Special attention needs to be paid to sealing joints in ducts and plenums passing through unconditioned spaces. Reducing the stack effect will not only limit radon entry but will make a home more energy efficient. Limiting entry routes and reducing the stack effect in homes play central roles in radon resistant new construction. The same strategy can be used with retrofit applications but the process is more difficult and foundation modification may not be an option. Retrofit radon control systems typically rely on the fan and pipe system described in items 4 and 5 above.
Prevention Pays Using radon resistant new construction practices makes good sense.
But there are other advantages to using radon resistant building practices. The extra attention to foundation sealing and limiting stack effect allows less outside air and less moisture into the home. Radon resistant homes may also be more marketable. This is especially true for areas in NC with higher radon potential like the piedmont and mountains. Controlling radon in new construction does not require exotic materials or unfamiliar building practices.