Monitoring air quality in your home

[Torquey]

Im wondering if anyone had experience of monitoring the air quality in your house?
Now that the heating is on and windows are mostly closed I find myself with a regular murky headache when spending most of my life indoors (WFH). The wife has mentioned similar and 1 kid likes a good cough through the night.

It got me thinking maybe the air is quite bad in the house and something should be done about it.

Ive seen handheld electronic devices on Amazon between £50-150 but are they really any use? Any other suggestions?

I read something on Facebook (i know!) Where someone had a very small gas leak which was giving them headaches and drowsiness for many months.

[Evanivitch]

First question, do you have a CO alarm?

Secondly, what are you looking to monitor? There's plenty of air purifiers out there that will use a HEPA filter to clean particulates from the air in the house. Which recommend a few different ones.

You would need something different if you were concerned about high CO2 levels, but that's somewhat unlikely.

[nyt]

Carbon dioxide levels can shoot up when windows are closed. You could get a CO2 monitor.
I think that's the most likely thing
https://www.amazon.co.uk/s?k=co2+monitor+indoor&am...


You could also get a Volatile Organic Compounds monitor - perhaps combined with the CO2 monitor.

[Riley Blue]

It happens to us every autumn when the heating goes on. Although we have the bedroom and en-suite windows open throughout the night we still wake up with blocked noses and dry throats. During the warmer months, with no heating on, we're fine.

My entirely unscientific theory is that central heating takes humidity out of the air which rises up the stairwell into our bedroom on the second floor. As we sleep we breathe the warm, dry air which affects our airways causing our coughs.

Every year I think I'll buy a humidifier for our bedroom but never get round to it; perhaps this year I will.

[Torquey]

Thanks all.
I have a carbon monoxide alarm.

To be honest I don't know what I want to monitor. Id just like to know the air inside the house is as close to outside af I can get it.
I'll look into a HEPA filter device and certainly start to monitor co2 as well as humidity.

[Equus]

Riley Blue said:

My entirely unscientific theory is that central heating takes humidity out of the air.

You're near enough that it makes no difference. The entirely scientific bit to support it is that:

The relative humidity in the UK varies through the year, from about 65% in August to about 85% in December, so outside it's actually more humid in winter.

But when you take that external air at 85% humidity (and 5 deg C) in December and warm it up to 20 deg C with your heating system, the relative humidity takes a nosedive ('cos warm air is capable of holding a lot more moisture than cool air).

In the old days of open fires (gas or solid fuel) in rooms, it didn't make such a difference, because a continual supply of external air was being circulated in through airbricks to replace the combustion gases being dumped out via the chimney/flue, and some of the moisture from this would be diffused into the room to boost the relative humidity. From the OP's perspective, this means that it can be worth monitoring the internal and external RH, too.

As nyt says, there's a problem with build up of carbon dioxide and other contaminants and pathogens as well, so it can be a combination of problems, but all stem from the high levels of airtightness in modern homes.

It's one of my big bugbears with modern building standards (PassivHaus in particular), and I think will come to be recognised as a major defect that had a significant effect on health, in years to come.

[Riley Blue]

I've been saying this for over a decade, it's good to know I've been on the right track!

[Mabbs9]

Torquey said:

Thanks all.
I have a carbon monoxide alarm.

To be honest I don't know what I want to monitor. Id just like to know the air inside the house is as close to outside af I can get it.
I'll look into a HEPA filter device and certainly start to monitor co2 as well as humidity.

I think air quality inside can often be better outside. That depends where abouts you live of course. Still air inside allows particulates to settle out so they're less likely to be inhaled.

[Equus]

Mabbs9 said:

I think air quality inside can often be better [than] outside.

In terms of particulates (and especially pollen, of course), that's certainly true; not in terms of oxygen levels, CO2, CO, VOC's and pathogens, though.

It depends what contaminants you're bothered by.

[jimbouk]

Surely in a decent spec new build, the MVHR system will prevent this problem?

[Equus]

jimbouk said:

Surely in a decent spec new build, the MVHR system will prevent this problem?

It helps, but MVHR can't deliver anything like the ACH required for good internal air quality (which is usually quoted as a minimum of 6 ACH) - for the simple reason that to do so, through one or two small registers per room and ductwork of sensibly limited size, generates unacceptable noise levels and uncomfortably localised draughts.

Edited by Equus on Saturday 14th November 12:36