"It is an older house (1925), and the chimney is brick and mortar. However, we were able to inspect it thoroughly both above the roof when we put the cap on and at the attic level before we walled it up, and there was no evidence of moisture on the…"
Since we repaired the floor drain in our basement, the smell of sewer gas has thankfully gone away. But now we have a new, mysterious odor that pops up seemingly without any pattern: what we can only describe as "wet fireplace," like cement and wood…
"Hi, folks! I'm just following up on this post because our problem is now solved! It was the basement floor drain after all. We had the drain replaced, and both the high VOC and high CO2 readings stopped immediately. Thanks to all of you for your…"
"OK, I put the uHoo air quality monitor down by the basement drain, and... immediately its CO2 and VOC readings dropped down to baseline. So the drain is not the source of whatever the heck it is detecting, my wife and I are. But I can smell the…"
"Thanks, Chad! Thanks to your comments and many other helpful ones above, I think I'm going to call a general basement contractor who also does radon work rather than a specialist who only does radon. I think the major leak in our basement may be the…"
"The floor is covered with ceramic tile that is not cracked. The penetration for the water line is well sealed. The only other penetration I'm aware of in the concrete is the floor drain, which is not well sealed and frequently smells of sewer gas…"
"What the mitigation companies around here typically do is drill or dig a hole beside the basement to below the level of the basement floor and depressurize that sump hole with a fan, to try to get the radon out of the ground before it passes through…"
"We only took readings on the one room because we didn't know it was going to be over the limit, and it was a 90 day test. Currently it's only being used an hour or two a week, but ideally it would be more like an hour or two a day, and in any case…"
"Hi, David. I posted a few months ago about how my house tested quite leaky but has high CO2 and VOCs (according to a consumer-grade sensor) when my wife and I are in the house. The house as a whole is leaky and I haven't sealed any leaks yet because…"
Hello again, folks! I just got the radon test back on my new (to me -- built 1925) house, and at 6.5 pCi/L it came in 1.5x higher than the actionable level. The test has an uncertainty of +/- 15%. The test location was a room in the finished…
"As I've said above, I already have plants. They only take in net CO2 when the sun is shining. At night they exhale CO2 just like we do. They may in fact be contributing to the nighttime high CO2 levels in the house."
"I guess the word "quickly" may be misleading. It looks like a precipitous drop on the daily graph, but for example yesterday the CO2 readings went from 1078 ppm when we woke to 911 in under an hour when my wife left the house, but then after I left…"