Construction costs are currently skyrocketing

Exactly, and as far as I understand so far, the conversion period for everyone whose heating system is now at least 30 years old is only 2 or 3 years? Considering delivery times and availability of craftsmen, does that basically mean starting immediately?!

That would have to be read in detail again.
Although I think such old boilers were already counted out anyway and possibly only allowed because of grandfathering. There were already regulations in case of defects and change of ownership.

Although there are already differences here. For night storage heaters, you need a thick power cable per heater. That can be retrofitted quite easily. For radiators, you need pipes, which are still feasible. From coal stove to gas heating, everything remains in the high-temperature range. But for heat pumps, you have to go to the low-temperature range, and floor heating is then required. Floor heating is extremely complex since the entire screed has to be removed, plus doors and sockets no longer fit. I now see more ceiling heating there. But for low temperature to get warm, the building envelope must be accordingly upgraded. And that then leads to a chain reaction. On the other hand, you don't want to operate a heat pump with an annual performance factor = 2.

In the era of night storage heaters, houses still had wiring ducts under the plaster or wallpaper. Neither was the cable thick enough to the installation location, nor was the distribution or house connection designed for it.
For the conversion to gas, you needed civil engineering work in the street, civil engineering work to the property and into the house. Then piping for radiators inside the house. This led to ugly surface-mounted installations or interventions in the floor structure.

For a heat pump, you do not necessarily need floor heating. On the one hand, there are low-temperature radiators (yes, these would have to be replaced and yes, they need significantly more space in the room), on the other hand, heat pumps can also be operated in high temperature - at the expense of efficiency. In recent years, a lot has happened again regarding efficiency with heat pumps in general and also in the HT area. By the way, a heat pump with an annual performance factor of 2 (which is very pessimistic) is consumption-competitive with gas, which thanks to LNG will never be as cheap as it used to be, but that is another story. Basically, you are right, insulation comes before system technology. Those who consume little also pay little (and emit little). In my opinion, there should be a regulation that considers insulation measures as a replacement for boiler replacement, e.g., 10 years longer grace period.
Heat pumps can also hang on the ceiling in the form of split air conditioners, which takes 2-3 days' work for a house.

Apart from that, hybrid heating systems also work, i.e., on paper you can fudge the renewable share as you have done for the last 10 years with gas and the two token solar thermal collectors. Similarly, a pellet heating system is possible without touching the radiators or the here suggested "core renovation obligation."

I think you can clearly see from this discussion that Habeck’s confusion will never be approved as he planned. Old buildings must be renovated, certainly! Possibly also with the goal of installing a heat pump (that’s how we do it), but that takes time, money, and must be done with sense and understanding. To me, all of this seems extremely unplanned again, what our green philosopher is putting together there. Let’s see what the traffic light coalition ends up doing with it…

In detail, a post-mortem critique is certainly appropriate. Over such a long period involved here, multiple adjustments will be important as well. Just as in the past.

I once had the topic with my parents. Their house is theoretically designed for storage heaters, but in practice it is heated with two wood stoves. However, they are now in their mid-60s, and making wood and constantly stoking the fire eventually becomes a burden. At the time, my father was quite optimistic about being able to retrofit radiators with little effort and wanted to hide the pipes behind the baseboards. Along with the fiber optic installation, a gas connection was even laid two years ago, which now seems to have been for nothing ;)

I strongly doubt that you can reach 65% with solar thermal. Even with optimistic calculations, it's simply not feasible

I strongly doubt that you can reach 65% with solar thermal. Even with optimistic calculations, it simply doesn't add up

That never works, I want to see the calculation ...

I strongly doubt that you can reach 65% with solar thermal. Even with optimistic calculations, it simply doesn’t add up.

So far, that was the trick to include a renewable share in gas heating systems. Whether it still works with 55/65% will be checked by the manufacturers and possibly implemented in products. I also can’t imagine it. In any case, the solar thermal system would have to be integrated into the heating system; so far, it was sufficient to only support domestic hot water heating. As I said, it was all just label fraud, but it was enough to comply with the laws. People will get creative again. First, the law needs to be in place so that manufacturers can put together their product (packages) in a solution-oriented way. It is by no means the case that the draft entails a “heat pump obligation” or something like that, even if WELT likes to label it like that for their target audience. Simply a lie. I want to emphasize again the split air conditioning variant. Great annual performance factor, relatively easy to retrofit without a “complete renovation,” and lastly subsidized in existing buildings with 30 or 35% through BAFA. Plus the comfort in summer.

I suspect that the 65% figure is more likely achieved with something like a hybrid heat pump (? don’t kill me if the name is wrong), so basically mostly heat pump and something extra to heat during the coldest winter? But that also sounds like an expensive affair.

The scenario "someone bought a house with a 28-year-old heating system during the low-interest phase, financed it to the limit, and now can’t afford the new heating system" honestly sounds very contrived to me. If I buy a house with a 28-year-old heating system, I fully expect that I will have to deal with it soon. And these ideas don’t come out of the blue either. That means either I make sure to renew the heating system quickly now without changing the technology, or I spend more money and switch to something else now. It’s always portrayed as if "completely insulating everything, installing underfloor heating (does the statics even allow that), then you can go for a heat pump" is the only option. If there simply isn’t any money for renovation measures, one is presumably more likely to go for pellets or something (edit: or the above-mentioned split AC). Otherwise, there are quite a few intermediate solutions between "renovate your house completely for 200k and run the heat pump at 30° flow temperature" and "completely unrenovated, annual performance factor <2."

Let's wait and see... I don't believe in a second term where the Greens have a say... Maybe the problem will resolve itself even sooner