Exactly, that housing is super desirable by UK standards - probably amoung the most desirable housing in the UK. Pretty much all of those houses will have loft conversions (you can see the loft windows in the roof) made possible in part by removing their hot water tanks.
The reality is that it is actually a bit shit. and would cost tens of thousands to retrofit. The compromises that the owners would have to make in terms of either apperance or internal area make heat pumps very unattractive.
When you're sitting on a property valued at a couple millions, I would have thought investing tens of thousands in it would be fair game. Not pleasant, but acceptable...
Well one thing is there is often a pretty big disconnect between the asset prices of these homes and the incomes of the current owners (these houses have exploded in value over the past 40 years), but setting that aside because you are basically right at least in terms of potential equity:
The main issue is to add insultation you either do exterior insulation which covers up all of the period features that make the property valuable in the first place (and could lead to complaints from neighbours) and for many terrace houses the space between the front of property and the public street is 0, or you give up interior floor space which even at this price point is actually pretty small already. Both lower the value of the home which for most British people is the primary and often only investment (UK financialisation of housing).
The thing is, heat pumps aren't a particularly good deal right now.
Heat pumps generally have less heat output than a gas boiler, so it won't make your house any warmer.
Even taking government subsidies into account, the installation costs are several times higher than a gas boiler, both for the unit and often requiring new radiators and suchlike.
And typical energy prices in the UK might be 6.5p/kWh for gas, 26.0p/kWh for electricity - so even if your heat pump achieves a 3.0 CoP your running costs are still higher. In the UK, the months when you'll want the most heating are the months when domestic solar output will be at its lowest. To make savings you've got to switch to a plan where electricity costs change several times a day, such as https://octopus.energy/smart/cosy-octopus/ and not run your heating between 16:00 - 19:00. This makes a well-insulated home even more important.
And you might think you're going to save money by not paying the gas supply 'standing charge' - but gas suppliers can charge whatever they like to remove your meter. If they say it's £1500 to remove your gas meter and save you 30p/day - you're probably not going to be saving 30p/day
So it's less a case of "investing" in the house, and more a case of "investing" in good karma by helping the environment.
How much heat do you need? We've renovated a row house in the Netherlands - very similar climate - with solid foam insulation and triple glazing. Haven't gotten to installing a heating system yet. Even in the current cold period it's perfectly fine indoors with a cheap hoodie on. If I didn't know it would make the place unsaleable, I'd be tempted to move forward without any room heating system at all, only a small on-demand water heater.
Nice. Who's your supplier and what do you have to do to get those rates? The 6.5p/kWh for gas, 26.0p/kWh for electricity figures are from my Ovo bill for this month.
The reality is that it is actually a bit shit. and would cost tens of thousands to retrofit. The compromises that the owners would have to make in terms of either apperance or internal area make heat pumps very unattractive.