What to consider when building your dream home to remove Radon.
Building your dream home is a big process. Everything you choose is carefully thought out and finishes matched together. It is not always what you see on the outside that is important, but inside the walls is very important as well.
Radon systems are usually not thought about until after the house is done and not before. However, many builders are providing the option of a Radon System already installed in the home. These systems are called a “Passive System” or RNCC (Radon Resistant New Construction).
What is Radon?
Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil, rock, and water. You cannot see or smell radon. High levels above 4.0 pCi/L of Radon can be found in 1 out of 15 homes in the US. Colorado was just upgraded to a Zone 1 which means 50% of homes in Colorado have high levels of Radon.
Air pressure inside your home is usually lower than pressure in the soil around your home’s foundation. Because of the difference in pressure, your home acts like a vacuum, drawing radon in through the cracks and other openings of the foundation. This is considered the stack effect which is temperature-induced pressure differentials. This means hot air rises and will make its way out through the top of the house. Make-up air is drawn in from under the bottom level of the home and with that make-up air, radon enters the home.
What is a Passive System?
When a Passive System is installed during the build there is a suction point created through the slab of the basement or lowest level with 3” PVC pipe. This suction point will create a pressure barrier to remove soil gases including Radon. The PVC pipe will run up through the walls and vent out of the attic. Sometimes that will be enough to bring your level below the EPA recommendation of 4pCi/L. Majority of the time the system will need to be activated.
What does that mean?
When the home is finished with construction you will want to get your home tested to determine your levels. If it is above the EPA recommendation of 4.0pCi/L you will want to activate your system by having a fan connected to the PVC pipe in the attic for the passive system. Once that is complete the system now becomes an “Active System”. This requires the Mitigation Technician to remove 12-14” of the system in the attic to place the fan.
If you have a “Passive System” make sure you are testing and getting the system inspected within your warranty period to ensure it can become an active system some point in the future. Majority (75% or more) of the passive systems are installed by the plumber and not a Certified Radon Mitigation Technician. Many systems are not able to be activated on the first trip because the piping isn’t accessible due to overbuild or there isn’t enough vertical piping running up to the roof to remove piping and insert the fan. That would require creating a new vent in the roof and piping rerouted. Majority of the time warranty will cover what needs to be changed or fixed for the Technician to activate your system.
We are NRPP and AARST Certified Radon Mitigation and Testing Technicians. We will work with you and your builder to make sure the system is up to code and properly working to keep you and your family safe in your dream home!