Renovating & radon barriers

gerryo

I apologise for starting a new thread on Radon, I've read several old ones;
I don't want to re-open ancient threads & those I've read, my question was not really answered.

I'm about to get a (early 60's) house renovated, Radon barriers have been discussed & advised. I'm aware of what's being done for new builds & it seems to make sense, lots of care needed, expertise & experience are essential.

What about renovating?

My current opinion is there is no effective way to radon proof a house unless it's either a new build or you tear it all down & start again. If you rip up old concrete floors & put down a barrier in an attempt to seal off the house, it's partially effective at best or a waste of money if not done right.

I'm thinking that if you try to seal off the downstairs rooms by placing a barrier underneath the floors in each room & then tape the barrier to the existing wall foundations, radon will seep up via the walls & your
efforts will either be a waste of time or best case you might reduce the amount of radon but it won't be near as good as a new build. So why bother?

Radon Barriers are us usually installed to run out under external walls, hopefully that's going to give a seal all the way under the foundations if there are no rips/tears. The sump is going to act as a collector
& will (if required) act as a conduit for radon rather than have it seep into the building.

Seems worthwhile for new builds, but in an existing build, if you can't put a barrier below the complete foundation, is it worthwhile doing anything?

Has anybody got empirical evidence that suggests attempting to radon proof an existing build does have merit, does work enough to make the cost worthwhile?

Regards
Gerryo

muffler

Have a read at this

Will23

suggest you get a radon test carried out first that should indicate if there is an existing problem in the building...

http://www.rpii.ie/Measurement-Services/Radon-Measurement/Services/Apply-For-Measurement-Online.aspx

unfortunately the test period is approx 6 months.

the testing agent should be able to advise on remedial works if required.

Will.

gerryo

Thanks Muffler, that is an interesting document.

Based on the information, it seems worthwhile getting it done as the the gas finds gaps & cracks to get in to buildings.
Assuming the work is done to a good standard it should be a significant improvement compared to leaving "as is".

gerryo

Will23 wrote: »

suggest you get a radon test carried out first that should indicate if there is an existing problem in the building...

http://www.rpii.ie/Measurement-Services/Radon-Measurement/Services/Apply-For-Measurement-Online.aspx

unfortunately the test period is approx 6 months.

the testing agent should be able to advise on remedial works if required.

Will.

Thanks Will

The test is underway, results take a while (as you mentioned) & we can't halt works until the answers come in. I'm assuming it's a problem, that needs fixing so will probably go ahead with the Radon barrier.

I was initially concerned the gas seeped into concrete, & taping a barrier to the existing sub floor portions of internal walls was not going to stop it rising up.

Seems this is not the case.

muffler

gerryo wrote: »

Thanks Muffler, that is an interesting document.

Based on the information, it seems worthwhile getting it done as the the gas finds gaps & cracks to get in to buildings.
Assuming the work is done to a good standard it should be a significant improvement compared to leaving "as is".

Any remedial work carried out is an improvement. There are loads of "specialists" out there who would undertake this work or if you/your contractor feel confident enough then fire away.

Getting tests done before and after should show significant changes in the results.

Johnwaterford

Hi noticed you mentioned getting the radon barrier stuck to the sub floor wall. Just wondering what you use to actually stick it to the wall. Am renovating 60s cottage aswell but cant find info about what to use to stick barrier to wall and get a good seal

gerryo

Johnwaterford wrote: »

Hi noticed you mentioned getting the radon barrier stuck to the sub floor wall. Just wondering what you use to actually stick it to the wall. Am renovating 60s cottage aswell but cant find info about what to use to stick barrier to wall and get a good seal

I don't know what was used, the builder did the job without telling me the exact details.
I believe it was taped, but not sure what type of tape was used.
The barrier is below the underfloor insulation, so is probably taped to the sub foundations.

I did participate in a local radon survey prior to commencing building, the one month results were:-

Living Area 209 Bq/m^3 (ground floor)
Bedroom 74 Bq/m^3 (first floor)
seasonally adjusted average 147 Bq/m^3

Irelands Average is 89 Bq/m^3 but 147 Bq/m^3 is still well below the action limit of 200 Bq/m^3. This one month test isn't readily used in Ireland yet but It's very unlikely that the 3 month test would be over 200 Bq/m^3 with a one month reading so low.

I never did get a follow on radon test done to see how much difference the barrier makes

Gerryo