I agree absolutely that there are technical solutions to all sorts of insulation problems however as Chris Pearson notes there are other difficulties which affect the cost benefit balance.

You don't have to tell me. In 2010 we bought a stone built Edwardian semi in a conservation area. In the first winter, even though I was only living in it part time, it cost me over £1000 in gas (2011 prices) - really to just keep the chill off it - not heat it properly. If I'd heated it properly full time I reckon I'd have been looking at maybe £3000/year (2011 prices - maybe something in the order of £6000 now).  We've since been through insulating it all properly (i.e. to something close to PassivHouse elemental U values)  - along with triple glazing, ventilation system and so on - and now my monthly DD for gas is £31.70 - so around £380/year (at 2022 prices) - and probably more than a quarter of that is standing charge, and a lot of the remaining usage will be on heating hot tap water rather than space heating. My 1st floor home office has no heating (actually it does have wet underfloor heating, but it's not be set to come on since the day I commissioned it) - and usually it sits at between 19 and 21 degree C - last night (when it got down to -6 outdoors) it did dip down to 18 for a few hours. If I could persuade my other half that keeping all the main rooms at at least 21 degrees wasn't a fundamental requirement, I could probably chop a fair bit more off the bill. There is a small solar thermal panel that helps with the hot water in the summer (with hindsight I would have gone for a larger one), and a log burner that's occasionally used in the winter (which I probably should make more use of), which will help a little too. But all in all I'm pretty happy with the results.

Yes it took a lot of time and work (we did almost all of it DIY, and much of the time I was working near full-time). In my case the house hadn't really been touched since the 1970s so was overdue a major refurbishment anyway. The old lime plaster had well and truly perished, so ceilings and walls had to be stripped back anyway - which made a lot decisions easier. Skirtings, picture rails etc. really aren't a problem, even ornate decorative plasterwork can be replaced (either putting the old back, as I did with the 4' ceiling rose in the front room, or with new (fibrous plaster cornice that's a direct copy of traditional designs is readily available). Sockets and radiators I reckon just need a bit of effort. The difficult one in my mind was interior doors that abut an external wall - the ideal of moving the entire door opening 6" inwards can be problematic - we only had one of those and my other half wanted that wall taking down anyway, so I was excused that particular problem.

In my case the cost of the insulation probably paid for itself years ago - of course it would cost more initially if it had been done by trades rather than DIY and I would have had to count in the extra costs of things like new plasterboard & skim, relocating services and decorating, if we weren't in the position of having to replace them anyway. But still I reckon it can still be very beneficial. One advantage on internal insulation is that it's much easier to do things gradually room-by-room, so spreading the cost and enabling people to do the most used rooms first. Given time trades should get techniques and approaches sorted out to a fine art, so keeping labour costs reasonable.  I reckon the biggest barrier is one of attitude - often the deciding to do it is more challenging than the actual doing - most rooms get redecorated fairly often - while you still need an overall plan to work to - if the norm became 'insulate and redecorate' rather than just 'redecorate' I think we could make a lot of progress in a reasonable timescale.

   - Andy.

An interesting account. Having been bred and reared in the North, I am content with cool rooms, but Mrs P is a tropical animal.

When we entertain for Christmas, the downstairs central heating will have to be full on from breakfast time onwards. The boiler input is 51.7 kW. If it is firing constantly, that will be about £5.67 per hour!

The alternative to Andy's approach is self-build. It has been very interesting seeing the construction of step-daughter's house. It is so well insulated that shall be surprised if they need more than 5 kW to heat their 200 m².

An interesting account. Having been bred and reared in the North, I am content with cool rooms, but Mrs P is a tropical animal.

When we entertain for Christmas, the downstairs central heating will have to be full on from breakfast time onwards. The boiler input is 51.7 kW. If it is firing constantly, that will be about £5.67 per hour!

The alternative to Andy's approach is self-build. It has been very interesting seeing the construction of step-daughter's house. It is so well insulated that shall be surprised if they need more than 5 kW to heat their 200 m².