Winter radon testing in Columbus: an October to March plan

Sometime in October the windows close for the season across Central Ohio, and most of them stay closed until spring. That long, sealed-up stretch is the best part of the year to find out what your house is really breathing, and the plan below turns it into a month-by-month checklist.

Why the cold months give the truest reading

Franklin, Delaware, Licking, Fairfield, Madison and Pickaway counties all sit in IECC climate zone 5A, the cold zone, according to the DOE Building America guide to climate regions. Cincinnati's Hamilton County, farther south, is one step milder at 4A. In practical terms, a Columbus house spends a long heating season buttoned up with the furnace cycling.

That long season matters because of the stack effect. Warm indoor air is lighter than the cold air outside, so it rises and escapes through the attic hatch, upstairs light fixtures and every small gap near the top of the house. The air that replaces it has to come in low, and the lowest openings in a building are the ones touching soil: the floor-wall joint, slab cracks, the sump, and pipes that pass through the foundation. The colder the night, the harder that draw. Bath fans, the dryer, kitchen exhaust and fuel-burning appliances pull still more air out of the house and add to the suction on the ground beneath it. Around Columbus the ground itself is often clay-rich glacial till that drains slowly, and wet or frozen topsoil can make the open gravel and loose fill around a basement the easiest path for soil gas to travel.

A closed, heated Columbus house pulls harder on the soil under it than the same house with the windows open in June, which makes a winter result the stricter test and the more honest one. The best season to test FAQ covers the same logic from the testing side.

October: set up before the furnace settles in

• Look at the manometer on any existing radon system. Compare the liquid column to the line marked at start-up. If it has drifted toward even, get the fan looked at before testing season begins.
• Confirm the fan is running. A radon fan is meant to run all year, and a system switched off for the summer is not protecting anyone.
• Find the date of your last test. ODH recommends retesting single-family homes every two years. If your last number is older than that, or it came from a July test with the windows open, this is the season to replace it.
• Decide between short-term and long-term. Ohio's protocol counts anything from 48 hours to 90 days as short-term, so a long-term test runs longer than 90 days. One started in October can cover the heart of the heating season. The short-term versus long-term FAQ weighs the two.
• Book a professional test or order a kit before holiday schedules fill the calendar. See radon testing in Columbus for how a professional test works here.

If you are going to run a long-term test this year, October is the month to put the device out.

November and December: test around wind and the holidays

The holiday stretch brings the habits most likely to spoil a short-term test: fires, humidifiers, travel and a house full of guests.

• Watch the weather. For any test under 96 hours, the Ohio protocol rules out running it through a severe storm or a stretch of sustained 30 mph wind, and late-fall fronts can bring both. Check the forecast for the whole window before you start.
• Leave the fireplace alone during a short test unless it is how the house is actually heated. Ohio's closed-house rules exclude fireplace use for any home where it is not the primary heat.
• Move the winter humidifier. It has to be at least 20 feet from the test device, and so does a dehumidifier, air purifier or ceiling fan. Space heaters need at least 4 feet of clearance.
• Plan around holiday travel. A house left empty during a short test still needs its heat running normally. Ohio's protocol expects a vacant house to be held at about 72 F, give or take 5 degrees, with the HVAC on. Guests coming and going through the front door is normal entry and does not spoil the test.

A thermostat turned way down for a week away produces a number that describes an empty, cold house, not the one you live in. The easiest fix is timing: run short tests on weeks you are home, or let a long-term device ride through the trip.

January: Radon Action Month

EPA marks January as National Radon Action Month, and deep winter is a natural time for a first test in a house that has never had one.

• Order a free kit. ODH directs Ohio homeowners to ohio.radon.com for free test kits, and our free Ohio radon kit guide walks through placement, closed-house conditions and mailing.
• Test the lowest level a person could live on. In a Canal Winchester house with a finished lower level, that is the lower level itself, not the laundry room; in a Worthington split-level, each foundation area gets its own device.
• Test before a spring basement project. If a basement finish is on the calendar for April, a January result tells you whether radon belongs in the budget before drywall goes up.

If you plan to run a single short-term test all year, run it in January, when the house is at its most closed.

February and March: collect, compare and decide

• Retrieve the long-term device that went out in the fall once it has passed the 90-day mark, and send it to the lab as its instructions direct.
• Compare the new result with earlier ones only if they were measured in the same spot. Ohio's protocol places follow-up measurements where the first one sat and never averages readings from different locations.
• Decide. A result under 4 pCi/L means retest in two years or after a renovation. From 4 up to 8, the decision rests on the average of a second short-term test or on a long-term result. At 8 or higher, a second short-term test confirms the number before the decision.
• If the answer is a fix, schedule it in late winter, so the install and the verification test that follows it can both happen while the house is still closed up.

A long-term result that covers the coldest months is a number you can make a real decision on. Late March is the end of the easy window. Once spring arrives and the windows open, closed-house conditions get harder to hold for a short-term test.

If you want a test on the calendar before the holidays, see radon testing in Columbus, or call or text us to pick a date that fits the forecast and your travel plans.