ᐅ Window quotes as different as day and night

We also found this site. It really explains a lot about the energy saving regulation. Thank you very much! The difficult part of the project will probably be gathering the various regulations for the change of use—not just the energy saving regulation.

For a change of use, I would recommend finding an experienced local architect. Often, it’s less about regulations and more about political or administrative goodwill. The better the project is prepared and justified, and ideally if the architect has a good connection with the responsible authority, the greater your chances of getting approval without major obstacles.

From personal experience:

Our landscaping contractor owns an inherited farmstead in a rural zone and had started to illegally set up four apartments there. When this was discovered during the construction work, in addition to penalties, he was required to dismantle the apartments. By chance, at a birthday party over the weekend, he mentioned this to a well-established architect, who came up with the brilliant idea to offer the apartments to the city as housing for asylum seekers, on the condition that they would afterward be approved (retrospectively). It worked.

Well, we thought we had it figured out. But so far, his plans are well above the energy saving ordinance, which we don’t understand. I need to talk to him again.

kaho674 schrieb:
But so far his plans are well above the energy saving ordinance requirements, which we don’t understand

As @Dr Hix already mentioned, the requirement of the energy saving ordinance regarding primary energy demand (reference building 2014 without the tightening +40%) does not necessarily have to be met for existing buildings. Only each individual component that is modified must be designed accordingly OR the overall value has to be achieved.

kaho674 schrieb:
after all, 60cm thick walls

60 cm (24 inches) with a brick facade and the windows are hinged on the inside. Have you checked whether the facade is built as a cavity wall with an air gap? It definitely seems likely. Even though blown-in insulation is sometimes debated, you could gain a lot here: cost-effective, preservation of the appearance, no additional reveal insulation needed.

dertill schrieb:

60 cm (24 inches) with a brick veneer, and the windows are hinged on the inside.

No, not at all. This question comes up all the time. No, all the windows are completely dry. We have never had any issues with mold or moisture around the windows.

dertill schrieb:

Have you checked if the wall is a double-skin construction with an air gap? It really sounds like it to me.

The wall is almost certainly solid. We have several holes in the wall where you can see inside, and some sections have already been drilled through – no cavity was ever detected. However, more drillings are planned, and the quality of the bricks will also be determined for the structural integrity.

kaho674 schrieb:
No, not at all. This question comes up all the time. No, the windows are completely dry. We have never had any issues with mold or moisture around the windows.

LOL

Sorry, but that’s too funny

What Till means are what I have already suspected as "window stops." The rough openings for the windows in the masonry are slightly smaller on the outside than on the inside; so the window is installed from the inside against a kind of frame – this frame is called the "stop."

The stop logically covers the window frame from the outside, which reduces the space available for insulation.