Initial questions about the prefabricated house, garage, underground garage, KFW

Hello house-building community,

During the house search, I have now also discovered appealing plots and have been looking into prefabricated houses. To roughly analyze feasibility, I have a few questions. A solidly built house would not be an option, as the costs would be too high and the initial occupancy would take many months, with the double burden simply being too much. Whether it becomes a prefabricated house or a house to be completed later is still up in the air. Perhaps most likely something where the sanitary installations are already done, but no floors, wallpaper, etc. Yet now to my questions.

I already have very specific wishes. Namely, I would like (Option1) next to the (prefabricated) house a double garage that is higher than usual. I would like a small 4-post lift in it to park a rarely used car and also for repairs. Between the garage and the house, there would be a passage to the garden. Now to the question: Can you assemble a prefabricated house so that you can use a balcony over the garage on the upper floor?

Option 2 (favorite) would be an underground garage for at least 2 cars under the prefabricated house. Additionally, 1-2 basement rooms would of course be advantageous. If you calculate about 30,000 for a basement, how much more expensive would this option with an underground garage be roughly? The perfect thing would be if you could also build a pit at one parking space for repair purposes on the car.

Then I have questions about KFW.

Is it true that, for example, with a KFW55 house you get a loan of 50,000 at about 1.5% interest PLUS a repayment subsidy of 5%? That means you get 2,500 on top? Many prefabricated houses have no information about KFW. Is this not offered?

What additional costs come with house construction? Floor slabs are probably not included in the house price. A basement is a MUST for us. I estimate earthworks at about 5,000. How high are the costs for setting up the construction site and laying the electricity and water/sewage lines? What other costs are there? The assumption is a single-family house with a rough footprint of 10mx10m.

Best regards Tobias

Hello Tobias,

You are making it a bit too easy for yourself. Please read up here in the forum, as the majority of your questions have already been "discussed" here very often. Thanks

A properly solidly built house would not be an option, as the costs would be too high here and the initial occupation would take many months, and the double burden would simply be too high.

That is – with all due respect – nonsense. Even a prefabricated house does not stand from one day to the next after you have signed the contract. Often – with lead time – it takes considerably longer until the key turns in the lock for the builder.

Option 2 (favorite) would be an underground garage for at least 2 cars under the prefabricated house. Additionally, of course, 1-2 cellar rooms would be an advantage. If you calculate about EUR 30,000 for a cellar. How much more expensive would this option with underground garage roughly be? It would be perfect if a pit for repair purposes on the car could be built at one parking space.

EUR 30k for a cellar – but that would certainly only be a partial cellar.

With a floor area of 10 x 10 you are already at about EUR 40/45k for a usable cellar. For an underground garage, a further good EUR 20k for the necessary soundproofing, sealing from the living areas and ventilation system will be added. Another 3.00 m deeper for a pit will certainly call for another EUR 10k. All approximate price indications assume exclusively good soil conditions; if the soil surveyor has a surprise for you, up to EUR 10k or more can be added.

Which additional costs occur for the house construction? ... What other costs are there? The assumption is a single-family house with roughly 10mx10m floor area.

https://www.hausbau-forum.de/ratgeber/bauherrenhilfe.422/bauherrenhilfe-vor-vertragsabschluss.424/bausumme.662/#Baunebenkosten%20und%20Grunderwerbsteuer

Rhenish regards

A properly solidly built house would not be an option because the costs would be too high and the first occupancy would take many months, and the double burden would simply be too high.

That is a widespread misconception. Although the house itself is erected in a few days, the construction of the house in the factory still takes quite some time.
A prefabricated house provider told us last year in October that the capacities in his company were so fully booked that we could expect the house erection only this October...

Whether it will be a prefabricated house or a shell house is still up in the air. Perhaps something at best where the sanitary installations are already done, but still no floors, wallpaper, etc.

That somewhat contradicts your above statements. With a shell house – most prefabricated house manufacturers offer different stages of completion – you would have to reckon with a lot of own work, whereby the double burden would also apply during this time. In my opinion, such a thing only pays off if you currently pay little or no rent and can build out "at your leisure," that is, without financial pressure.

Option 2 (favorite) would be an underground garage for at least 2 cars under the prefabricated house. Additionally, of course, 1-2 basement rooms would be an advantage. If you calculate about 30,000,- for a basement, how much more expensive would this option with an underground garage roughly be? Perfect would be the case if you could also build a pit at a parking space for car repair purposes.

A basement, the excavation, and possibly transportation to a landfill cost a lot! For a purely utility basement of 10.64 * 9.84 we would have paid around €40,000 (WU basement). Excavation and transportation were not included in this price. You can calculate another €10-15k for that.
However, this would have been within the thermal envelope of our house and thus relatively uncomplicated to construct.

Your idea of a garage under the house involves further planning (garage within the thermal envelope, how about exhaust gases, etc.), so this will probably be very expensive for you.
It is certainly doable with a prefabricated house manufacturer as well. You might have to get an external basement builder.

Then I still have questions about KFW.

Is it true that with, for example, a KFW55 house you get a loan of €50,000 at about 1.5% interest PLUS a repayment bonus of 5%? That is, you get €2,500 extra?

Correct.

Many prefabricated houses have no information regarding KFW. Is this not offered?

Of course! Our house will be a KfW70 house, but we could have had KfW55 as well.

What construction costs still come on top? Floor slabs are probably not included in the house price. A basement is a MUST for us. I calculate excavation work of about €5,000. How high are the costs for setting up the construction site and laying the electricity and water/sewage lines? What other costs are there? The assumption is a single-family house with roughly 10m x 10m floor area.

Best regards, Tobias

You can count on additional ancillary construction costs of €35,000 - 40,000 (without floor slab or basement).

Best regards
Jaydee

next to the (prefabricated) house a double garage, which is higher than usual. And I would like to have a small 4-column lift inside it *** Option 2 (favorite) would be an underground garage for at least 2 cars under the prefabricated house

.. and as an addition from me to the above answers .... you first have to find such a building plot that allows something like this in the development plan ... maybe you will find one in a mixed-use or industrial area ..

.... Then I still have questions about KFW.

Is it true that for a KFW55 house, for example, you get a loan of 50,000,- at about 1.5% interest PLUS a repayment grant of 5%? That means you get 2,500,- extra? Many prefab houses have no information about KFW. Is this not offered?

What other costs are added to house construction? Concrete slabs are probably not included in the house price. A basement is a MUST for us. I estimate earthworks of about 5,000,-. How high are the costs for setting up the construction site and laying the electricity and water/sewage lines? What other costs are there? Assumption is a single-family house with roughly 10mx10m ground area.

Best regards, Tobias

The building expert already mentioned the ancillary building costs. They come in any case.

Basement, you have too low expectations.

For earthworks, any amount between €5,000 and €50,000 is possible, since it depends solely on your plot and what needs to be done.

Regarding KFW, yes, there are definitely KFW 55 or better prefab houses. I have one. However, this usually means extra costs that you have to be able to afford. You then get a credit of €2,500 from KfW if proof is provided that everything fits. However, you do not get this paid out, but only offset against your loan. However, as already mentioned, the extra costs are somewhat higher than €2,500 to go from KfW 70 to KFW 55.

We had to wait 11 months for our prefab house to be assembled, then another 3 months until we could move in.