Radon mitigation retrofit - impact on home efficiency?
March 24, 2022 10:22 PM Subscribe
We're under contract on a great house, but we're having trouble thinking through the implications of the potential need for radon mitigation. One of the features of the house is that it is LEED platinum certified, and we're concerned that a mitigation retrofit might reduce the house's efficiency.
The house has a heat recovery ventilator system installed, but it's currently unclear whether it was on during the radon testing. I know this would impact the results; however, we're trying to consider all the potential scenarios, including if we end up needing additional mitigation measures installed.
I'd appreciate any input, but I'm especially interested in hearing from homeowners with green/energy efficient homes who have had a mitigation retrofit about how it impacted your home's efficiency, or folks with applicable skillsets/experience in radon mitigation, particularly in green buildings. I'd also appreciate links to resources about efficiency loss in mitigation scenarios (we've read a number of links about general mitigation methods, and we're trying to understand potential impacts).
The house has a heat recovery ventilator system installed, but it's currently unclear whether it was on during the radon testing. I know this would impact the results; however, we're trying to consider all the potential scenarios, including if we end up needing additional mitigation measures installed.
I'd appreciate any input, but I'm especially interested in hearing from homeowners with green/energy efficient homes who have had a mitigation retrofit about how it impacted your home's efficiency, or folks with applicable skillsets/experience in radon mitigation, particularly in green buildings. I'd also appreciate links to resources about efficiency loss in mitigation scenarios (we've read a number of links about general mitigation methods, and we're trying to understand potential impacts).
There are a number of articles about radon on Green Building Advisor, including this one about installing a radon mitigation system in a passivehaus.
I would never ever trust something written by the Cato Institute, a right wing libertarian think tank.
posted by rockindata at 4:55 AM on March 25, 2022 [5 favorites]
I would never ever trust something written by the Cato Institute, a right wing libertarian think tank.
posted by rockindata at 4:55 AM on March 25, 2022 [5 favorites]
Response by poster: To clarify, the building was remodeled to LEED standards in 2010. It wasn’t a new construction.
posted by bluloo at 7:34 AM on March 25, 2022
posted by bluloo at 7:34 AM on March 25, 2022
Oh jeez didn't realize the article was Cato. I remember reading similar and more modern from other sources.
posted by bbqturtle at 10:01 AM on March 25, 2022
posted by bbqturtle at 10:01 AM on March 25, 2022
Response by poster: Should have included this in my last update, but we did review the articles on Green Building Advisor, but didn’t see info that spoke specifically to our concern about efficiency loss.
posted by bluloo at 10:45 AM on March 25, 2022
posted by bluloo at 10:45 AM on March 25, 2022
If it's outside the building envelope (drainage pipes under a slab, using a sump pit, etc) efficiency loss will be limited to the fan power usage.
If it's sucking conditioned air outside, then energy usage can be high, partially mitigated by ERV.
posted by flimflam at 8:40 PM on March 25, 2022
If it's sucking conditioned air outside, then energy usage can be high, partially mitigated by ERV.
posted by flimflam at 8:40 PM on March 25, 2022
Best answer: Building on flimflam's answer . . . I used to work for a radon mitigation company. The radon mitigation system's exhaust fan uses about 90-150 watts. When the radon mitigation system is installed, all the visible cracks in the foundation floor and joint between the wall and floor are sealed with caulk. This passively prevents radon gas from leaking into the basement. It also prevents the mitigation system's exhaust fan from sucking out heated or A/C air. Practices may have changed since I left the industry several years ago but when the house is tested, all fans and HVAC system are turned off if possible and windows and doors are kept closed for the duration of the test. Turning off fans and HVAC provide a worst case scenario for analysis. Open windows, exhaust fans and HVAC draw (how people actually live in their houses) in fresh air reducing radon. Before your contractor departs after installing the system, look for any holes he cut in the floor and basement walls to be filled with caulk or spray foam.
Thank you for wanting to keep your house's efficiency as high as possible.
posted by dlwr300 at 8:43 AM on March 26, 2022 [1 favorite]
Thank you for wanting to keep your house's efficiency as high as possible.
posted by dlwr300 at 8:43 AM on March 26, 2022 [1 favorite]
This thread is closed to new comments.
But also - how high are the levels? If you don't have a small child in the basement, I might ask that the radon remediation be installed (so you don't need to install it for the next buyer) but then you turn it off. This article takes the concept a bit far (I'm skeptical radon is good for you) but I've heard the premise of this argument and the sketchy background of the "war on radon" quite a few times.
https://www.cato.org/commentary/should-homeowners-consider-radon-threat-false-alarm
posted by bbqturtle at 4:19 AM on March 25, 2022