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Radon Control Methods

VLADIMIR LEVIN

REGISTERED
Joined
Jun 11, 2019
Messages
136
Location
NY
In new construction, does the radon pipe need to actually penetrate the roof or can it be brought to the underside of the sheathing?
AF103.1 says its "...intended to prepare the building for post-construction radon mitigation, if neccessary"

Installing all the piping "prepares" the building, and if needed in the future a roof penetration can be made then.
 
If a pipe was installed during construction, wouldn’t that be done if the neighborhood had a history of radon? Or should all homes be built with radon protection “just because”?
 
It depends whether the jurisdiction has adopted Appendix F.
Virginia requires all counties which are identified as areas of high radon potential (IRC AF101 Zone 1) to enforce Appendix F.
 
In new construction, does the radon pipe need to actually penetrate the roof or can it be brought to the underside of the sheathing?
AF103.1 says its "...intended to prepare the building for post-construction radon mitigation, if neccessary"

Installing all the piping "prepares" the building, and if needed in the future a roof penetration can be made then.
There's a lot that goes into a radon mitigation system. Stopping at the underside of the roof sheathing seems wrong.
 
EPA Standards
 
A properly installed sub slab radon system will act as a passive vent and help quite a bit, and if radon levels are ever found to be higher than wanted through testing then the in line fan can be added. Seems crazy to not put it through the roof during construction.

"if necessary" my be as required by geographic area.
 
The internet states that every California county has radon. I have never seen a radon mitigation system. I’ve seen plenty of methane barriers and they are probably similar in makeup.
 
In new construction, does the radon pipe need to actually penetrate the roof or can it be brought to the underside of the sheathing?
AF103.1 says its "...intended to prepare the building for post-construction radon mitigation, if neccessary"

Installing all the piping "prepares" the building, and if needed in the future a roof penetration can be made then.
Well, if the code requires you to prepare only by installing the pipe were not accessible, then connecting the pipe between were it rises out of the slab floor to the riser to the attic would not be needed I guess because you can access it later and make the connection if need be. Its an open area right?

So lets say you don't penetrate the roof and exit the building, and now the pipe produces venting radon gas in the attic, after the new owner moves in?

So, with an existing home it has had time to produce a radon gas build up if present that can be tested for, prior to the sale.

How does one test on a new home?

Simple, plan for the worst to a minimum. The minimum is at least install a passive system, under slab to the exterior, aka out the roof.....

I would not want to be the one trying to explain why we saved the cost of diner for 2 and ended up with this...
 
Bringing it to just below the sheathing technically prepares the house, but I always recommend going through the roof during construction—it’s way easier and avoids future headaches if mitigation is needed.
 
I looked into what a radon system entails and I am not impressed. A methane barrier is also used to control a gas but there is a lot more involved. I understand that methane has explosive properties but the radon system is is just short of why bother.
 
I live and inspect in a high radon zone in Massachusetts, which adopted the passive system requirement for new construction. Given you cannot test for radon until the home is complete and empty for 3 days it seems to be a win. There is no building code requirement for testing for radon, usually the bank.

Prior to passive system installation requirements, I would do a final on a home, issue OC and be on my way, the following month back in the same neighborhood, the retrofit mitigation system would be installed on the outside of the new home, new electric fan and pipe, pretty ugly, mostly 2 story colonials built here. (no permits, not to be debated). probably $2000 to $2500

1746101554998.png

Currently a new home, stone under the slab, some pipe and a electrical outlet in the attic within 6 feet of the pipe. Can not say what percent of homes need depressurizing fan, can't see them any more.
 
Highly exaggerated phenomenon based on assumption and speculation and not scientific fact.
I could not disagree more on this. At one time, I was a licensed tester and informed, so I am familiar with radon. This is not just a US issue. Radon has been studied for decades, scientifically, with peer-reviewed studies by various agencies around the world. Micro studies in different regions of the country have led to larger studies, and we know we have hot spots for high levels that correlate with elevated lung cancer deaths not attributed to smoking, but the damage of the alpha particles inside the lungs. So no, not highly exaggerated based on an assumption. There is worldwide scientific proof of this.

Now, with that being said, in the US, the action level is very low at 4.0 pCi/L, vs Canada at 5.4 pCi/L, and much of Europe is the same as Canada. Germany, however, has an action level of 8.1 pCi/L. The action level in the US was based on an average, and not a level associated with health concerns. This conservative approach is a safety buffer, especially since radon mitigation of existing homes is relatively easy and inexpensive.

I believe that passive systems should be mandatory in all hot spots because they can be converted to active systems rather easily.
 
I live and inspect in a high radon zone in Massachusetts, which adopted the passive system requirement for new construction. Given you cannot test for radon until the home is complete and empty for 3 days it seems to be a win. There is no building code requirement for testing for radon, usually the bank.

Prior to passive system installation requirements, I would do a final on a home, issue OC and be on my way, the following month back in the same neighborhood, the retrofit mitigation system would be installed on the outside of the new home, new electric fan and pipe, pretty ugly, mostly 2 story colonials built here. (no permits, not to be debated). probably $2000 to $2500

View attachment 15550

Currently a new home, stone under the slab, some pipe and a electrical outlet in the attic within 6 feet of the pipe. Can not say what percent of homes need depressurizing fan, can't see them any more.
Exterior systems are rather ugly, but the fan in the attic is a great, approved alternative. The mistakes I see from DIYers are that they put the fan in the basement, which is a no-no.
 
I could not disagree more on this. At one time, I was a licensed tester and informed, so I am familiar with radon. This is not just a US issue. Radon has been studied for decades, scientifically, with peer-reviewed studies by various agencies around the world. Micro studies in different regions of the country have led to larger studies, and we know we have hot spots for high levels that correlate with elevated lung cancer deaths not attributed to smoking, but the damage of the alpha particles inside the lungs. So no, not highly exaggerated based on an assumption. There is worldwide scientific proof of this.

Now, with that being said, in the US, the action level is very low at 4.0 pCi/L, vs Canada at 5.4 pCi/L, and much of Europe is the same as Canada. Germany, however, has an action level of 8.1 pCi/L. The action level in the US was based on an average, and not a level associated with health concerns. This conservative approach is a safety buffer, especially since radon mitigation of existing homes is relatively easy and inexpensive.

I believe that passive systems should be mandatory in all hot spots because they can be converted to active systems rather easily.
Full passive system is a requirement in Canada in the 2025 code for all new construction homes.
 
Exterior systems are rather ugly, but the fan in the attic is a great, approved alternative. The mistakes I see from DIYers are that they put the fan in the basement, which is a no-no.
it's against the radon code.. but those fans are supposed to be sealed. ultimately.. from a personal perspective and not of an inspector.. as long as the crm test comes back good its all good
 
I could not disagree more on this. At one time, I was a licensed tester and informed, so I am familiar with radon. This is not just a US issue. Radon has been studied for decades, scientifically, with peer-reviewed studies by various agencies around the world. Micro studies in different regions of the country have led to larger studies, and we know we have hot spots for high levels that correlate with elevated lung cancer deaths not attributed to smoking, but the damage of the alpha particles inside the lungs. So no, not highly exaggerated based on an assumption. There is worldwide scientific proof of this.

Now, with that being said, in the US, the action level is very low at 4.0 pCi/L, vs Canada at 5.4 pCi/L, and much of Europe is the same as Canada. Germany, however, has an action level of 8.1 pCi/L. The action level in the US was based on an average, and not a level associated with health concerns. This conservative approach is a safety buffer, especially since radon mitigation of existing homes is relatively easy and inexpensive.

I believe that passive systems should be mandatory in all hot spots because they can be converted to active systems rather easily.
the story of how they found out about radon is interesting. a guy worked at a nuclear facility and was tested with a Geiger when entering and exiting work. They couldn't figure out why he had elevated levels going in to work. tested his home after that.. i think they had thought he was stealing initially
 
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