Basement or slab? - Cost estimation

  • Erstellt am 2020-10-12 16:02:30

Thirteen

2020-10-12 16:02:30
  • #1
Hello dear forum,

after a long back and forth, we have finally decided on a little house.
It will be 175 sqm for a family of five.

Now we are still considering: basement or slab foundation?

We have a slightly sloping plot and are debating what would ultimately be the best option. The basement would only be a utility basement, into which a double garage as well as a workshop and storage room are to be integrated.

The alternative would be building on a slab foundation with a double garage plus a storage option/shed.

Since we are building on a slight slope, the consideration is what costs will come with each option. Of course, no one can calculate earthworks, but maybe someone can estimate.
Two earthworks contractors have already looked at the plot, saying that both basement and slab foundation are easily possible. However, no one wants to give us a rough cost estimate. That makes things difficult.

Our thought was that with the basement construction, which includes two garages, we might possibly save some costs for slope support.
Building on a slab foundation plus a double garage plus higher costs for slope support might end up being in a similar price range.
We wouldn’t have much storage space in the house.

We have the following offers:
Slab foundation 17k + 25k double garage including foundation + sum X for earthworks.
Basement 45k + 20k finishing + sum X for earthworks.

Can/may someone give an assessment of which would be the more sensible option?
 

-XIII-

2020-10-12 18:48:54
  • #2
Depending on the equipment, the basement can easily exceed 100000 even without peripheral costs. We are also building a hillside house with a garage in the basement, and just the additional staircase as well as windows and garage doors have cost us 20k. The amount of 65000 + X that you are aiming for is hardly sustainable nowadays.
 

Bookstar

2020-10-12 19:42:45
  • #3
With a slope of over 1 meter, I would build a basement
 

Elokine

2020-10-12 20:13:53
  • #4
How steep is the slope in the building area? In the section of the image, you can only see a number on one line and therefore cannot tell how far apart the contour lines are. Are there any other restrictions in the development plan?
 

Thirteen

2020-10-12 20:45:39
  • #5


Each line represents 1m. That means in the building area it is about 1.5m.

The development plan specifies a maximum ridge height of 11m. So we would have enough space.
 

knalltüte

2020-10-13 19:20:09
  • #6
I consider both totals to be far too low. My nephew has a current offer for a basement of about 120,000, with the ground remaining even on the (sloping) property because the rest of the area can be "simply" filled in. Then of course there are additional costs for retaining structures. No idea what he planned there but 20–40k is not unrealistic. For our approximately 160 sqm slab foundation, we ourselves will probably end up at around 50k including about 250 m³ of soil disposal (in NRW).
 

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