ᐅ Is the foundation slab properly sized?

Hello everyone,

I wish you a Merry Christmas and have a question right away.

We started building this month. It’s a single-family house with a concrete slab foundation and a garage, which we are having constructed by a local general contractor.

The concrete slab was poured on Thursday, and we inspected it today.

I’m wondering if there might be a mistake because I interpret the plans differently.

Maybe I’m completely wrong with my amateur observations, and I will speak with the general contractor in the new year. But at the moment, I’m pondering it, and maybe you can help put my concerns to rest.

Here’s the situation:
Our solid brick house is being built using a cavity wall construction and will be plastered on the outside (wall structure from inside to outside: 17.5cm (7 inches) Poroton brick, 18cm (7 inches) mineral wool insulation, 11.5cm (4.5 inches) Poroton brick). On the street side, the garage is set back by 25cm (10 inches).

However, the garage’s concrete slab extends slightly further forward than the house’s slab. To me, it looks like the slab is aligned with the load-bearing walls. That would make sense, but the facing wall also has to be built on the slab and cannot be “floating” in the air, right?!

Am I missing something here?

I’ve attached a drawing and a photo of the construction.

I’m very curious to hear your opinions.

By the way, our general contractor is responsible for the shell construction and the foundation slab.

Thank you ✌️

Is the drawing part of the construction documents or just a rough sketch?
So far, I agree with you that either the setback is missing or the wrong material has been planned. In any case, I would ask for clarification.

That would probably only be the case if the outer shell is not supposed to rest on this slab. The drainage pipe within the slab might be an indication of that.

How did you arrive at this rather unusual wall construction?

K a t j a schrieb:

Is the drawing part of the construction documents or just a sketch?
So far, I agree with you that either the setback is missing or the wrong material has been planned. In any case, I would ask for clarification.

This is the official floor plan on which the construction is based. So the final result should definitely match. I will definitely ask for clarification, let’s see. Thanks for your input.

guckuck2 schrieb:

That would probably only work if the outer layer is not supported by this slab. The drainage pipe in the slab could be an indication of that.

How did you come up with this rather unusual wall construction?

What exactly do you mean by the drainage pipe? Is there even a way to build the outer layer without it resting on the foundation slab?

Why this wall structure: the development plan requires a plastered facade. We didn’t want external thermal insulation composite system (ETICS) with polystyrene, and a double-layer wall was cheaper than using ETICS with mineral wool.

The Poroton brick is placed on the outer edge of the foundation slab.
Insulation and the backing wall block are applied only on the foundation. So, in principle, this is correct.

I am just wondering how the garage will be clad on the outside? Will it be plaster applied directly to the Poroton wall only?