How bad does our bedroom air quality get? or how much CO2 do two adult humans produce in a 10x10 closed room overnight? Is it enough to push the CO2 high enough to have an effect?
I've noticed I sleep better when I sleep separately from my wife. I'm the more violent sleeper, so it's not movement related, so I'm wondering if it's air quality related.
Yes, the amount of CO2 each person produces is noticable, especially in such a small room.
If possible, keeping a bedroom window a bit open makes a noticable difference. Avoid closing bedroom door too.
Similarly, if you work from home, make sure to create a draft once in a while.
We got an Aranet4 CO2/humidity/temperature sensor mostly out of curiosity two months ago. Outdoors it's ~430 ppm CO2. 500-1000 ppm indoors is considered okay (according to the defaults), 1000-1400 ppm high, and >1400 ppm bad.
It's amazing how you don't notice how it slowly creeps up to 900-1000 and beyond. Without the device I would notice, except that I'd slowly get tired. I'd probably also drink more coffee. The device helps you see what's going on and how bad it is. Creating a big draft for 5 minutes clears everything out.
Also, you can definitely see from the historical data when one goes to bed in a ~12 m2 bedroom and then an hour or so later the second person goes to bed. Same if one gets up before the other. Definitely good evidence that keeping a window open is a good thing (if you got clean air outside)
I've never been sure how to reconcile this with advice about insulation.
It's currently really cold where I live, and I am trying to limit outside air coming in as much as possible. This then leads to the air having uncomfortably high levels of CO2, as confirmed using an air quality sensor.
Agree. I got a CO2 monitor for my office a few ago and it was a real eye-opener.
It has made me notice "stuffy" air more keenly and helps me avoid it. If I'm stuck in a physical meeting room at work I take lots of walks and breaks. etc.
I haven't tried the CO2 sensor in the bedroom. We like to sleep with fans on and the bedroom door open, which I suspect helps somewhat (depending on how drafty one's house is overall) although is obviously not as effective as having a window open.
Back-of-napkin calculation using really rough estimates:
The average person exhales about 1kg of CO2 per day. That's 542L per day. Let's say you produce 20% of your daily CO2 output during the night, since your metabolism is lower when you're asleep. That would be 108L per person per night, or 216L for two people.
The average American bedroom is around 120-130sqft, or 11-12 square meters. Assuming a height of 8 feet, the total volume of your bedroom is around 25-30KL. Pumping 216L of CO2 into a sealed room of that size will result in a CO2 concentration between 720 and 864ppm. That's not high enough to cause immediate medical problems, but it might have more subtle effects, especially if your bedroom is small or if your metabolism is higher.
Do you account for base CO2 level? Air in an unpopulated beach will be something like 420 ppm; and in my city the outside air is something like 600 ppm, so an empty well-ventilated room is still 680-ish ppm - so if someone starts exhaling, then you'd have to add the 720-864ppm of extra CO2 to that.
Absolutely it does - lots of studies available to show CO2 in enclosed spaces exceeding 1k or even 2k ppm (beyond the level of impairment). Eg a bedroom with two people in ~7 hours or a conference room with 8 people in 1-2 hours.
What is your outdoor air intake solution: Is your home drafty? Do you leave a window open in your bedroom at night? Does it have a fan in it that either pulls air in or pushes air out? Do you have a window open elsewhere in your home that has a fan in it? Does your home HVAC pull air in from outside and pump it into your room? Do you use fan-only recirculate mode?
CO2 measurement gadgets are useful for measuring how stagnant your air is, but the above parcel of questions is a great predictor: if your answers are No for all questions, then you’re probably spiking CO2/humidity uncomfortably high at night.
Changing any of those answers from “No” to “Yes”, in any way that increases the amount of indoor air exhausted outdoors from your bedroom, and/or outdoor air drawn into your bedroom, may help a lot.
Measuring relative CO2 levels using daily graphs from a gadget is an excellent indicator of whether any change had an effect.
I've noticed I sleep better when I sleep separately from my wife. I'm the more violent sleeper, so it's not movement related, so I'm wondering if it's air quality related.