The trend in Seattle at least is to take one SFH policy and build three town homes on it that don’t share walls but have the minimum buffers between them and the property line. People don’t really build homes at all, developers do, and they want to maximize the earnings they can get on an expensive plot of land.

Fwiw, that's my non-American impression of North American suburban homes everywhere (as far as I've seen, largely TV/film of course) - y'all say scathing things about terraced houses in Europe, but then your own seem for the most part detached only as a technicality.

(And probably it is mostly about making legal and construction matters easier? No party wall; if you want to tear it down and put a new one up you can do so without disturbing the neighbours' property, etc.)

We have townhomes that share walls as well. My wife wasn’t a fan although I loved one place like that. It’s mostly preference going on.

I know, it just seems like preference is much stronger against them / there are fewer of them in NA. Maybe because if you build your houses with a timber frame you need an air gap not to heat the neighbours? Also I suppose the cost saving of constructing like that is a lot less than with brick or even breeze blocks.

I would say 25% of the townhomes here in Ballard are row homes that share walls, the rest are townhomes with footpath sized spacing between them. It isn’t a matter of heat here in Seattle, heat pumps are efficient and insulation between homes is pretty good.

Besides cost savings, you can fit more in if you don’t have those foot paths between, but the market isn’t into it.

Sorry, 'heat' was a typo for 'hear' - air gap not to hear the neighbours, I wasn't worrying about cheap neighbours sapping up your heat, ha. (Although anecdotally, that can be huge for mid-storey flat/apartments, not completely stupid.)

In Southern China, flats built as early as just 10 years ago lack indoor heating and reasonable insulation. So even if you want to heat your apartment with a space heater, you aren’t going to get very far. The coldest 5C I ever experienced.

Noise is an issue. In particular the one I really wanted to buy overlooking the Ballard locks, we suspected that the unit next to us was a party airBnB.

If a home does not have a shared wall, it is not a townhome.

There regional variations in how the word is used. In my region, a townhome is defined via other criteria.

People building their own homes are outliers.

Most homes are built by cookie-cutter block developments, and they make the most money by:

1. Minimizing the size of their lots.

2. Maximizing the size of the homes on the lots.

They subdivide as much as they are allowed to, and build as big as they are allowed to. If the houses in your city are too big, it's because the smallest allowed lot size is.

If we ever caught up with the housing shortage, and there was a glut of housing on the market, maybe developers would start to build smaller, but we aren't there, and we won't be there for the next ~30 years.

If there was a glut of housing developers would quickly exist the business or go bankrupt. It’s either feast or famine for them, and the 2008 crash is why it took so long to ramp back up a decade later (talent pipeline for people who build homes stalled big time).

Again: I know builders.

The size of the home is not a structural rule of the building industry, and is not universal or permanent. Just like any business, it's something builders decide based on who their market is and what they think they'll buy.

The described strategy might be what you're seeing in your area and might be the only thing that makes sense to your own tastes, but there are plenty of cities and counties where the pressing demand from buyers is for other things. In trend-leading communities, demand has been growing for years for denser housing with immediate access to retail and commerce; for efficient homes with low utility costs or green considerations; for small houses, condos, and townhouses that are well-appointed but accessibly priced and low-maintenance, etc and this is what builders have been building when they've been able to get cleared to build at all.

Builders build bespoke one off things for crazy people. Developers build bulk housing to try and make a profit, and they maximize FAR.

The options are not limited to {"bespoke custom house", "one size for all"}.

These ones from this builder vary from 80-320 square metres (~10 square feet per square meter): https://www.heinzvonheiden.de/hausfinder

It would be hilarious if the famously choice-filled capitalist USA has a building industry limited to Cold War DDR "commie block" identikit construction.

In the US, price per square foot is an important metric for appraisal. If the appraiser puts too low a price on the house, the buyer can't get a loan. Therefore if you are building in the US to sell the house, then you will maximize the square feet to maximize the appraised value.

In addition, it is relatively rare in the US for an individual owner to commission a custom house to be built. Particularly in the more populated areas, it is more overhead to build one house vs several houses, so people buying new houses are typically buying a new house in a development with mostly cosmetic differences as their only choices.

The number of buyers able to obtain a loan increases if the home’s price is lower.

Increasing a home’s price reduces the number of potential buyers.

The reason to build a more expensive home is to be able to sell for a higher price. But if the population of buyers in a location cannot afford to pay more, then a builder would be stupid to build the most expensive home they can, because insufficient people will be able to afford it. Hence smaller (cheaper) homes get built in some places, and bigger homes in other places.

Exactly, and there is plenty of unmet demand from people who can afford high prices. It makes sense to build the most profitable thing you can sell.

> In the US, price per square foot is an important metric for appraisal. If the appraiser puts too low a price on the house, the buyer can't get a loan. Therefore if you are building in the US to sell the house, then you will maximize the square feet to maximize the appraised value.

Something in that paragraph doesn't add up. 500 sqft/$500k property is $1k/sqft, a 750 sqft property needs to be valued at at least $750k to be the same price per unit area; bigger is not sufficient for more per unit area — my expectation would be that cost is sublinear with area for most residential units due to various fixed costs such as (an assumption on my part) utility connection fees and architecture fees.

Mid scale development, entire districts at a time, I'd expect that to be linear with regard to area (so the derivative, cost per square foot, is constant); Very large scale, an entire city at once, that I'd expect the derivative of cost with respect to area to increase as size increases, due to the expectation that infrastructure becomes a dominant cost.

On a national level, the trends are that home size is increasing and lot size is decreasing. Sure there will be some local variances, and it is driven by what the market will support, but it's still the general trend.

In my view, it's also the aspect ratio of the lots. Most suburban lots are fairly close to square. That leaves wide side yards that are just wasted space. Who ever really does anything in their side yard?

Lots should be narrower. You could get more houses on a block, and they'd could all still have a usable front and back yard. In fact I'd allow them to be built closer to the street, because nobody really uses their front yard either. A nice backyard is something most people would use and enjoy.

Wide side yards are moats to keep you away from your neighbors. This is widely seen as a feature, not a bug.

"Not meeting your neighbors" works even better in a high rise, and that is tightly packed. :)

Not really, when you can hear every breath they take through the walls.

For noise reasons and to prevent spread of fire

That’s basically what you do with town homes. You need to obey minimum setbacks for fire reasons, but otherwise no yards.

Front gardens are a benefit to everyone in the neighbourhood, maintained at cost to the owner. They are an anti-SUV, in a way.

I could even support tax benefits for maintaining green space in the public view. The alternative (I saw this the UK) is that people turn their front garden into parking or expand their building towards the street.

Grassy front yards are a complete waste of space and water. Kids don't play on them. The person who uses a front yard to grow food is pretty rare.

At the end of the day, too, we have a housing crisis, not a front-yard crisis.

Lawns are bad but greenery is good.

We can recognize the need to not recreate Kowloon in the context of a housing shortage.

It's more likely that a man will jump to the moon than a North American municipality is to recreate a Kowloon.

"Who would want to heat all that" is very much dependent on the available energy subsidies.

I lived in a 3x2.5 meter room one time. There are obvious drawbacks but it had a surprising amount of advantages too. Using all available space leaves very little air to heat. Where would you get oxygen in a normal house? It's not like my heater can keep up if I open the windows.

3500sf houses (my home is not a McMansion) are not likely to become unfashionable. They sell for insane amounts of money because they are so desirable - even old ones and all the maintenance issues that come along with them. We should be meeting the demand of what people want.

> preferred home size is just a fashion

It's been a linear and monotonic increase for over 100 years