Basement finishers: what to line up before radon month

The second week of December is when a basement company finds out whether the winter is full. Crews are working indoors, the families who booked in October are watching their walls go up, and the next round of buyers is about to spend two weeks of holidays in a house that suddenly feels short of a room. Three weeks from now, EPA opens its yearly National Radon Action Month, and some of the homeowners who test in January will be standing in the very basement they want to finish.

Here is what to have in place before the first of the year.

Radon month is a finisher’s month too

EPA calls radon the leading cause of lung cancer deaths among nonsmokers and puts the toll at about 21,000 lives a year. Every January it runs National Radon Action Month, and together with the Surgeon General it recommends testing every home.

The part that matters for a basement business sits in EPA’s Citizen’s Guide to Radon. It says that before a major renovation, such as converting an unfinished basement into living space, it is especially important to test the area first. It also says to test again once the work is done, because major renovations can change radon levels, and to retest when a family starts living on a lower level.

That gives a finisher three honest places to show up:

• A page on your site explaining why EPA recommends testing before a conversion, what a short-term test involves and when to retest.
• A question in your consult script: has the space been tested? If not, recommend it before the design is final.
• A closeout step, with a reminder to retest once the family is using the room.

What you should not do is promise results or sell fear. If you do not install mitigation systems yourself, say who does, and keep your copy to EPA’s own advice.

Put the egress numbers on your site before the questions arrive

Winter consults keep returning to one question: can the spare room downstairs count as a bedroom? Under the 2021 International Residential Code, which states and counties adopt with their own amendments, the answer depends on the window.

• Every basement bedroom needs its own emergency escape and rescue opening.
• That opening needs at least 5.7 square feet of net clear area, with a clear height of at least 24 inches and a clear width of at least 20 inches.
• The bottom of the opening can sit no more than 44 inches above the floor.
• The well outside needs at least 9 square feet, at least 36 inches of width and projection, and a permanently fixed ladder or steps once it is deeper than 44 inches.

Section R310.7 is the part most homeowners have never heard of. When an existing basement is altered, an escape opening is required for new bedrooms and new accessory dwelling units, not for a family room or a home office. Counties can be stricter. Fairfax County, Virginia, requires an opening in basements of houses built after October 1, 2003, and in every basement bedroom no matter how old the house is.

A page that lays this out for your county, with photos of egress wells your crews have dug, settles the question before the consult and stops a homeowner from budgeting a bedroom without the window it needs.

Show the permit path, because January buyers ask

A family that calls in January wants to know when work can start, and the permit is usually the answer. Fairfax County’s guide to typical finished basement details, revised in July 2024 for the 2021 Virginia Residential Code, is a good model of what to explain:

• A permit is needed to finish a basement at all.
• A basement with a kitchen, a wet bar or a bedroom needs plans submitted to the county and approved.
• Digging a new window well needs a plan submission too.
• Habitable rooms need at least 70 square feet and a ceiling of at least 7 feet, and smoke alarms go in the basement and in each basement bedroom, interconnected and hardwired.

Your county’s list will be different. The point is to publish it in order, with the inspections you schedule and a plain statement of who pulls the permit. A homeowner comparing three finishers after the holidays tends to call the one whose site already answered the timeline.

Book the moisture checks now, before the thaw

No finish survives a wet wall. The model code requires below-grade walls that enclose living space to be dampproofed, and waterproofed where a high water table or other severe soil-water conditions are known. EPA’s mold guidance is blunt about the rest: the key to mold control is moisture control.

Winter is a good time to sell the moisture check and a bad time to skip it, because the March thaw and spring rain show exactly where water gets in. A check booked in January either clears the job for a spring start or turns into waterproofing work first. Either outcome beats a callback in April. Put the moisture step on your site as the first stage of every project, ahead of design.

Spend where the basements are

Basements are a regional product. NAHB’s August analysis of Census data found that 17% of new single-family homes started in 2024 had a basement, but the share reached 67.2% in New England and 62.3% in the West North Central states, while 97.9% of new homes in the West South Central division went on slabs. In our experience the split can also change from one suburb to the next.

Before January budgets go live, check two settings. First, the service area on your Google Business Profile: Google wants it within about two hours’ drive of your base, and drawing it around the towns where basements exist wastes less money than a plain radius. Second, your primary category. Whitespark’s latest Local Search Ranking Factors survey, published in November, ranks the primary category as the top factor for the map pack, so a profile filed under a generic remodeling category gives away searches that say “basement”.

What to do this month

• Publish or update a radon page that cites EPA’s advice to test before a conversion and retest after, and add the question to your consult script.
• Put up an egress page with the code minimums, your county’s amendments and photos of wells you have dug.
• Write out your permit steps in order, including which projects need plan approval in your county.
• Open January and February dates for moisture checks so spring starts are not held up by a wet wall.
• Check your profile’s primary category and service area against where basements actually are.
• Ask every family whose basement you finish before Christmas for a review while the room still feels new.

For a few weeks each winter, a federal agency spends its own money telling homeowners to go downstairs and pay attention to the basement. The finishers whose radon, egress and permit answers are already online are the ones those homeowners call. Our page on marketing for basement finishing contractors sets out the full year, and our local SEO work covers the profile and service area settings above.