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Comment by ajross | Hacker News Reader

> Compared to what I'm used to in Europe, California is wasting crazy amounts of energy. Poorly insulated homes, old and inefficient AC/heating units,

Are you living in a particularly new region?

Every time I've seen this come up, the data actually says the opposite: the median US home is better insulated, more recently built and more efficiently climate-controlled. Which is unsurprising, because they're newer, basically. Home technology over the last half century has made huge improvements in energy consumption.

It's true that the median US home is much larger than what you probably see where you are. And obviously that goes to total consumption. But it's not an issue with housing technology at all.

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What fraction of apartment buildings in California have double-pane windows? What fraction of commercial buildings in SF/East Bay have operable windows to take advantage of natural ventilation?

My apartment in SF has operable windows, as do most older buildings I've been in. I don't have an air conditioner, and I rarely use the steam heater thingy (radiator?).

How do you not have an air conditioner? What kind of alien creatures are you in SF? Does the weather there really never get above 80?

Sometimes I think San Francisco doesn't have seasons.

https://www.usclimatedata.com/climate/san-francisco/californ...

Most houses in the bay area do not even have AC, and may turn on the heater for 3 months of the year. It's climate alone is a big household energy saver.

How do they not have AC in the bay area? That seems highly implausible.

Coastal regions tend to have more stable temperatures than inland regions in general due to closer proximity to the ocean (large bodies of water tend to be slow to heat up and slow to cool down). The Bay Area is no exception.

Indeed. The Bay Area is one of the most environmentally friendly areas to live for this reason.

Economist Ed Glazer makes the argument that by not allowing more housing to be built there, more people have to live in more energy consumptive locations (Houston, for example). Housing development policy of the Bay Area has a big environmental impact.

The climate also calls for AC for 3 months of the year if not more. And, compared to Europe, they actually have ACs.

> What fraction of apartment buildings in California have double-pane windows?

One thing that amazed me when moving to California a couple of years ago was reading ads for apartments where the text would gush about the apartment having double glazing!!!1!!

Meanwhile, in Sweden, triple glazing has been the required minimum since the 90s, and older buildings were forced to install a third pane or retrofit new windows or somehow bring it up to code.

These days you can get quadruple glazed windows, but they offer only a very small improvements to triple glazed, so there's not much use.

Sweden is a lot colder than California, it's not surprising that better insulation is required.

Is triple glazing common, standard, or required in any part of the US?

Is double glazing?

Double glazing is common for all new installs. And people will tend to use them for retrofits unless they are trying to cheap out. As for California, it doesn't get cold enough here to pay the premium for triple glazing.

For some years I lived in a rowhouse in the Maryland suburbs of DC, built about 1983. The units there had double glazing. Maryland does not have an especially cold climate.

Where I live now we have single panes, but behind storm windows.

On the other hand, we know a family near Boston who live in a big old house. The husband, a mathematician, calculated that they would never recover the cost of replacing the windows. I don't know how far out he calculated, but I expect it was about 20 years.

Right, so the key is California's housing stock is rather old on average, at least from what I can tell.

That's not correct. California's housing stock falls into something closer to the US median. The oldest housing stock in the US is in the North East and Midwest (which tends to be well insulated for Winter purposes). Those regions saw large waves of high population expansion and housing development previously (50+ years ago), which put down an unsurprisingly large base of housing stock.

California's development by contrast has overwhelmingly occurred in the last 50-60 years (their population has increased four fold since 1950, from ~10m to ~40m today). Compare that to Ohio, which has seen a nearly flat population for coming up on 50 years. New York State's population has only slightly increased in 50 years.

The newest housing stock is in the Idaho/Nevada/Arizona region, Texas and the South East (Florida to North Carolina).

The US generally - and much of California - also aggressively uses air conditioning (central or otherwise) and has for a long time, which has further spurred efforts toward maximizing insulation.

Ok, perhaps it's not exceptionally old. But the point is, while the codes are pretty good now, much of the stock was built decades ago, long before the energy efficiency codes tightened up. When many of the houses in Silicon Valley were put up, attic insulation wasn't even used, period.

I've pulled up a random "YouTube star" "building my dream house in california" video and that looks all the world like a single glazed window, in 2018:

https://youtu.be/OWglKkE-0a8?t=2m17s

It also seems to be a wooden construction.. so frankly I don't know what to think. I'm sorry if this seems like very unconventional evidence but then going from building codes to what people are actually building out there is a whole different story, and then you didn't actually provide any data, either.

Though you are spot on with the ridiculously oversized buildings, like a 3 door garage that is so intimately integrated into the structure you're climate controlling it year round.

California uses a lot of wood because of wood's seismic resistance properties.

modern wooden frame houses with good insulation are very efficient at keeping heat/moisture where it needs to be kept. I am in the process of building new house and recently had same research - build like we used to build house where I am from (eastern europe, brick and mortar) or use something everybody is doing. turned out that this stick frame structure with foam insulation is actually much more efficient.

Attached garages are typically is separated from the rest of the house conditioning space. I do insulation of the garage, but only because I plan to work there. Plus water heater I am installing is actually heat pump, so it should cool garage down a bit.

The wall between the garage and the house is considered an exterior wall, and is insulated the same as the other ones.

Wooden construction does not inhibit insulation. Probably the opposite. It's easier to insulate the voids between studs than it is to insulate a masonry structure. Plus, "stick" building is almost a requirement for seismic reasons in California.

As far as the windows are concerned, I can't tell from the video if they're single glazed or not. Seems crazy to me to do any new construction with those.

Around here, they build a stone wall, then add a layer of insulation against it, then build a brick wall against that.

That layer of insulation had been mandatory since at least mid-80s, and requirements for thickness have increased a few times since.

It's true that they're are houses with low energy labels, but from mid-80s on houses already have a C level - and that's default, with further improvements possible by owners. Currently, minimum allowed label for new buildings is A. But we're already slowly moving to "zero-rated": solar panels supply needed energy (on average, over a year).

Having a stone wall on the inside of the insulated barrier is great for adding thermal mass to the inside. Having all that masonry inside probably helps regulate the temperature nicely. I suspect it's more expensive to do it that way than to use wood studs and batting between them. (Of course it depends on the region you're building in. Wood is cheap in North America, maybe not so much in other parts of the world?)

And because earthquakes are also plentiful in California, we don't want our walls to be too heavy. Tensile strength is more important, as well as flexibility.

Modern framing includes construction with "California corners" for a reason - it allows for more efficient placement of insulation.

The framing techniques used in a modern building are far stronger and more energy efficient than you seem to think.

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