> reality of the situation is that slapping up insulated plasterboard on the inside of half of the UK's homes and putting a trickle vent on the window would sav

> reality of the situation is that slapping up insulated plasterboard on the inside of half of the UK's homes and putting a trickle vent on the window would save an enormous amout of CO2 and make people more comfortable And meanwhile require a complete redoing of all interior finishes, including the finish carpentry, in the home. IMO, that's the real barrier (no pun intended) here. Near Boston, I live in a 1920s structural brick house (I think what the UK would call cavity wall construction). The house was built without any explicit "this material is insulation" and has been retrofitted with attic fiberglass, attic floor cellulose, and I spray foamed one room we renovated. Some of my rooms are painted, which would be manageable cost-wise, but still would have a 20+ year payback period if money had no cost to borrow. Other rooms have intricate wallpaper or decorative wood paneling which would be much more expensive to recreate (pushing the payback period much farther out). With interest rates above 5%, a 20-year-at-0-interest project literally never pays to do. Even grant programs will often cover the direct insulation work but don't (and frankly, probably shouldn't) pay for intricate finish carpentry work or wallcoverings.