Radon levels inside a house are not a fixed property of the building. They move. In Davis County a Layton home in midwinter is closed up and heated, and warm air rising…
Radon levels inside a house are not a fixed property of the building. They move. In Davis County a Layton home in midwinter is closed up and heated, and warm air rising and leaving at the top of the house draws replacement air in from the lowest points, including the soil beneath the slab. In summer, with windows open and the furnace idle, the same house behaves differently. Barometric pressure, snow cover, wind, and rain all shift the picture as well. The house has not changed between the two readings. The conditions the measurement was taken under have changed.
This is normal and expected, and it is the main reason two honest tests on the same house can return different numbers. It is also why a single reading is best understood as a snapshot rather than a settled fact. Nothing about the swing means a test was performed badly. It means you should know which question you were asking when you ran it: what is happening right now under these conditions, or what this house averages across a full year. Those are different questions answered by different tools, and the choice between them is yours.
A short-term test sits in place for a short period under closed-house conditions and gives you a quick answer. It is the practical choice when there is a deadline, which is why real estate transactions usually rely on one, with their own rules about timing and about the conditions held during the test. A long-term test stays in the home for a longer stretch, spanning changes in weather and in how the house is run, and therefore better reflects an annual average. Many Layton homeowners run a short-term test first and follow it with a long-term test when the first result is ambiguous.
If you will only ever run one test and no transaction is forcing your hand, a long-term test placed so that it covers part of the heating season gives the most representative picture. If you want an answer sooner than that, run a short-term test and follow the instructions closely, keeping windows and exterior doors closed except for normal entry and leaving the detector undisturbed. The EPA publishes an action level and the Utah Department of Environmental Quality publishes state guidance and maps, so check those before deciding what a particular number means for your household.
Suppose your winter test reads higher than the summer one. That is a common pattern rather than a contradiction, and it does not mean either test was faulty. The useful move is to treat the higher closed-house result as the one describing conditions you live in for a good part of the year in Layton, and to consider a long-term test if you want an average instead of two snapshots. If the two results straddle whatever threshold you are working from, running a longer test will settle the question faster than repeatedly retesting for a few days at a time.
If you decide to mitigate, the seasonal swing stops being yours to manage. Sub-slab depressurization runs continuously and does not care what month it is: a fan draws soil gas from beneath the slab and discharges it above the roofline year round, whatever the weather is doing. The system is re-tested after installation to confirm it worked, and the fan is a piece of equipment that will need replacing eventually, so the indicator on the pipe is worth a glance now and then. To reach contractors working in Layton and elsewhere in Davis County, call 801-644-9000.
If you want a result that reflects how the house sits for much of the year, a test covering part of the heating season under closed-house conditions is more informative. If you need an answer sooner, test now: a short-term test is valid whenever it is run, provided you follow the closed-house instructions. A long-term test spanning both seasons avoids having to choose at all.
Both, most likely. Levels genuinely swing with weather, season, and how a house is operated, so different numbers from different periods are expected rather than evidence of an error. The more representative figure comes from a long-term test, which averages across those changes. If your readings sit on either side of the threshold you are working from, a longer test is the cleanest way to settle what the house actually averages.
Ventilation changes a reading while the windows are open, which is precisely why test protocols call for closed-house conditions. It is not a control strategy, because it depends on the weather and on someone remembering to do it, and it is not practical through a Davis County winter. A mitigation system runs continuously without anyone managing it. Test first, and decide from what the measurement shows under normal living conditions.
Everything begins with a measurement. A contractor places a short-term device for a quick reading or a long-term device for a closer look at your yearly average, then hands you a number you can make a decision from.
Learn more →When a reading sits at or above the action level the EPA publishes, the standard remedy is sub-slab depressurization: a sealed pipe and a fan that draw soil gas from beneath the slab and vent it above the roofline.
Learn more →A sale runs on its own clock. Radon tests during a transaction carry timing rules and closed-house requirements, and it saves friction to settle early who orders the test and who deals with the result.
Learn more →Fans do not run forever, and the little monitor on the pipe is easy to stop noticing. Service means checking that gauge, confirming the fan still pulls, replacing it at end of life, and re-testing to prove the system still works.
Learn more →During a build, the pipe can be run before the drywall closes the walls. A passive rough-in is far simpler than routing a system through a finished house, and adding a fan later is a small job.
Learn more →Test first, then decide. There is no fee to be matched.
Call 801-644-9000County, foundation type, and whether a deadline is involved is enough to start.