New single-family house, but for whom?

Hello forum community,

we now have a plot of land and are currently in the planning phase for the construction of a single-family house. We have made a few considerations but are still laypeople in this field. We have already created a floor plan and thus have a rough idea of the appearance. We have already spoken with one or two builders to find out if 1. the floor plan can be implemented as is and 2. if it fits within our budget. Both are fine.

Now, the question for us in advance is whether we should undertake the construction completely through a construction company (with an independent construction supervisor), or if it would be better to have the construction company only build the shell so that it is finished from the outside and we have the interior done by specialists (specifically heating and plumbing).

Is it cheaper (or at least equally expensive but qualitatively better) to plan and have the whole thing installed by a heating engineer and bathroom fitter?

The construction company often works with different heating companies and therefore generally recommends one of these manufacturers. The plan is for an air-to-water heat pump with underfloor heating. The underfloor heating, screed, and tiles would be installed or poured by ourselves. Although the manufacturers are large companies and thus certainly not wrong, it might be the best solution for us as a heating engineer could probably advise us better. The question here, however, is whether the price would go significantly higher.

Furthermore, there is the question of how this relates to a KfW loan (at least KfW55). Do you get the loan only when the KfW is informed that the KfW standard has been met? That would be somewhat contradictory since we have to pay from some funds for installing these standards.

Maybe our approach is completely wrong and you can advise me on a completely different approach to building a house.

Thanks in advance,

Regards, Chrigro

The BU will usually only commission specialist companies. If you feel like it, you can post your floor plan idea here and have it discussed. You will get KFW after you have filled out the KFW application - the house does not have to be standing for this, but the planning does. Don’t be mistaken, this is one of many ways. Be vigilant, don’t save in the wrong place, etc.

Ok, then I don't need to worry about KfW.

Is a BU just as knowledgeable in these areas as an HB? Will he advise me in my interest (energy-wise, price-wise, and technically) on how to install the underfloor heating? To lay it 10 cm or 20 cm apart, or dry or wet? Or will I still speak with a specialist when the planning intensifies?

Here are the floor plans (I hope they make sense):



We want to build without a basement. The staircase is probably not the actual size in the program (here 4m * 1m). Above the front door there should be a window about the same size (I know, cleaning it will be quite an adventure). It will probably be a gable roof, which starts above the living/dining room and is supposed to partially extend over the terrace. There should be no window or chimney integrated into the roof in order to have the largest possible area for the photovoltaic system. The garage (9m long, someday) is to be built on the north side, so a long, narrow window must be installed in the utility room, where the air-water heat pump is also to be integrated. But I still don’t know how to manage that provisionally without a garage.

The north side is at the top.

So my limited experience: the general contractor commissions the tradesman and he does it. If you're unlucky, you get one who has never installed a WP before, so be careful... but you can also have that if you commission and search yourself. He will advise you to go with someone he has had good experiences with - if you get a decent general contractor, it’s not only about the best for his pocket, but also for your house - it doesn’t help him if after the build you tell everyone he only does rubbish - at least if he wants to keep doing this business for a while.
Floor plan is a bit exhausting without dimensions.
I wouldn’t like the master bedroom, on the one hand the door is next to the headboard, on the other hand you have to go through the hallway if you need to get to the toilet at night - or have the flu and the daughter is currently with her friends in the living room. Furthermore, I wouldn’t be sure whether you wouldn’t hear the rattling of the dishwasher while sitting behind the 115 wall.
3 m width for the dining room - depending on the dining table - a bit cramped.
The sofa would be a bit sad for me, no distance, lots of TV ;)
Access to the office questionable!
ABK fits max. one row of cupboards properly.
How are the views?
The bathtub is hopefully just exemplary - although maybe it’s fashionable.

The wall from the bedroom to the kitchen can also be a bit thicker, that's true. The dishwasher might possibly need to be placed somewhere else rather than directly next to the bedroom. The ABK should be 1.80 (60 cm shelves on each side and 60 cm in the corridor). I mismeasured there. Everything else is not a problem for us. In the living room, there is a large wide window at the entrance side, and hopefully enough light will come through the glass dining area from the dining room.

We are still not sure how to realize the hallway on the upper floor. We just want to be able to see the front door from there so that the entrance area feels a bit bigger.

I simply placed the bathtub somewhere where there was space.

Your program has placed the staircase with a length of 350 cm. That will be quite a steep staircase:


However, once the staircase is correctly entered, the layout on the upper floor does not work out. Also consider how the front door opens and who stands where to let guests in.

Information about the knee wall height on the upper floor and marking of the 2m line on the upper floor are missing.

I see the bedroom on the ground floor as [behaelja]. Also the location of the bathroom.

The kitchen will be quite small, at least not much space for tall cabinets/kitchen furniture.

The office on the upper floor cannot really be entered like this, only 60 cm to the staircase.