Sump/ French Drain
A home with a sump or french drain system will typically require the least amount of work to mitigate effectively, though they do require additional parts and materials. A system of this type is typically the least costly way of mitigating, if it’s an option. These systems basically interconnect, either directly or through the sump, to the existing perforated piping around the foundation. This type of system will start at around $600-$800 to have installed.
A sub-slab depressurization type of system involves drilling a 5” hole through either the interior concrete basement slab vertically or through the stem wall horizontally from the exterior, below ground. Then 10-15 gallons of soil removed by hand to create a suction pit under the slab. This type of system requires considerably more work and equipment, versus a sump/ drain type system. These systems start at around $800-$1000 and go up if a larger fan, additional suction points, or extensive piping is required.
A passive system works by removing a constant amount of air from within your crawlspace and expelling any gasses above roof line. It is the least expensive type of system to install in a home with a crawlspace, but is not always sufficiently effective on its own. Depending on testing, a vapor barrier may need to be installed additionally. Passive mitigation systems are basically everything required for a vapor barrier system, without the vapor barrier. Perforated pipe is installed around the perimeter of the crawlspace and connected to an exterior radon fan to draw out gasses. A system can be installed and tested to determine if further work or adjustments will be required. An installed passive type system starts at around $600-$700
If you have a home with a crawlspace, and you want the lowest possible radon levels, the most effective and efficient system, and want your crawlspace to be clean, pretty and bright white, have a vapor barrier installed. We use a durable, fiberglass reinforced, 6 or 12 mil polyethylene barrier material, seal the perimeter, and mechanically fasten it with concrete nails and washers. This type of system is always going to be the most expensive, yet generally the most effective way of mitigating radon. Installing a vapor barrier requires a lot of work, and in addition there are a lot more materials involved compared with other systems. To have a vapor barrier system installed will start at minimum of about $1200-$1400 for a 1000-1200 square foot area, and about $400-$500 per additional 1000 square ft. ( crawlspace area )