The number of high end custom homes in the area keeps rising. Millions are spent on every luxury, though often there is very little focus on energy savings and home health. With all the information now available about a building effect on it’s occupants, savvy customers will start looking for contractors who also share their concern for their family’s health. Designers and building codes don’t always create healthy structures.
Radon exposure is the #2 cause of lung cancer deaths in the US according to the EPA and CDC. It is inevitable that people will be exposed to some levels of radon as it is in the outside air. It becomes a problem when we construct a building that traps this gas. It is heavy and comes from the earth, so it will settle to the lower level of a home and be less concentrated in upper levels. A short term measurement (2-7 days) will give you an average measured in picocuries. If levels are 4.0 picocuries or higher, mitigation is recommended.
The area a home is built has a part in whether it will have high radon. The Tahoe Truckee Area has a high incidence of elevated radon. There are some radon tests that can be performed on the site, though often provide little insight to determine a home’s radon potential.
Often a more significant component is how the home is built. If you build energy efficient homes and follow the building code for living space ventilation, then you likely are building an unhealthy home. The inside of a home should breathe as if it was alive. Most homes have an array of exhausting devices including bathroom exhaust fans, kitchen hoods, water heaters, furnaces, clothes dryers and wood stoves. All of these items remove air from the home envelope. So where does the air come from that replaces the exhausted air? Unless you didn’t seal the windows correctly, it will likely come from the underfloor/soil.
ERV Energy Recovery Ventilators or HRV Heat Recovery Ventilators are effective ways to bring in fresh air. A component to healthy home construction, these devices won’t ensure that a home is free of elevated radon. To build a home that is resistant to radon, one will need to install a passive radon system. This often can be done during construction at a cost of less $1,000. It requires that power be brought to a location where a radon fan would be installed if needed, and that PVC plumbing be installed during rough to be brought to a crawlspace or installed below a slab. Given the areas radon potential, all good builders should be incorporating passive systems into their homes.