Interesting paragraph in many ways. I am a licensed home inspector and find many homes do not have the required slope on the outside grading, 6″/10′-0″. The idea is that water sheds more quickly away from the house keeping the soil more dry that is near the foundation. I wonder if doing this would decrease fungal activity in the ground outside your basement. Do you see moss or algae on the ground? This would decrease water intrusion into your basement. Another source could be fungal activity because of water condensation on the interior surfaces of your masonry basement walls. If that’s the case, you would need to add a dehumidifier to the basement and keep those windows closed (or insulate the exterior surface of your basement walls to keep the masonry warm) This would make the greatest difference when the air is warm and humid and the ground is still cold.

Hi Nan,

Your ups and downs in co2 could be part of our plants photosynthesis daily routine ie takes in co2 during the daylight and at night releases 50% of what it captured earlier that day.

Best wishes

We have noticed on rainy days that the CO2 in the basement shoots up to 1400-1500 ppm. (And we see the pH of the tanks go down.) Based on some internet research I believe the source of the CO2 is microbial activity in the soil. I found an article from a Wisconsin county agent that documented this effect which resulted in the gas water heater pilot light being snuffed out by the high concentration of CO2. As the soil dries out over a couple of days the CO2 returns to the typical level.

We looked into an external ventilation system but there is no way to run an external fresh air source to the basement HVAC due to its location. Well, no REASONABLE way!

Peter, yes, that’s been going around for a while. (HaHaHa!) In fact, I just read that thing about Caesar in an article in yesterday’s New York Times. Here’s the link: Where Does a Candle Go When It Burns?

The difference between the spreadhsheet in this article and the statement about breathing in an atom from Caesar’s last breath is time scale. The spreadsheet is all about what happens over minutes and hours; Caesar’s breath is centuries and millennia.

Thanks, Allison. I assume you, like me, need to save a few pennies before buying that. Appreciate the feedback.

Dave, the Aranet4 and the HOBO MX1102A are both battery powered and portable. David Elfstrom, whose spreadsheet I showed above, likes the Aranet4. My friend Mike MacFarland in California uses the HOBO logger. I haven’t used either yet but am planning to buy the Aranet4 before too long.