Radon: Attempt Dos

 

After the radon man left, he told me that the levels of gas that our detector was detecting should drop after a few days due to radon having a half-life of around three days. He also said he would be back in a couple of weeks to place a state certified radon detector/recording device in the basement for a few days to put in our file for auditing purposes.

Well only one of those things really happened.

While the radon did come  back with his detector/recorder and set it up, our levels displayed by our reader never really changed all that much. They might have gone down just a little but not nearly enough as promised. Thinking it might be just a calibration issue since mine was cheap and purchased (probably from China) over the internet and the radon man's recorder probably cost as much as a cheap new vehicle, I hoped it would display different results. 

Three days later he came back to print out the results and pick up his device and while they were slightly less than what I was seeing on our units, it was still a lot higher than promised. The average was just slightly below the EPA recommended limit but I had seen higher values slightly over 200% of that limit. We have also turned off our heat for the most part which helps decrease the values overall. 

So the radon man came back to seal so more cracks on the concrete floor he could get to after I shuffled our storage room all around. We also talked about next steps since neither of us felt that the extra sealing would tip the scales significantly. One of those steps is what the picture above is indicating. What you are looking at is the backside of our downstairs shower. For some reason, whomever built the house didn't bother installing any wall surface so the shower tub/surround is seen. Although we couldn't see with flashlights, we both suspect given the age of the house, that the drain for said tub probably goes through a large rectangular hole cut in the slab concrete to give the plumbers wriggle room in hooking everything up. Holes in the slab are bad when it comes to radon and modern house builders don't leave these holes anymore.

So we talked about sealing that area off from the rest of the house. Since the radon man was busy, I did that work myself which involved cutting up closed cell foam and fitting it around various obstructions in the wall cavity in hopes of tightly sealing everything. I did my best to get the foam tightly fitting but still has small gaps so I bought some caulking and made sure everything was sealed up tightly. For some reason, though I had been looking for clear caulking, I bought black caulking. Since all of that will get covered up further, it wasn't a deal breaker and actually in the dim lighting of my storage room, the black made it easier to do a thorough job.

The radon man is going to drop off a scrap of some radon blocking fabric which he says will seal up everything tightly but needs to be protected with some sort of board from punctures. I just happened to have two scrap sheets that came on either side of my expensive plywood as a protective barrier which I bought for the altar project that fit the bill nicely. Above is one of those pieces cut up and loosely held in place for now. I will do a more permanent job once the radon fabric is in place.

For now, I will continue to monitor our detector to see if that moves the needle any. If our theory is correct, it should move it in a meaningful way. If not, the other alternative is to cut a hole in the wall of the bathroom and stick a pipe through the floor there. This can be done low to the floor and in the corner but will be visible no matter how it is done. This will draw a vacuum beneath the slab on the other side of the footer that divides our house in half and should do a better job at vacating the radon before it gets sucked up through cracks and holes in the concrete. It will also render what I have just done obsolete but this didn't cost me more than a sheet of foam and a couple tubes of caulking. To do the other will require a significant additional expense.