Selling a Maryland house with a high radon reading: the disclosure form, the Montgomery County test rule, mitigation, and what a cash buyer does with the number

Radon shows up at the worst moment. A buyer’s inspector leaves a monitor in the basement for two days, the number comes back above the level the EPA says to act on, and a contract that was moving suddenly has a new addendum. Or you tested on your own before listing and now have a report you cannot un-know. Either way the gas itself is the easy part. What makes radon a seller problem in Maryland is a county rule, a disclosure form, and a buyer who wants someone else to pay for the fix. This article covers all three and ends with the sale that skips them.

Why Maryland basements test high

Radon is a gas that rises out of the ground as uranium in rock and soil breaks down, and it collects in the lowest closed level of a house. The EPA’s action level is four picocuries per liter, and much of central Maryland sits on the kind of geology that produces readings above it. The EPA map puts Montgomery, Howard, Frederick and Carroll counties in its highest potential zone, and basements from Bethesda to Westminster test high often enough that local inspectors treat a reading above four as routine rather than alarming. A house with a finished basement that someone sleeps in matters more than a house with a dirt crawlspace, and a reading taken in February with the windows shut usually runs higher than one taken in July.

The one county that makes you test

Maryland has no statewide law requiring a radon test at sale. Montgomery County does. Section 40-13C of the county code says a single family home, detached or attached, cannot settle unless a radon test performed less than a year before the settlement date has been shared between the parties. Either side can run it. Condominium units are exempt, and so is a sale by a personal representative of an estate, along with the other transfers the rule carves out. A seller in Silver Spring or Rockville who has an old test in a drawer should check the date, because a result from two years ago does not satisfy the rule, and a seller with no test at all should decide whether to run one or leave it to the buyer. Our Montgomery County page covers how that rule and the county’s utility bill rule fit into a sale there.

What the disclosure form asks

Outside Montgomery County the law that matters is the disclosure statute, Section 10-702 of the Real Property Article. Before a contract is signed, a seller of a single family house gives the buyer either a disclosure statement answering questions about the house or a disclaimer statement selling it as is. The disclosure form includes a question about hazardous or regulated materials, and radon gas is named in it. The disclaimer avoids the questions, but it does not avoid the duty to disclose latent defects the seller actually knows about that a buyer could not reasonably discover and that pose a threat to health or safety. A radon report with a high number is exactly that kind of knowledge. The safe course is simple. If you have a result, hand it over with the form, and if you had a mitigation system installed, hand over the installer’s paperwork and the post installation test too. Estate sales, foreclosure sales and a few other transfers are exempt from the statute, which is one more reason a sale by a personal representative moves faster, as our probate article explains.

What mitigation actually involves

A radon mitigation system is less than it sounds. A contractor cores a hole in the basement slab, sets a pipe into the gravel beneath it, runs the pipe up through the house or along an exterior wall, and puts an inline fan near the top that pulls air from under the slab and vents it above the roofline. Cracks and the sump pit get sealed. The work takes a day, the fan runs quietly for years, and a follow up test a few days later usually shows the reading well under the action level. Houses on a crawlspace get a plastic membrane and the same fan. The cost varies with the house and the installer, and a retail buyer will nearly always ask you to pay it, either by having the system put in before settlement or by crediting the price. Make sure the installer provides a written guarantee of the post mitigation number, because that paper follows the house to the next sale.

How radon plays out in a retail sale

In a listed sale the radon fight happens inside the inspection contingency. The buyer tests, the number comes back high, and the buyer sends an addendum asking for mitigation at your expense, a credit, or a price cut. You can agree, counter, or refuse and let the buyer walk, and the choice usually comes down to how many other offers you have. Two things tend to surprise sellers. First, once a buyer has tested, the result is now something you know, so if that buyer walks, the next buyer gets the disclosure. Second, lenders generally do not require a radon test, so the demand comes from the buyer and the buyer’s agent, not from underwriting, which means it is negotiable in a way a lender required repair is not. A seller who installs mitigation before listing takes the issue off the table for every showing, at the price of doing the work on a house they are leaving.

Selling with the reading as it is

You do not have to mitigate to sell. We buy houses with high radon readings, with old systems that no longer pull, and with no test at all, across Maryland. In Montgomery County we order and pay for the test the county requires, as the buyer, and the result does not change the written offer. Everywhere else we do not ask for a test, and if you have a report, you simply give it to us with the disclosure form. You send us the address and the basement situation, we look at the house, and you have a written offer within a day with the math shown against a listing. A licensed Maryland title company handles settlement, two to three weeks is typical, and we install mitigation after closing on our own schedule. What else we do not ask you to fix is on our as-is page, and the way the closing numbers compare to a listing is on our costs page.

Check whether the Montgomery County rule applies to your house, give the buyer whatever test result you already have, and decide whether a day of mitigation work is worth doing for a buyer who may still ask for more. If it is not, the house sells with the number in the file and the fan goes in after you are gone.