Comment by alt227 2 days ago
My house in the UK is 300 years old. It is built of stone with proper ventilation built in everywhere. It never gets damp, never too cold or hot. Air circulates enough to constantly be fresh yet not quick enough to create a draft.
Its a shame homes arent built like that anymore. Looking at how houses like this work really shows how we have created solutions to our own problems in modern home building.
> Stone is an incredibly efficient thermal material which is why animals and humans have lived in caves for thousands of years.
Most stone makes for a pretty bad insulator. But the ground, in aggregate, is a great insulator and has very very large thermal mass. So you can go in a hole that’s more than a few feet underground, and the temperature is fairly constant.
Even then you don't get that sort of quality outside certain economic situations. The proverbial "old house" in california is a stick frame dwelling on a post and pier foundation over a crawlspace.
This is because it seldom rains. So when it does rain the soil is very hard and doesn't absorb much of it. So it comes down the hills and causes landslides and shifting soils in the alluvial valleys that much of californian civilization is built into (since channelized due to said wandering waters destroying early californian civilization multiple times until this was learned and tamed by the u.s. army). And then, of course the earth quakes, which destroyed an early brick structured version of san fransisco almost in its entirety in 1906.
Not to mention available american and canadian lumber connected by railhead to the entire continent. most of such reserves in europe were claimed for sunken ships over the previous centuries. So now you live in a 300 year old stone house probably with a basement instead of a timber building on post and piers because you have no cheap timber to this degree here and you have no earthquake risks or much shifting soil. Could you build a house like yours in the U.S.? Of course, if you pay a premium for it.
Look at passive houses, almost fully airtight, 70%+ reduction in heating requirements, fresh air all day long thanks to hrv
The problem is that people want "cheap" houses, cheap houses coupled with modern regulations = sealed boxes. The average joe doesn't give a shit about building quality, it's all about getting something big and as cheap as possible.
> fresh air all day long thanks to hrv
This costs power and materials. Old houses dont require that. On a global scale, that increases power and manufacturing on a huge scale. Why are we throwing power and more modern materials at a problem that was solved in Roman times?
This would also reduce cost, helping the 'cheap' houses issue.
> On a global scale, that increases power and manufacturing on a huge scale. Why are we throwing power and more modern materials at a problem that was solved in Roman times?
Really?
A high quality modern balanced ventilator can ventilate an average sized house using 20-40W. That can supply over 100cfm and avoid around 90% of the conditioning that those 100cfm would otherwise require.
A good approximation is that 1 cfm at a 1 degree F temperature difference transfers 1.08 BTU/hr (sigh) or 0.317W of “sensible heat”. So, in a mild Mediterranean climate in the winter, heating by 30 degrees F, that 100cfm needs 0.317 times 3000 = 951W of sensible heat added.
So you can burn 951W of fuel. Or you can use 20-40W to get the same amount of fresh air but only need 95W to heat it. Or live in a climate with warm days and cool nights and require less thermal mass and therefore less material to moderate the temperature and avoid the need for active heating or cooling.
Without an HRV, either you don’t heat the building, or you ventilate less, or you use considerably more resources for temperature control.
Oh, and the device itself is two fans, a heat exchanger (fancy piece of plastic, generally), and some electronics and a box. Not exactly resource-intensive to build. And it can usually completely replace your bathroom fans if configured to do so, making it even less resource intensive.
In climates that require dehumidification or winter humidification, it’s more extreme because an ERV can exchange humidity (“recover latent heat”) too.
> Really?
Yes
> ventilate an average sized house using 20-40W
Lets take your conservative estimate of 20w
Quote from Googling: "As of July 1, 2023, there were 145,344,636 housing units in the United States"
145,344,636 x 20w = 2906892720W or 2906.89272MW.
Another quick google says that the average Nuclear power plant outputs 977 MW.
So thats 3 whole nuclear power plants required just to power the hrvs in American homes, using your conservative estimate.
That is without the power required to manufacture, transport, and install 145 million hrvs.
However you phrase it and whatever you say to justify it, thats a huge amount of power required to replace something which nature is quite capable of doing itself.
EDIT: I have just also considered the waste as well. The average HRV has a lifespan of 15 years, so that would be 145 million hrv pumps thrown out and new ones built every 15 years. Thats a massive amount of constant power being used, and mountains of unecessary waste, as well as the power to process that waste etc etc...
What are average high and low temperatures where you live in the UK? I looked up the averages for the UK as a whole (which I’m sure can vary quite a bit once you get more local) but I found between 20C and 2C.
Where I grew up on the shores of Lake Michigan average temperatures average between 32C and -6C. As for extremes, I have personally experienced there highs around 37C and lows down to -28C (still went to work in 3ft of snow).
So I will take my modern home with its ability to be well insulated and heated and cooled.
Yes, people lived there long before those modern conveniences, and they were cold and hot. They kept warm in the winter by keeping fires going inside their dwellings at all times. I even spent a week in autumn living in a recreation of one as a kid. Unsutprisingly, it was cold and everything smelled of smoke by the end of the week. Think of how much smoke and particulate we breathed in to stay warm (and there wasn’t even snow on the ground yet). I didn’t even mind it.
I’ll give the final word though to those living in even colder and more extreme climates, and any intrepid people living above the Arctic Circle.