Why Buy or Construct a Radon-Resistant Home?
- The Techniques Work
Simple and inexpensive techniques reduce Radon levels by up to 50% as a passive system (without the use of a fan) at the time of construction. This method may not only lower Radon gas but, also lower levels of other soil gases and decrease potential moisture problems.
- It’s Cost Effective
Building in the features is much cheaper than fixing a Radon problem later.
- Save Money
The techniques described here also make your home more energy efficient and could provide you with lower energy costs. These systems can be very effective in reducing Radon levels passively (without the use of a fan).
- Upgrading is Easy
If high levels of Radon are found, a fan can easily be installed as part of the system for further Radon reduction.
How Do Costs Compare?
Average cost to install a Radon mitigation system in an existing home:
Average cost to install Radon-resistant features during new home construction
What are Radon-Resistant Features?
The techniques may 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. This gas-permeable layer is used in homes with basement and slab-on-grade foundations; it is typically not used in homes with crawlspace foundations.
B. Plastic Sheeting
Plastic sheeting seams sealed is placed on top of the gas permeable layer and under the slab to help prevent the soil gas from entering the home. In crawlspaces, the sheeting is placed over the crawlspace floor.
C. Sealing and Caulking
Membrane and vapour barrier below-grade require sealing of all service pipe penetrations. As well all joints need to be sealed and all edges of the membrane must be sealed to the footings. If concrete is installed over the membrane, then all shrinkage gaps and any developing cracks require sealing after the concrete has cured.
D. Vent Pipe
A 4-inch ABS or PVC pipe (or other gas-tight pipe) 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 outlet within 6 feet of the vertical piping should be included in the attic at the time of construction to make the installation of a vent fan easier. For example, you decide to activate the passive system because your test result showed an elevated radon level (200 Bq/m3 or more).