I live in a moderately cold area and pay less than $2000 a year to heat a ~2000 square foot home. So something that improves the efficiency of the building would have to have a pretty low cost to even pay back at all.

There's probably a few lower cost things that I am overlooking, to the tune of netting out a few hundred dollars of savings after however many years they took to pay back.

> Can be a 20, 30, 40 year payback on insulation. For the builder?

In the UK, houses have energy ratings, which are largely not that useful, but they do allow estimated annual running charge.

The house that I live in we moved in and were spending ~1.7k on gas a year.

We needed to re-render the place, because it has a few missing pieces. we spent the extra £4 to put in 90mm of external wall insulation. We also had to replace the glazing. It was cheaper to get triple glazing (for some reason), however the results of that was that it was 6degrees warmer in winter, and 10 degrees (celcius) cooler in summer. Even with gas prices doubling, we spend about £70 on hotwater and heating.

Maybe a law forcing disclosure of average heating/cooling bills in the listing would do the trick?

That's an appraisal problem. Even cars are valued on more things but they do have mpg plastered everywhere.

You don't even need to go that far, put 100m of tubing 2m underground and plug it in your heat recovery ventilation system, bam free winter freeze protection/pre warming and free summer cooling, all you need is a 30w pumps and you will save hundreds of kw per year

same here. 1940's house with slate roof and vermiculite "insulation". You can't just use modern insulation techniques or blown-in foam because that would make exterior wood rot. You need to keep the air flowing the right way to dry out the wood.

A house built to passive house standards requires less than 10w per sqm of peak heating demand, a 500w toaster will warm 50sqm, which is a decent room already.

There are passive houses built at 2000m altitude in the Alps, some are made of wood and have literal strawbales for insulation, there are no excuses left in 2026 not to build good houses, it's more economical, more practical, more comfortable, more ecological

You could put that 500W into a heatpump.

Passive house standards first gained popularity in Germany and Scandinavia but it seems the principles have been adapted to quite a wide range of climate zones now.

https://en.wikipedia.org/wiki/Passive_house

Take plants that can use enery from the sun 'freely'. Is it cheap for them? Not really when you look at the evolutionary battle between plant species. There is always another plant willing to take your place if you're inefficient, slow growing, not poisoning the ground around you, or some other trick to keep you alive.

Any means to keep energy cheap and abundant must be by force because it is not a natural order.

Not saying it shouldn't, I'm just saying it isn't. Housing should be free and taxes illegal but here we are. Some retard decides to go to war with Iran and it costs 30% more to tank your car, I'm not making the rules. Solar panels got 15% more expensive over night in my country too. What happens when they decide to mess around with China? They make 70% of batteries and panels.

I'm replying to someone who bought a 30kwh battery and 24kwp setup, in my country that's already classified as a "local energy provider" I think they're doing OK financially.

People still spend literal millions on poorly built and poorly insulated mcmansions today btw, it's not a money issue.

GP's argument is the marginal cost when building new is roughly that amount, not that any house can be retrofitted for that amount.

However, it's not that far off for retrofitting, if you do it when your siding already needs to be replaced. Add 3-5" XPS foam to the exterior of any standard house; if a basement you bring insulation several feet down and out below the ground. If cathedral ceiling, when replacing the roof you put 6-8" polyiso down over the sheathing before the new roofing material. If vented roof, get 1.5x code minimum blown in the attic. Air seal first, of course (1-hour of air sealing is the best ROI of anything you can do in an old house).

But nobody wants to put that money up.