at 17:16, saveasteading said:

A continuous pipe with 2 vents will create a draught.

and this is what we have put in. All blocked while still building - to be vented later.

[SteamyTea]

19 hours ago, ToughButterCup said:

I think that puts us in the 1 - 3% risk area.

 

19 hours ago, dpmiller said:

bordering the 1% and 5% lines.

 

Pussies, we get the highest marks here.

 

[ToughButterCup]

Maybe that explains things.....

[SteamyTea]

26 minutes ago, ToughButterCup said:

Maybe that explains things.....

Explains why building ventilation is important, but also must not be wasteful i.e. MVHR.

Cornwall used to have extremely high incidences of lung cancer. This was put down to high levels of smoking. They dropped when buildings were retrofitted with radon control systems.

Edited August 26, 2023 by SteamyTea

[saveasteading]

[ToughButterCup]

So that's what magic mushrooms look like....