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On whether changes in bedroom CO2 levels affect sleep quality

gwern.net

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Re: On whether changes in bedroom CO2 levels affect sleep quality

#261
post #29

I was lucky to get my hands on 5 proper co2 sensors from university, while I was teaching and working. So plenty of test places. What I found: -Just a couple of hours in a office, without ventilation spikes the co2 enough to make everyone dizzy and tired by the end of the day. Keeping eye on the meter and ventilating properly, increased everyones productivity and people werent so tired by the end of the day. - Classr…

do you have recommendations for CO2 sensors?

Re: On whether changes in bedroom CO2 levels affect sleep quality

#262
post #203

Earlier quoted context omitted.

It's unlikely you'll have a noticeable difference in co2 levels with indoor plants, even considering your unusual setup.

I think it’s as simple as biomass produced vs biomass consumed, and I agree a 4x4 garden is not going to fully replace O2 for two sleeping adults. I’ve experimented with building tower setups which would allow 3-5 times the biomass growth in the same space, but it’s a real pain tending to a garden at eye level, and introduces all kinds of new catastrophic failure possibilities when you have water above high power lig…

Nurses used to take plants out of hospital wards overnight because photosynthesis (input CO2 output oxygen) only happens in the daytime, leaving just respiration (input oxygen and output CO2) at night.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#263
post #214

Earlier quoted context omitted.

Most residential forced-air systems don't bring in air from outside (intentionally at least). They recirculate the air in the building through the heating/cooling unit (typically a combination updraft furnace with AC evaporator sitting on top). Modern systems (since late 80s, maybe?) have return air ducts so that you get even heating even if interior doors (e.g. bedroom doors) are closed, but older systems may only h…

Heat recovery ventilators [1] are reasonably common in Canada. Most (all?) EnergyStar homes [2] have one, and they includes most if not all the houses I've looked at (or friends have bought) in the past decade or so. I lived in a house built around 1985 that had one, which was R-2000 [3], so they're at least that old. [1] https://en.m.wikipedia.org/wiki/Heat_recovery_ventilation [2] https://www.nrcan.gc.ca/energy/eff…

Oops, I meant houses that were built in the last ~decade are mostly EnergyStar.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#264
post #29

I was lucky to get my hands on 5 proper co2 sensors from university, while I was teaching and working. So plenty of test places. What I found: -Just a couple of hours in a office, without ventilation spikes the co2 enough to make everyone dizzy and tired by the end of the day. Keeping eye on the meter and ventilating properly, increased everyones productivity and people werent so tired by the end of the day. - Classr…

Wow. Didn't realize how important it was to aerate. I seldom open the windows at my place. I also remember often getting really dizzy working in my previous office, and I couldn't understand why, maybe you're on to something. Now I'm wondering how all of that has affected my health along the years

The recommendation here in Denmark is to air out for ~10 minutes, 3 times a day, ideally with all doors and windows open, making sure to get good airflow between rooms.

I think very few people actually air out that much, but I've found that it's very helpful for my sleep quality to air out just before I go to bed. Airing out in the morning also helps eliminate moisture from showering, as my bathroom doesn't have a window, nor any forced ventilation.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#265
post #29

I was lucky to get my hands on 5 proper co2 sensors from university, while I was teaching and working. So plenty of test places. What I found: -Just a couple of hours in a office, without ventilation spikes the co2 enough to make everyone dizzy and tired by the end of the day. Keeping eye on the meter and ventilating properly, increased everyones productivity and people werent so tired by the end of the day. - Classr…

As someone who has built my fair share of houses and worked on many more over the last 25 years, I have to agree that our ability to seal air better than ever is causing problems, especially if you don't have forced air heating and cooling running all the time. People just completely ignore or haven't ever thought about room ventilation, positive or negative room pressures, and where and how to ventilate to the outsi…

A house should not breathe. A catchy mantra I've run across is "seal tight, ventilate right":

* https://www.youtube.com/watch?v=CIcrXut_EFA

Mold is not a ventilation problem, but rather a moisture control problem. Keep the humidity down (especially with whole house dehumidifiers), and eliminate condensation points (by eliminating thermal bridging), and it goes away.

While the above video, which is from the really good channel by Matt Risinger, is a good introduction, I recommend you also check out the building science stuff put out by Joseph Lstiburek for a more science-y explanation:

* https://en.wikipedia.org/wiki/Joseph_Lstiburek

On the "perfect wall":

* https://buildingscience.com/documents/insights/bsi-001-the-p...

Presentation on control layer (especially starting around 15m):

* https://www.youtube.com/watch?v=rkfAcWpOYAA

Good webinar:

* https://www.youtube.com/watch?v=sBcNFeiWjrg

Re: On whether changes in bedroom CO2 levels affect sleep quality

#266

Earlier quoted context omitted.

As someone who has built my fair share of houses and worked on many more over the last 25 years, I have to agree that our ability to seal air better than ever is causing problems, especially if you don't have forced air heating and cooling running all the time. People just completely ignore or haven't ever thought about room ventilation, positive or negative room pressures, and where and how to ventilate to the outsi…

> As someone who has built my fair share of houses and worked on many more over the last 25 years, I have to agree that our ability to seal air better than ever is causing problems, especially if you don't have forced air heating and cooling running all the time. People just completely ignore or haven't ever thought about room ventilation, positive or negative room pressures, and where and how to ventilate to the out…

You may be interested in the "perfect wall" concept by Joseph Lstiburek:

* https://buildingscience.com/documents/insights/bsi-001-the-p...

Also check out Matt Risinger. They both have various good content on building science.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#267
post #156

Earlier quoted context omitted.

As someone who has built my fair share of houses and worked on many more over the last 25 years, I have to agree that our ability to seal air better than ever is causing problems, especially if you don't have forced air heating and cooling running all the time. People just completely ignore or haven't ever thought about room ventilation, positive or negative room pressures, and where and how to ventilate to the outsi…

Apparently certain residential building codes have air-freshness provisions: I recently added A/C cooling to a previously heat-only house, and I took the opportunity to ask the company to explain some quirks in the existing system, like how the ventilation fan in the laundry room is on the same breaker as the central heating, and had a hidden timer attached to it. The house was built (early 1990s) with a particularly…

See also ANSI/ASHRAE Standard 62.1-2016:

* https://www.ashrae.org/technical-resources/bookstore/standar...

Re: On whether changes in bedroom CO2 levels affect sleep quality

#268

Earlier quoted context omitted.

As someone who has built my fair share of houses and worked on many more over the last 25 years, I have to agree that our ability to seal air better than ever is causing problems, especially if you don't have forced air heating and cooling running all the time. People just completely ignore or haven't ever thought about room ventilation, positive or negative room pressures, and where and how to ventilate to the outsi…

What's the solution? My house is absolutely frigid during the winter, and I got quote for resealing it. He told me that afterwards I am either going to have to leave my windows open (no thanks!) or live with mold. I've heard that you can install vents, but can't find useful info. My grandparents had a chute vent, and it somehow became a breeding ground for flies and all sorts of ichies. Not sure why. And short vents…

Yes. Matt Risinger has a really good channel on building science, and this video is a pretty good intro on air tight houses and ventilation:

* https://www.youtube.com/watch?v=CIcrXut_EFA

Go through the archives as well. Lot's of good stuff.

He's based in Austin, TX, so needs to worry about heat and humidity being kept out, but the principles also apply for colder climate where the cold needs to stay on the outside.

Another good person is Lstiburek, and his concept of the "perfect wall":

* https://buildingscience.com/documents/insights/bsi-001-the-p...

Re: On whether changes in bedroom CO2 levels affect sleep quality

#269

Earlier quoted context omitted.

Assuming the furnace is electric too, they should both be the same efficiency, since 100% of the power is being eventually turned into heat, unless the light from the LEDs are going outside.

I never considered an electric furnace - I come from a land of ice and snow and the only real option is natural gas.

What you want is not an "electric furnace", which uses electrical heating elements, but a heat pump per one of the other replies.

Mitsubishi has some that can extract heat from the outside air even down to -30C.

Most though only work down to about +5C (they're used in more temperate climates). So check the specs.

They also work for AC.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#270

Earlier quoted context omitted.

As someone who has built my fair share of houses and worked on many more over the last 25 years, I have to agree that our ability to seal air better than ever is causing problems, especially if you don't have forced air heating and cooling running all the time. People just completely ignore or haven't ever thought about room ventilation, positive or negative room pressures, and where and how to ventilate to the outsi…

A house should not breathe. A catchy mantra I've run across is "seal tight, ventilate right": * https://www.youtube.com/watch?v=CIcrXut_EFA Mold is not a ventilation problem, but rather a moisture control problem. Keep the humidity down (especially with whole house dehumidifiers), and eliminate condensation points (by eliminating thermal bridging), and it goes away. While the above video, which is from the really goo…

> Mold is not a ventilation problem, but rather a moisture control problem. Keep the humidity down (especially with whole house dehumidifiers), and eliminate condensation points (by eliminating thermal bridging), and it goes away.

This sounds like one of those kinds of answers that only works with spherical cows in a vacuum.

If my shower were completely open and in the middle of the living room, perhaps. Alas, it's in a small private room that usually has the door closed while in use, and now we've circled back around to ventilation...

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