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Comment by bpizzi | Hacker News Reader

> Nobody considers the carbon impact of building a 400sqft / 350mp home today, the lawn, the asphalted driveway, etc. They'll build it, drive a Prius or a Model X, and sleep thinking they save the world one car at a time.

There may be a big difference thought: you build your home once or twice per lifetime (even less if we look at it on a macro POV), whereas you spit C02 in the atmosphere every single day by commuting to work. I won't do the math, but I'd bet the second scenario as a far more CO2 cost that the first one.

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My point was that people literally do not think of the impact of their other actions because all they see around them is "buy an EV to save the climate and show you care".

The average new passenger ICE car puts out ~120g CO2 per Km (a smaller car/engine even less). [0] At EU's 12000Km/year driving average that's <1.5t CO2/year. A house (in the UK but likely representative) is estimated to generate 50-80t of CO2 to be built. [1][2] One can assume that since building a house is already very expensive very few will actively use the even more expensive "greener" materials and construction methods. The lifetime footprint will also be considerable between watering the lawn, heating the house, keeping the lights on, etc. And living in a suburb means you'll pretty much have to use a car because public transport can never efficiently cover spread out neighborhoods of individual houses.

I've read estimates that an ICE generates ~24t CO2 over its lifecycle while an EV generates ~18t. A hefty 25% reduction but still considerable. Yet all you hear is "buy an EV" because manufacturers push for it and people like their status symbol and virtue signaling. Their other actions contradict their purported intention of trying to clean up. The charitable interpretation is that people don't understand how things contribute to pollution and the media coverage of EVs does little to dispel that.

If you want to tackle CO2 emissions one of the best ways is to include the tax in every product and service according to its share of emissions.

*Full disclosure, I drive a small ICE car to the tune of ~0.5t CO2/year. And while this will change soon I am fully aware I am not saving anything but my public image even if my overall carbon footprint is likely way below average.

[0] https://www.eea.europa.eu/highlights/average-co2-emissions-f...

[1] https://www.theguardian.com/environment/green-living-blog/20...

[2] https://citu.co.uk/citu-live/what-is-the-carbon-footprint-of...

The problem with public transportation in suburbs isn't the spread out nature of them so much as the lack of straight lines to run transit on. While it is annoying to wait that long, a bus every 10 minutes can be self supporting in the suburbs, but you can only get that frequency and ridership if everyone rides it and nobody will do that unless it is reasonably fast to get to the destination. The crooked roads in most suburbs mean that the bus is slowly winding around. Not only do cars corner better, but they also spend less time winding because they leave the local neighborhood for a main road which isn't bus friendly.

Don't get me wrong, density is better, but putting the blame on lack of density gives suburbs an excuse they are not worthy of.

Lack of density is the root cause, so it is correct to blame lack of density. There exists no way for public transportation and suburbs to coexist, barring discovery of a zero cost no pollution fuel.

The environmental and economic benefits of public transportation are only unlocked if everyone uses it. If sufficient people have alternatives, such as personal cars, then it weakens political demand for public transportation, as well as economic demand.

And of course, being spread out means spending more fuel per person, which is also not economical.

Lack of density is a negative, but I disagree, it is not a root cause. The old street car suburbs of the early 1900s did just fine then, and as transit systems look at them again they come back. Of course modern suburbs are less dense, but they could still work if the form was correct.

If you take a modern suburb, pack 10 story mixed use buildings on the land and force people to live there. You would have the densest city in the world (remember we forced the population), but transit ridership would still be poor. People would walk most places (unless disabled) because the transit system wouldn't go anywhere you couldn't walk in about the same time. Only by adjusting the road form so you can get someplace in a reasonable amount of time can transit work.

Density is the difference between there always being a bus/train in sight and needing to check the schedule before going anywhere. Having to check the schedule is annoying enough, but a otherwise good reliable transit system can still overcome that.

The UK (and Ireland) have an _extremely_ annoying fetish for concrete block-built houses. I don't understand it, except that perhaps old wooden structures rotted. Or, more likely, it was a consequence of deforesting their islands with overgrazing (the green fields of Ireland are an artificial landscape representing huge destruction of biodiversity).

Talking to the planning officer now and they'll begrudgingly allow timber frame but insist you cover it in plaster, hideous pebble dash, etc., which of course is cement based and carries a large carbon footprint.

If history is any indicator they'll catch up to what the rest of the world is doing and start embracing timber frame homes (which are easier to hit NZEB standards with) about 20 years after everyone else.

Timber frame homes have a much, much, much lower embodied energy footprint, and of course sequester carbon in their wood.

UK insurers and mortgage companies don't like homes of non-traditional construction because they've tended to develop expensive and unpredictable problems a few decades down the line, and they dislike both uncertainty and things that cost them lots of money for obvious reasons.

How is wood housing non-traditional?

It's not how homes have normally been constructed in the UK. We have a few ancient wattle and daub houses which are no doubt hell to insure, but anything Victorian and newer was generally brick-built or concrete other than some prefabs from the inter-war period which are definitely hell to mortgage or insure. Modern timber-based construction methods are completely different from all those things.

Wood is great but it's just one piece of the carbon footprint of a house. It just complements our not-so-green construction materials. Building low and spreading the population of large cities over 1-2 stories tall buildings is how massive swaths of land are no longer green but covered in asphalt, houses, and cars.

Wood burns more easily, it's much easier to damage by water, rot, and all kinds of infestations and pests that are very common in many areas, etc. and on top of that it's very hard to "manufacture". Widespread and extensive use of wood in home construction around the world and deforestation come hand in hand.

Steel, concrete, and brick are still required in volume for any building and to respect safety codes. More so in any dense and seismically active area.

> and of course sequester carbon in their wood.

Trees sequester carbon in their wood, in addition to many other benefits. :)

It took 150 years to come up with usable car batteries. Perhaps in time we'll come up with better building materials that truly sequester carbon either from manufacturing or by actively absorbing it. In the meantime there's no going around the fact that a larger home will have a larger carbon footprint. The average US home has 5 rooms and 170mp/1800sqft plus 300mp/3200sqft yard&all. Moving to timber frames and EVs doesn't compensate for the other choices.

You spit CO2 in the atmosphere every day by heating/cooling the house.

Depends on the performance of the house. Very little 'spitting' if it was built right (e.g. Passivhaus)

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