Radon Testing & Mitigation near you

There is nothing to look at. Radon is a gas that moves out of the soil and into a building through the paths that already exist: the gap where the slab meets the wall, sump openings, crawl space floors, utility penetrations, cracks and block cavities. Two identical houses on the same street can produce very different results, and a neighbor's number tells you almost nothing about yours.

It also varies with the season and the way you live in the house, which is why EPA specifies test conditions rather than leaving it to judgment. What decides your result is the pressure difference between the soil and the inside of the house, and that changes with weather, with the heating system running, with exhaust fans, and with whether the windows have been open. The practical consequence is that a valid test is a controlled test, and that a single reading taken casually in an open house in spring is not the number to make decisions on.

Because the numbers move, EPA treats testing as something you repeat rather than something you complete. Its guidance after a mitigation system goes in is to retest the home at least every two years to be sure radon levels remain low, and to retest again after major structural changes such as finishing a basement or adding a foundation for an addition.

Testing is cheap and widely available. EPA notes that many radon test kits can be found online or in home improvement stores, and suggests contacting your state radon program for information on obtaining a kit or finding a radon measurement professional. The state route is worth using even if you buy the kit yourself, because some states subsidize kits and all of them know the local geology.

Conditions matter more than the brand of the device. EPA specifies for a post-mitigation measurement that windows and doors must be closed 12 hours before and during the test, and that a two- to seven-day measurement is recommended for checking a system's effectiveness. The same logic of closed-house conditions applies to a short-term test used for an initial screening: the point is to measure the house as it is lived in during the heating season, not as it is ventilated on a mild weekend.

One test is a screening, not a conclusion. Where a short-term result comes back at or above the action level, the sensible next step is a follow-up measurement before committing to a mitigation contract, both because short-term results fluctuate and because the follow-up number becomes the baseline you will compare the post-mitigation test against.

There is a clear front-runner. EPA's consumer guide states that in homes with a basement or a slab-on-grade foundation, radon is usually reduced by one of four types of soil suction, subslab suction, drain-tile suction, sump-hole suction or block-wall suction, and that active subslab suction, also called subslab depressurization, is the most common and usually the most reliable radon reduction method. One or more suction pipes are inserted through the floor slab into the crushed rock or soil beneath, or below the slab from outside the home, with the number and placement depending on how easily air moves under the slab and how strong the radon source is. Often a single suction point is enough.

The variants exist for particular houses. Drain-tile suction works with either partial or complete drain tile loops. Sump-hole suction caps an existing sump so it continues to drain water while serving as the suction point. Block-wall suction depressurizes hollow block foundation walls and is often paired with subslab suction. Crawl spaces are usually handled by sealing a membrane over the soil and drawing from beneath it, or by ventilating the space, which in cold climates means insulating pipes, sewer lines and appliances against freezing.

The published effectiveness ranges are worth knowing because they explain the price difference between systems. EPA's table gives active subslab suction a typical reduction of 50 to 99 percent, drain-tile suction and block-wall suction the same 50 to 99 percent range, and passive subslab suction, which relies on natural pressure differences rather than a fan, only 30 to 70 percent, noting that passive systems may be more effective in cold climates but are not as effective as active ones at reducing high levels.

Sealing is the intervention homeowners reach for first and the one EPA specifically warns against relying on. Its consumer guide states that sealing cracks and other openings in the foundation is a basic part of most approaches to radon reduction because it limits the flow of radon in and makes other techniques more effective and cost-efficient, and also reduces the loss of conditioned air. Then it draws the line: EPA does not recommend the use of sealing alone to reduce radon, because by itself sealing has not been shown to lower radon levels significantly or consistently.

The reasons are practical rather than theoretical. EPA notes that it is difficult to identify and permanently seal the places where radon is entering, and that normal settling of a home opens new entry routes and reopens old ones. The same guide is similarly cautious about ventilation as a fix, observing that once windows, doors and vents are closed, radon concentrations most often return to previous values within about 12 hours, so natural ventilation should normally be regarded as only a temporary approach. Sealing belongs in the job as a supporting measure. It does not belong in the contract as the job.

EPA recommends using a certified or qualified radon mitigation contractor trained to fix radon problems, and tells homeowners to start with their state radon office, noting that many states require radon professionals to be licensed, certified or registered and to install systems that meet state requirements. In states that do not regulate radon services, EPA's advice is to ask whether the contractor holds a professional proficiency or certification credential and whether they follow industry consensus standards, naming ASTM E2121, the standard practice for installing radon mitigation systems in existing low-rise residential buildings. EPA recognizes two national proficiency programs, the National Radon Proficiency Program and the National Radon Safety Board, and states that it requires states receiving indoor radon grants to maintain and provide the public with a list of radon service providers credentialed through state processes or those programs.

The installation itself has checkable requirements. EPA's list includes that systems be clearly labeled to avoid accidental changes; that exhaust pipes of soil suction systems vent above the roof surface and 10 feet or more above the ground, and at least 10 feet away from windows, doors or other openings unless they vent at least 2 feet above those openings; that the exhaust fan not be located in or below a livable area; that an exterior fan meet local building codes for exterior use; that electrical connections follow local electrical codes; and that a warning device be installed to alert you if an active system stops working properly, placed where it can be easily seen or heard, with the contractor confirming it works.

EPA also suggests what belongs in the proposal before you sign: proof of state certification or proficiency credentials, proof of liability insurance, bonding and any licenses local requirements demand, diagnostic testing before the system is designed, installation of the warning device, testing after installation, and whether a guarantee to reduce levels to 4 picocuries per liter or below is offered and for how long.

This is the most quietly useful thing in EPA's guidance and it is rarely repeated by the industry. A post-mitigation radon test should be done within 30 days of installation, but no sooner than 24 hours after the system is in operation with the fan running. The contractor may perform that test to check the work and the initial effectiveness of the system, and EPA then says it is recommended that you also get an independent follow-up radon measurement, because having an independent tester perform the test, or conducting the measurement yourself, eliminates any potential conflict of interest.

It is a small expense against the cost of a system, and it is the only check on whether the thing you bought is doing what it was sold to do. Use the same closed-house conditions EPA specifies, windows and doors shut for 12 hours before and throughout, and a two- to seven-day measurement. Keep the before and after numbers together with the installation paperwork; they are the evidence a buyer's agent will ask for later and the baseline you will use at the next retest.

Radon systems are priced on how hard it is to get suction under your particular floor. The drivers are the foundation type and whether the house has a basement, a slab, a crawl space or a combination of all three, how easily air moves in the material under the slab and therefore how many suction points are needed, where the pipe can be routed to satisfy the discharge rules, whether the fan can be sited in unconditioned space, the electrical work required, whether diagnostic testing is charged separately, and whether crawl space membrane or block-wall work is part of the scope. EPA notes that contractors may charge for diagnostic tests even where the estimate is free, and that those tests help determine which method to use.

LokalMatch is the step before all of that. You describe the house once: the test result you have, the foundation type, whether there is a sump, and where the mechanical space is. Radon mitigation contractors covering your area receive the request and the interested ones contact you. There is no charge to homeowners, and pros pay for the requests they receive. LokalMatch does not test for radon, does not install systems, does not set prices, and does not vet, rank or recommend any contractor, so checking state credentials and arranging your own independent post-mitigation test remain yours.