Comparison of construction performance description! What should we prefer?

Hello!

I have really read a lot here already, unfortunately many write with abbreviations like e.g. WU-Keller or something... I can't really tell what is meant. But that's not the only thing.

The starting situation is, we want a basement. We have a hillside location, the street is at 0m, the building window starts at -1.5m and ends at about -2.7m. We want partially a granny flat, about 1/3 of the total dimensions... about 35m²! The rest of the basement shall not be living space and should also be completely underground.

The fact is that we own a building plot and we don't know with whom we will build, since a comparison is not really possible. One construction company writes in their construction and service description, strip foundation and steel fiber concrete, exterior walls poured concrete... the others write, floor slab reinforced concrete with 15 kg/m² steel content or something and masonry with bricks (hollow bricks).

Since there are semi-detached houses (from the 60s) in the neighborhood, I have looked at these more closely. Some have cracks in the basement exterior walls. Now I don't know which type of basement, meaning in terms of building materials, we should choose.

Thank you in advance for your experiences and suggestions!

Hello kochones,

regarding the topic of cellar construction with unclear soil conditions:

I would definitely recommend a soil survey to you. Many companies no longer even build without this survey. In my opinion, it is definitely money well spent.

The issue of comparability of construction service descriptions also occupied us a lot.

In the end, we created an Excel table in which we entered the contents (sorted by trade) of the construction companies under consideration.

In doing so, we found that companies with similar scopes of services are also quite similar in price – many "Billigheimer" are even more expensive than the initially more expensive providers, despite having the same scope of services...

Regards,

Dirk

Hi kochones, as soon as you know what you want, you can easily compare the offers. So first find out what you need. The only way to do that is by asking and reading. For example, we also learned a lot about materials, suitability, and the like at trade fairs and similar events.

Yes, thanks first of all!!

@doc.schnaggels: Topic: Soil survey, most builders or developers or general agents already offer it. I don’t know if ordering a surveyor will be considered as our own contribution. But good tip, I’ll ask about that right away. But that’s where our problem as laymen also starts, let’s say the soil survey shows seepage or pressing water. What does that mean then? That we definitely need a poured concrete basement and also strip foundations? Or is a brick basement with drainage sufficient? As a layman, unfortunately I cannot assess whether one is better than the other.

Therefore my question to you pros: In case of a bad soil survey (i.e. seepage or pressing water) is strip foundation with steel fiber concrete and poured concrete basement walls better than a basement with brick floor slab?

@michalko: We haven’t been to an architect yet because we are afraid of the costs. Maybe you can take that fear away?! What does it cost, roughly, for such a planning and the tendering?

@kaho674: Exactly that is the problem as a layman....you are simply told that this will be installed, it’s good and done. Whether there will be settlement cracks or similar afterwards....only very few think about that.

oh man.......why didn’t I just learn to be a bricklayer?

A soil report states how the basement must be constructed to be waterproof.

A soil report states how the basement must be constructed to make it waterproof.

Oh, I see! Thanks for the info! I thought it only stated what the soil conditions are like there!