radon barrier

paulmallon

can i use heavy guage plastic sheeting for a radon barrier?
some builders suppliers say its used for radon barrier

My understanding is that it has to be certified to be used as a radon barrier, a building inspector/supervising engineer is unlikely to sign it off.

sinnerboy

only use an iab certified radon barrier

get help to install it

ensure it is overlaped well and taped at roll edges

ensure it is well sealed where pipes and ducts pass through it

make sure that when it turns horizonatl to vertical that it does so tightly leaving no air pockets behind for radon to gather - pay particulat attention to corners - remember - lap / seal/no voids behind . easier said than done - therefore look for help

also - radon sump in hardcore bed - omit 1/2 block to inernal rising walls every 1350 c/c at hardcore bed level - reason - so the sump serves entire floor area . if you dont do this you are only venting to the space you locate the sump in

muffler

sinnerboy wrote: »

only use an iab certified radon barrier

get help to install it

ensure it is overlaped well and taped at roll edges

ensure it is well sealed where pipes and ducts pass through it

make sure that when it turns horizonatl to vertical that it does so tightly leaving no air pockets behind for radon to gather - pay particulat attention to corners - remember - lap / seal/no voids behind . easier said than done - therefore look for help

also - radon sump in hardcore bed - omit 1/2 block to inernal rising walls every 1350 c/c at hardcore bed level - reason - so the sump serves entire floor area . if you dont do this you are only venting to the space you locate the sump in

Spot on once again sinnerboy.

doyler2

Hi Paul,

You can use it if it has an IAB Certificate to say that it can be uses as a radon barrier.

It is also important to test your house for radon after the construction is complete, as there is no guarentee that the barrier is working, and the only way to be sure is to test.

Make sure that the sump is installed correctly as this can be more important than the barrier. The sump does nothing until you test your house. If you find that there are high radon levels there, then the sump can be activated by connecting an extraction fan to it, which should reduce the radon levels to below the reference level. If the sump is not installed correctly, it could cost nearly twice as much to get rid of the radon.

Best of luck with the build.

grassynoel

Blocklayer just started rising walls today. Saw this thread to look into leaving holes in internal rising walls to allow potential radon to collect in sump. I checked out 'Radon Corrective Options' which said that if theres a 'doubt about permeability of hardcore' and the house is greater than 250m2 or 15m from the sump then set up an internal interconnected sump system or leave opes in the internal rising walls.

Should I be doubting the permeability of my hardcore????? I couldn't find guidance for sizes and regularity of leaving openings. I would like to get this right at this stage otherwise the Radon Protection System might be fairly useless but don't want to be driving the blockie mad with theoretical stuff either. Need an answer by bright and early in the morning,Any advice lads, (should have had this better planned I know). Thanks

sinnerboy

use 2 sumps and leave opes in rising walls at hardcore bed level

Mellor

always leave hole in the rising walls for radon,
and the more sumps the merrier, some houses easily need three

endplate

holes weren't put into the rising walls in my foundations but instead all the internal rooms will have a sump interconnecting pipe going into it

muffler

endplate wrote: »

holes weren't put into the rising walls in my foundations but instead all the internal rooms will have a sump interconnecting pipe going into it

Not a problem with that but its an awful lot of sumps and I hope that they were also used in hallways etc.

whowantstwoknow

Hi all,

I got an extension completed last year. The extension consisted of 2 additional slabs. Now each stab eventually had a 4 inch waven pipe sticking up on the outside of the slab with a cap on top. I asked the builder what these were and he mentioned radon etc. I assume it was all done correctly etc :rolleyes:

Anyhow my question is on one of these external pipes (I guess/hope this is the sump) I intend to overlay a small wooden decking. I will still have access to the pipe as the decking will only be screwed. Should those caps be completely sealed? I ask as my dad (being from the old school/generation) got it in his head the idea that something must be ventilating from the pipe and went ahead with a drill and made some holes!!!

So if this isnt right/OK I want to replace the existing cap before I commence with the decking.

Thanks

Mike

muffler

madunphy wrote: »

Hi all,

I got an extension completed last year. The extension consisted of 2 additional slabs. Now each stab eventually had a 4 inch waven pipe sticking up on the outside of the slab with a cap on top. I asked the builder what these were and he mentioned radon etc. I assume it was all done correctly etc :rolleyes:

Anyhow my question is on one of these external pipes (I guess/hope this is the sump) I intend to overlay a small wooden decking. I will still have access to the pipe as the decking will only be screwed. Should those caps be completely sealed? I ask as my dad (being from the old school/generation) got it in his head the idea that something must be ventilating from the pipe and went ahead with a drill and made some holes!!!

So if this isnt right/OK I want to replace the existing cap before I commence with the decking.

Thanks

Mike

The pipe should be capped/sealed. If you intend putting something over it then you should leave access to it.

The idea is that you should get your house tested at some point for radon gas. If its detected you then remove the cap and extend the pipe up to and above the eaves and have a mechanical extractor fan fitted to it.

I think you should just extend the pipe now and recap it above the eaves and then run a test later.

timmer3

just hijacking this thread with a radon barrier question....
i'm nearing the end rennovating a 1940's mass concrete house in dublin 12. i'm in the 1-5% category on the radon map, and haven't got the house tested. the ground flooring consists of joists with boards on top. there are wall vents at front and back for the ground floor. i have ordered 14mm solid oak boards to overlay for the ground floor. i didn't go for an air-tight house in the end, but would like to put in some good draught proofing for the floor. there is some radon barrier selling on adverts.ie that caught my eye. thought it could work for draughts, radon and damp.
this is a total DIY suggestion, and at this stage i don't have the €1000 to get it professionally installed and certified, but would it work to install the radon barrier between the 2 sets of floorboards, and tape/seal it, either direct to the concrete walls, or to the plaster board behind skirts. the new floor boards will be hidden screwed in, which would puncture the barrier at each point. i think it's not right to seal it to the plaster behind the skirting boards because the plasterboard is on batons all around so gas could work its way up the walls and under the upstairs floor and beyond.

i have some joist repairs to do anyway so it's not a great stretch to consider lifting all the boards and joists, and install the barrier to the base. i take into account what sinnerboy wrote at the start of this thread, and would appreciate any comment on the feasability of a DIY install.

Out Of Order

I'm afraid I can't help you timmer but I'll throw another question to the experts:

What about combining the radon sump with the external feed into a room-sealed stove?
i.e. pipe over ground goes under slab into sump, and then through slab into room-sealed stove, and then up flue through roof.

The draw from the stove would be extracting radon (if there is any) from the foundation on a continuous basis. Would this be any advantage?

sas

Out Of Order wrote: »

The draw from the stove would be extracting radon (if there is any) from the foundation on a continuous basis. Would this be any advantage?

Given that in reality there is no such thing as a 100% room sealed stove you could be actively pumping radon into your house.

I understand the thinking but I'd have concerns.

sydthebeat

Out Of Order wrote: »

The draw from the stove would be extracting radon (if there is any) from the foundation on a continuous basis. Would this be any advantage?

most definitely no....

the primary function is to get any possible radon away from the internal of the dwelling in the first instance.

An accurately installed radon membrane will do this. The radon sump outlet is increase significantly high levels are found in the area which would require continuous pumped extraction.

In my opinion the installation of a home radon testing kit in every dwelling should be part of the building regulations. Much more accurate radon mapping could then be possible... IMHO the 10K grid mapm used at the moment is not at all accurate enough to make any kind of a determination.

sas

Is a well performing HRV unit likely to contribute to the removal of radon?

Out Of Order

sydthebeat wrote: »

most definitely no....
the primary function is to get any possible radon away from the internal of the dwelling in the first instance.

OK,
Thanks Syd

sydthebeat

sas wrote: »

Is a well performing HRV unit likely to contribute to the removal of radon?

not sure... MHRVs are supposed to be set to mimic natural ventilation so in theory it shouldnt make a difference

just surmising here but:

a system running at positive internal pressure make work better than one set to slightly negative internal pressure.
again, the main idea is not to let it in in the first place. If there is radon ingress, it will be continuous... the rate of ingress obviously equates to the amount of radon in the area. If the rate of ingress even matchs the negative pressure of the MHRV, then thats a continuous exposure to what could be very serious levels of radon.
If the system is set to positive pressure could that pressure keep the same amount of radon from entering the dwelling??? ... i dont know...

I rather get the installation of the sump and membrane perfect.... get a radon tester... and then if needs be... get a continuous external pump...

prevention is better than cure.