A radon mitigation system costs $1,200 to $2,000 on average with installation but can cost up to $2,500+ for larger homes. The total cost of radon mitigation depends on your home size and design and the type of system installed. An active soil depressurization system is the most common type installed in residential homes. However, other foundation-, wall,- and ventilation-based systems are available and may be required in houses where an active soil depressurization system isn't possible.

Radon is a radioactive gas that forms when radioactive metals like uranium, radium, or thorium break down in the soil, rocks, and groundwater. Radon is present everywhere in the earth. This colorless, odorless gas rises up through the soil and rocks and enters your home through tiny cracks and gaps in the foundation.

Because radon is everywhere, you are constantly exposed to low levels of it, and it is typically not harmful at those low levels. However, when radon is trapped in your home and becomes concentrated enough, it becomes a serious health risk. Exposure to elevated levels of radon is the second leading cause of lung cancer.

An active soil depressurization system is the most common type of radon mitigation system installed in residential homes. This type of system features a pipe installed in the basement, crawl space, or slab. A fan inside the pipe continuously suctions the soil to pull radon gas from below the foundationand draw it upward through the pipe before it enters the home. The system vents the radon gas above the home's roofline where it is not dangerous.

If a radon test shows levels in your home are above 4.0 picocuries per liter of air (pCi/L), a mitigation system is worth it to protect you and your family from lung cancer. A properly installed mitigation system can reduce radon levels by up to 99%.

If you are planning to sell your home, installing a radon mitigation system is worth it to make the home more appealing to potential buyers. Because you are required to disclose if your home has elevated levels of radon, most buyers will not purchase the home unless a mitigation system is installed.

The home seller is not legally obligated to pay for a radon mitigation system, but most sellers are willing to pay to have one installed in order to make their home more appealing to potential buyers. However, the buyer and seller may negotiate the terms of this arrangement.

The exhaust fan in a radon mitigation system typically lasts 5 to 10 years, but may last longer depending on the system's design, placement, and weather exposure. Most manufacturers include a 5-year warranty on the fan if the system is installed by a professional radon mitigation specialist. The piping can last 20 to 50+ years.

Follow these guidelines when evaluating radon mitigation specialists:

• Get 3 or more estimates for similar mitigation systems to compare.
• Look for specialists certified by the National Radon Proficiency Program (NRPP) or the National Radon Safety Board (NRSB).
• Choose licensed, bonded, and insured mitigation companies that have been in business for 5+ years.
• Ask the companies for local references with contact information.
• Confirm their estimate includes follow-up testing to ensure the mitigation system is working.
• Never pay in full before installation begins. Make a partial deposit instead and request a receipt.

Ask these important questions when hiring a radon mitigation company:

• How many radon mitigation systems have you installed in the past year?
• Are you NRPP or NRSB certified?
• How much do you charge for the initial radon test and inspection?
• What type of mitigation system do you recommend for my home, and why?
• How much will the system reduce the radon levels in my home?
• Does the installation cost include follow-up testing to ensure the system is working effectively?
• Does the installation include a digital monitor to track radon levels throughout the year?
• How long will the mitigation system last?
• What maintenance will the system require?
• Do you offer a warranty? If so, what does it cover?