How many windows should one have?

Thanks, that helps, for the moment we will plan some currently planned windows a bit larger and withhold money for possible additional windows that we currently see as a nice option so that we have enough flexibility in the architect discussion.

What additional windows cost also strongly depends on your construction company. In our case, the general contractor calculated walls like windows. Others make a fortune enlarging windows.

No normal builder reads a state building code at the beginning of their research – but only when something in their specific development plan strikes them as odd and they want to know how far the municipality is overshooting the regulation frenzy beyond the standards of the state building code. I advise prospective builders in all federal states except Mallorca, and have never read a state building code without a concrete reason. It’s a reference book, not a novel!

I don’t know why some people here think that we have read the state building code. There were windows in the floor plan, we adapted something there according to our wishes, googled “is there anything to consider about windows” => “yeah the state building code says about 10-15% but that’s old school, rather follow the EU recommendation 20-25%” and based on this result we ask. We have not opened the state building code, nor will we open it.

I would rather call it a distorted view through a warped lens. Not a single provider advertises floor plans with only a minimum number of windows (and as I already said, they are not interested in saving here). Catalogs advertise with competitive models, that applies in all price segments. The "most cited" floor plans are those that are evaluated as attractive and are gladly used as templates for individual planning. A provider who “stingily” provided windows there would cut off their “marketing channel picture platforms.”

As already mentioned, it seems we got a distorted view through our previous conversations with 4-5 construction companies, I specifically pointed out that this could be the case :) Personally, I have already seen several new-build houses that had really few windows that exactly correspond to these floor plans I meant.

You have – at least if you mean the draftsmen/technical sampling helpers of the providers – romantic notions of "architect" conversations. Better show here what you have planned so far – then more concrete tips will come than you prefer ;-)

Thanks for the tip, we will consider it. We still have an “architect conversation” ahead, I can’t yet say exactly who will talk with us, I might ask. Maybe we’ll also post the floor plans here, depends on how much energy we have right now to deal with the forum tone (this is not criticism, just reality, and that’s a good thing).

What additional windows cost also strongly depends on your construction company. With us the general contractor counted walls like windows. Others make a killing enlarging windows

Yeah, regarding that we’re just screwed. We don’t want floor-to-ceiling windows upstairs and must build 1.5 stories with a roof pitch between 40-60° according to the development plan, so we’d have to do a lot with roof windows and the two providers in that sector know about their quasi monopoly, you can invest money intravenously for every square centimeter of window there, not to mention the shutters that cost just as much as the windows. But whining doesn’t help here.

What additional windows cost also heavily depends on your construction company. With us, the general contractor calculated wall and windows the same way. Others make a fortune enlarging windows

For us, the KfW40 wooden window from local production was also price-neutral compared to the wall price. We shuffled things back and forth cheerfully – even the wider patio door (1.20m) didn’t change that.

We started here with a design that was called the "dark dwarf cave." I didn’t really understand that at first, but the more you got into it, the clearer it became what was meant.

After that, I began measuring windows in different rooms and developing a feeling for how the whole thing works. In the office, at my parents' house, at friends’, all the windows in our rental building... Do that! You will be surprised but also get a better frame of reference for "no, too dark, phew too big – the inherited sideboard no longer fits there, too much sun on the TV, ..." You can read standards, but the feeling for how you yourself find it good is still not given by a 1.20×1.50m dimension from some state building code or DIN standard...

We don't want floor-to-ceiling windows upstairs and according to the development plan we have to build 1.5 stories with a roof pitch between 40-60°, so we would have to use mostly roof windows.

If dormers are within the budget, that would be an option for the south side to equip the south rooms with two window sides. Velux offers such duo double window solutions, which we have now ordered. We are in the range of 10k for 2 double windows each 140x66 (so per unit 1.40-1.30) with blinds – but we are also looking forward to the view from the bed into the starry sky...

If dormers are within the budget, that would be an option for the south side to equip the south rooms with two window sides. Velux offers such duo double window solutions, which we have now ordered. We are looking at around 10k for 2 double windows each 140x66 (so per unit 1.40-1.30) with roller shutters - but we are also looking forward to the view from the bed into the starry sky...

Currently, we pay 3.2k for one (WxH) 94x118 Velux window tutti completto (including roller shutters etc), depending on how usable it feels we would go one dimension higher here. Then our doubted "common sense" still has to find out whether we install two of those things in the 19 and 17 m² rooms or not. In general, the price per m² of roof window area does not sound so bad to us, two of our windows would have more area compared to your specifications and cost significantly less (of course, two side-by-side combined ones like yours are probably nice to look at).

A dormer would cost about 15k, without windows.

P.S.: Roof windows that are wider than the rafter spacing do not cost more at our construction company since it is 60cm anyway, so we would have to saw it anyway (statement from the company)

The price I mentioned is the rough list price for everything together with roller shutters and control. Depending on the ranking of your window builder/roofer, you can usually get up to 20% off, which they then variably add back on to you.

What I ordered is called "DUO Lichtband FK08," there you only have 10cm in between. Personally, I find a 10m wide and 5m high roof with two individual 66×118 Velux windows really difficult visually... But appearance is only secondary – first and foremost it's about functionality and practicality.