Load-bearing walls, basement?

[Andreas Blomkvist]

Hello,
Unfortunately, there are no construction drawings, etc., for our house. The only thing the municipality has is some VVS (plumbing) drawings of the basement that I received from them a few years ago.
We're constantly debating whether to stay or move, but the bidding wars in the area we want to move to are crazy right now, so we'll likely stay for another 5-8 years and feel like making some changes in the basement to make better use of it.
I would ideally like to build a garage, but the house's location on the lot doesn't allow for it, so I'm trying to make the best of the situation.

The house consists of a basement, a main floor, and a furnished attic. The house is built with concrete hollow blocks and has concrete floors, constructed in 1951.

I know I'll have to contact a structural engineer, but I thought I'd consult here first and see what you think.

Here's what the basement looks like. The wall circled in blue is load-bearing, and that's the one I would like to remove. Here, there's nothing special, just need to get someone to calculate it and make a building notification. What I'm wondering about is the wall circled in red and the one transverse to it, circled in black. Do you think they can be removed without issues, to create a larger room with a more substantial entrance so bikes, etc., can be brought in without problems?

With these means, the basement garage would become "large" and suddenly really usable.



The main floor looks like this, the blue-marked walls are load-bearing, 30 cm thick. The red wall is half the thickness, could it still be load-bearing? It's the small section circled in black that I would like to remove. That part of the wall is ~20 cm wide, and on each side of it, there are 2 doors. I thought about removing it and building a custom wardrobe there. It's no real problem to fit a small beam there, just a small job, more curious about what you think about it.



Here's what the attic looks like.

 

[justusandersson]

I think you can take down the black-marked wall in the basement. What is it actually made of? If there are no reinforcement drawings or a technical description, it's impossible to make a confident statement about the red wall. There's much to suggest it's not load-bearing, but without technical documentation, you should still treat it as if it were load-bearing. Have you checked if there is a technical description? It was required, and it can often say more than a drawing.

The drawings of the upper floors are realtor drawings (lack dimensions and are not drawn to scale) and are completely unusable for this type of assessment. One might suspect that the red walls are not load-bearing, but it's not possible to say for sure. A more detailed description of the construction method is needed. Make a measurement series that goes across the house, from the outside of one exterior wall to the outside of the opposite exterior wall. Indicate all wall thicknesses and visible materials (not wallpaper). The house may be built with prefabricated parts, and then you'll need to know how before you start sawing.