Of course, mechanical ventilation and heat recovery helps. I had it in my last place which was a new build. But now you're saying on top of the wall insulation

Of course, mechanical ventilation and heat recovery helps. I had it in my last place which was a new build. But now you're saying on top of the wall insulation and heat pump, I also have to spend £10k on a MVHR system? My heating bill is only around £1200/yr - I'll never see that all money back even if it reduced my costs to nothing. The reason costs are high is partially because costs have gone up a lot lately, and I'm in London. Even a new garden fence is going to cost me around £5k. But also, my house would need to have a brick cladding put on after the insulation to get it past planning. There would also be a lot of remedial work required before installing the insulation, such as removing the existing pebbledash render. And I don't even have asbestos to worry about (as far as I know), unlike a lot of other properties of similar age. I agree we're a long way off net zero, but don't you think spending all this money on marginal improvements to old houses would be better spent on the generation side of things? Personally I can't see a future in the UK that doesn't involve some kind of hydrogen or synthetic natgas generation. We're going to need to solve the generation side anyway. I had district heating which I had in my last place, which was great and had the footprint and plumbing was comparable to that of a regular gas boiler.