Radon is an odorless gas that can enter a home from the ground, so you cannot tell whether it is present by sight or smell. A test is the practical way to find out. In Detroit, testing makes sense at several points in homeownership: before or after a purchase, when you change how a space is used, or when an earlier result no longer reflects your home today. Here’s how to choose the right moment.
Before or After Buying
If you’re buying a Detroit home, arrange a radon test as part of your inspection period. A current result gives you information before closing and time to discuss next steps if the reading is elevated. Ask whether the test covers the lowest lived-in level, such as a finished basement, and confirm the testing conditions followed the device or professional’s instructions.
If the seller provides an old result, check when and where it was taken and whether the house has changed since then. A result from another level, a different season, or before major work may not answer your current question. When details are missing, consider testing again rather than treating the paperwork as a guarantee.
After Renovations or Changes
Test after work that changes how you use the lower level. Finishing a basement, adding a bedroom, or turning storage space into a home office means people may spend more time there. Testing helps you understand the air in the space as it is now, rather than relying on a measurement taken before it became part of daily life.
Construction can also change airflow or openings between the house and the ground. If you have remodeled, altered ventilation, or added a new foundation-level space, a fresh test is a sensible check. Follow the test instructions carefully, including guidance about closed windows and exterior doors, so everyday conditions do not undermine the result.
When an Older Result Needs a Check
Radon levels can vary over time, and a past test describes conditions only during that testing period. Retest if you cannot find the report, do not know which floor was tested, or have made changes to the home since the measurement. A new test is also useful when you plan to occupy a basement that was previously unused.
Keep each report with its date, location, test duration, and result. That record helps you compare future measurements and decide when another test is appropriate. If a result is above the EPA action level of 4 picocuries per liter, follow current EPA guidance and consult a qualified radon professional about confirmatory testing or mitigation options.
Choose a Suitable Test
Use a test designed for residential radon and place it on the lowest level where someone regularly spends time. Do not put it in a kitchen, bathroom, or drafty spot unless the instructions specifically allow that location. Short-term tests can provide an initial snapshot; longer-term tests reflect conditions over a more extended period.
For a real estate transaction, a qualified professional can help select and conduct testing that fits the inspection timeline. For any test, follow the device instructions exactly and avoid moving it or disturbing it. If the result is elevated, use an appropriately qualified professional to review the finding and discuss reliable next steps.
Test when a home changes hands, when renovations make a lower level part of everyday life, or when an old result no longer matches current conditions. A properly placed, carefully completed test replaces guesswork with useful information. If you’re unsure which test fits your situation, contact a radon testing professional to discuss your home and timing.