We had our house tested for radon when we moved in in the fall of 2014. It tested very low, but I was wondering if I should have it tested again just to make sure. How often should I have it tested? I am also wondering if one of those home tests that you send in is OK, or if I need to have it professionally tested.
Depends on many factors. Do you spend a lot of time in the basement? What were the environmental conditions when you tested the first time? Was it spring when everything is wet? Winter when the house is closed up? Seasonal variations can influence radon levels a fair bit.
We had our house tested before we purchased and it came back high so we required the sellers to install a unit. Our basement is unfinished and it's unlikely we'll get around to ever finishing it. Plus, we only go down there to get something from storage and to do laundry. So, in hindsight, we could've used that $750 the sellers paid toward something else.
Regarding frequency of testing...if you spend a lot of time down there, I would consider getting it tested every 3-5 years (this is my guess, not a professional opinion). If yours tested very low and remained low after 3-5 years, I wouldn't be too worried about it. If it was something I was concerned about, I would go the professional testing route. You'd spend on the order of a couple hundred dollars every few years, so the cost shouldn't be too much to bear. A proper radon test will evaluate levels over an extended period of time, not just a few days like the store-bought tests. I'm sure the store bought tests are fine, but I would venture to guess that their accuracy is highly variable based upon things like when/where you place the applicator.
