Radon-Reducing New Construction (RRNC)
Reducing Radon When Building a New Home
There are effective and cost-efficient steps to take during the initial construction of a home that significantly reduce the potential for high levels of radon. Many builders routinely include these features in some of their homes. If incorporated at the time of construction, radon systems can be hidden and not visible in the finished home. If a buyer is considering the purchase of a lot on which to build, he or she may want to consider having the builder incorporate a passive radon system. A new home constructed with a passive system must still be tested after completion.
Ask your builder about these features. If they do not use them, ask your builder to include them in your new home.
Tell your builder about EPA's document "Building Radon Out: A Step-by-Step Guide on How to Build Radon-Resistant Homes." Your builder can also work with a qualified radon mitigation contractor to design and install radon-reducing features. The cost to include radon mitigation features in a new home when it is being built can vary widely, but this should be a minimal increase.
When Should Radon-Reducing Construction Techniques Be Considered?
Currently, there are no statewide regulations in Nevada that require radon-reducing construction. However, the Nevada Division of Public and Behavioral Health encourages builders to voluntarily use radon-reducing construction in areas of high radon probability (red and orange areas) within the state as shown on the Radon Potential map below. As radon and geology do not follow county lines an individual building a home may want to consider radon-reducing construction techniques wherever they are building.
Find out if you are buying a home in a high radon area. Cooperative Extension’s map of Nevada test results indicates areas having the greatest potential for elevated indoor radon readings. Homes in places with high potential should be built with radon-reducing features. Contact the Nevada Division of Public and Behavioral Health, Radiological Health Section at 775-687-7550 or the Nevada Radon Education Program at 1-888-RADON10 (888-723-6610) to learn whether radon-reducing features are recommended or required in your area.
If you are planning to make any major structural renovation to an existing home, such as converting an unfinished basement area into a living space, it is important to test the area for radon before you begin the renovation. If your test result indicates a radon problem, radon-reducing techniques can be inexpensively included as part of the renovation. Because major renovations can change the level of radon in any home, always test again after work is completed.
The Benefits of Radon-Reduction Techniques
There are many benefits to including radon-reducing features in your new home including:
- Make your home safer from radon: These construction techniques help block radon from entering the home. The occupants will benefit from lower radon levels in their new home.
- Reduced costs: It is easier and less expensive to build radon-reducing features into a house during construction than it is to fix a radon problem later. Radon-reducing features are easy to install using common building materials.
The cost to a builder of including radon reducing features in a new home during construction can vary widely. Many builders routinely include these features in some of their homes. Some construction companies successfully use this as a marketing advantage. The cost to the builder of including these features is typically less than the cost to mitigate the home after construction.
The cost to install a system in a new home is much lower than adding the entire system after the building is completed. The average cost to install radon-reducing features in an existing home is $1,200. The average cost to install radon-reducing features in a new home during construction is $500 (a 58% savings).
If high radon levels are found in the new home (every new home should be tested for radon after occupancy), the techniques allow for easy and inexpensive installation of a fan for increased radon reduction in the home.
- Easy upgrades: Every new home, even homes built with radon-reducing features, should be tested for radon after occupancy. If high radon levels are found in the new home, the techniques allow for easy and inexpensive installation of a fan for increased radon-reduction in the home.
- "Greener" home: Radon venting features are easy to install at the time of construction and are one of a number of actions you can take to make your whole house healthier and "greener."
- Energy savings: Sealing cracks and other openings in floors and walls in contact with the ground help to reduce radon and may reduce your utility bills by preventing the loss of heated or cooled air.
- Reduce other indoor air quality issues: Radon-reducing features can also lower concentrations of other soil gases and decrease moisture problems.
What Are Radon-Reducing Techniques?
The techniques vary for different foundations and site requirements, but the basic elements are:
- A. Gas Permeable Layer - This layer is placed beneath the slab or flooring system to allow the soil gas to move freely underneath the house. In many cases, the material used is a 4-inch layer of clean gravel.
- B. Plastic Sheeting - Plastic sheeting is placed on top of the gas permeable layer and under the slab to help prevent the soil gas from entering the home. In crawl spaces, the sheeting is placed over the crawl space floor.
- C. Sealing and Caulking - All openings in the concrete foundation floor are sealed to reduce soil gas entry into the home.
- D. Vent Pipe - A 3- or 4-inch gas-tight or PVC pipe (commonly used for plumbing) runs from the gas permeable layer through the house to the roof to safely vent radon and other soil gases above the house.
- E. Junction Box - An electrical junction box is installed in case an electric venting fan is needed later.
Who Can Install Radon-Reducing Features?
Talk to your builder about installing a radon-reduction system during major renovations or new construction. Radon-reducing features can be easily and inexpensively installed with common building practices and materials. There is usually no need to hire a special contractor or architect. Many builders already incorporate some of these steps in the construction of their houses to control moisture or increase energy efficiency. Your builder can obtain architectural drawings for radon resistant features from EPA's Web site.
To learn more about building homes with radon-reducing techniques:
- Visit EPA's Radon-Resistant New Construction Web site.
- Builders can obtain the industry standard ASTM E1465 for radon control options in new construction by visiting www.astm.org.
- Read EPA's "Building Radon Out: A Step-by-Step Guide on How to Build Radon-Resistant Homes".