The EPA and most State Health Departments urge that every home be tested for radon on the first level living area of the home. However they have fallen short in educating people about the importance of testing for radon on upper levels, which can have higher radon levels.
I’ve tested radon in hundreds of homes as a home inspector and radon mitigation contractor. The vast majority of those tests have been conducted in basements or the first floor of the home. On occasion however, I’ve done radon testing on multiple levels of the home simultaneously. Those test results have often shown the highest radon present in the uppermost level.
Many radon testing professionals and most homeowners never test above the first living level in a home. They have no idea if the radon level is higher on the second floor, because the general consensus is that the radon level is highest in the lowest level of the home.
Most professional radon testing is performed on the lowest living level of the home or a basement if present. That is what we are taught to do. In Central New York most radon tests are done in the basement, even if it is not a living area. So it is a common practice in Central New York, and many parts of the United States and Canada that most home inspectors will perform the radon test in the basement level even if it is not a living area, if that basement could be used for any type of activity, such as a workshop or laundry room, etc.
The reason behind this is that, it is is generally understood that radon, being a heavy gas, is highest in the lower level of the home. And I have found that this is generally true most of the time, but far from all the time. Testing for radon in the lowest livable area is a good start, but often testing for radon on upper levels can reveal an even higher radon level in an upper level of the home. Most people don’t realize the radon level can vary a lot from room to room and from one level to the next.
Over the years I have conducted radon tests on multiple levels of homes at the same time with some surprising results. In a newly constructed home a few years ago, we tested the basement, first floor and second floor during the winter, the house was closed up tight and forced air heating system was heating the home. The unfinished basement radon level was slightly above 4 pCi/L, the first floor was lower at just above 2 pCi.L and one of the second floor bedrooms tested at above 8 pCi/L. I have seen similar results in other homes, including my own 1820’s farmhouse which had radon level of 17 pCi/L in the unfinished, stone wall and dirt floor basement; 3 to 5 pCi/L on the first floor and 11 to 13 pCi/L in the upstairs bedrooms.
The type of home construction, the insulation and air sealing of the home, the time or season of year, the type of heating system all play a part in the radon levels in a home and can vary greatly from season to season as well as from floor to floor or even room to room. For these reasons it is not a bad idea to do a little extra testing for radon on upper levels, especially if you live in a high radon area, or have done one test already that indicates elevated radon on a lower level.
Radon is known to be a heavy gas. And not much radon testing has been conducted on upper levels of homes. For these reasons many realtors and radon professionals are not aware that radon can be higher on upper levels of homes so they often tell people that the radon levels are less in the upper levels. Many times that is true but not always. Please understand that the radon level can be significantly higher on an upper floor. Even if the radon level is lower on the first floor than say a basement radon level, it could be higher on the second floor. The only way to know is if you test.
Testing for radon on upper levels is important because for most people the amount of time spent in the home is much greater on the upper levels, especially the level of the bedroom(s). If the radon level is higher on an upper bedroom level it will usually mean greater exposure to high radon levels. Higher radon levels discovered by testing on upper levels may indicate the need for radon mitigation or reducing the radon that was not recommended or realized with prior test(s) at a lower level.
If you have experienced higher radon levels on upper floors in your home, please share your results on testing for radon on upper levels in the comments section below. Thanks for reading.
Our basement is showing radon levels of 17. ( 1 week test) I just started testing our ground level and it’s showing that we are at a 9. It’s only the first day of testing so maybe it is from all the rain we’ve have but I was pretty shocked to find high levels of radon at our floor level. Our home was built in 1908. We have lived here for 12 years so I am concerned about our health now. Hopefully we will show lower levels the longer we test.
That is fairly typical, the first floor radon level, above a basement is typically about half as high as the basement radon level, rough average.
I had a radon mitigation system put in my sump pump due to high levels found in the basement. After this was done I decided to check the rest of the house after the retest in the basement. The rest of the house still wasn’t that bad but it was higher than the results from the basement and the further I went away from the mitigation system the higher it got the end result being my master bedroom was the very worst place in the house.
Now I am trying to ask the people who put the medication system and how I can get the numbers down more in my master bedroom. They are telling me those numbers don’t matter that all that matters is the basement numbers. And yes the level is still low in the bedroom but I have Lyme disease and I am having a very hard time and have not been able to sleep in the bedroom since I’ve moved into the home. So now I am very confused as to what I need to do but something is very wrong in that bedroom I have not been able to sleep in there for the six months I’ve lived here. So I sleep on the floor in the living room.
I would contact another radon mitigation company, the radon level that is most important is the room(s) you spend the most time in. The EPA says the testing should be done on the first level living area. If you do not live in or spend much time in the basement the first floor is where the testing should be done. The radon mitigation system should be able to be modified to address the higher level in bedroom. The EPA says even if the radon level is below 4.0 you may want to consider mitigation if it is above 2 pCi/L in an area where you spend a lot of time.
I have 3.2 to 3.78 radon level on second floor bedroom in a 4000+ sq feet home with finished basement. This is my very first test in past 24 hours of reading.