Air heat pump or use gas and solar?

Is it actually correct that in a heating load calculation those basement rooms are also included that are not heated? Even the basement corridor is listed.

We have five rooms in the basement, of which only two are heated. However, all rooms are listed in the heating load calculation, so that it assumes an area of 310.2 m². Is that correct or a mistake?

Whether it is technically correct, I do not know. However, the heating load should be further reduced as a result. Maybe Alex knows that...?

Are both gas/solar and the heat pump actually equally fast at reheating water? With our Nibe F 750, it takes ages for the water to get warm again after we've used it. The fastest is still when it’s below 5° outside, because then the electric heater quickly heats it up. The worst is an outside temperature of over 5 to 10°. You can easily wait around 1.5 to 2 hours. I could well imagine that a gas heater manages to do it faster than a heat pump without the electric heater running, right?

Ultimately a question of the device's performance. If the heat pump has 7kw and the gas boiler 15kw, the latter will probably be faster. But it is also a question of the storage system. Bringing a 400l storage to shower temperature takes longer than an integrated one with 180l volume. I don't know if the heating load calculation is correct. I would have thought only rooms within the heated envelope count: Are the heated rooms insulated against the other rooms? Just ask the author.

I can see in the heating load calculation that the floor plan with the underfloor heating marked is also included. The entire basement with all five rooms including the hallway is marked with underfloor heating. However, only two heated basement rooms were discussed and contractually agreed upon. So I am now quite sure that there is an error here.

Therefore, I cannot commission an energy consultant with the existing heating load calculations, let alone make a decision. I may end up being the fool since the construction might be delayed because the execution planning cannot be completed, but I cannot just say out of the blue which heating system should be chosen..... really annoying.

The basement is either completely in the casing or not at all, right?