Statics - house with basement due to insulation, shifting Poroton bricks

During the construction phase, we noticed that the insulation of the basement is a bit too weak. Originally, 6cm perimeter insulation was planned on the outside, and now we want to go with 8cm insulation with a better WLG. The general contractor wants to shift the 36.5cm Poroton bricks 2cm outward for this.

I am a bit worried about the statics because the load will be transferred over a smaller area.

However, the construction manager and site supervisor said that it can be done.

What do you think?

Can you maybe say something about this as well?

Thanks a lot in advance!

Here is a picture again so you know what I mean. The basement walls are made of 30cm concrete C25/30.

What overlap do you then still have from the concrete wall to the first row of stones? 28.5cm plus or minus the accuracy of the mason?

What overlap do you have then of the concrete wall to the first row of bricks? 28.5cm plus or minus the accuracy of the mason?

Since the basement exterior wall is 30cm, I assume 28cm, plus or minus the accuracy of the mason. Construction is done with Poroton T9 36.5.

During the construction phase, we noticed [... / reason secondary] The general contractor wants to shift the 36.5cm Poroton bricks 2cm outward. [...] @11ant Can you maybe say something about this as well?

The general contractor wants to build the house 4cm longer and wider than approved? - I can already hear the chorus of my loyal readers thinking what I have to say about that.

I’m a bit worried about the statics, because the load will be carried over a smaller area.

It seems to me you are making naive connections here, and I don’t know the details of the base.

During the construction phase, we noticed that the insulation of the basement is a bit too weak. Planned was 6cm perimeter insulation on the outside and now we want to go to 8cm insulation with a better WLG. [...] The basement walls are made of 30cm concrete C25/30.

The signal phrase for my diagnosis "brain switched on too late" is right there in the introduction: "during the construction phase, we noticed" (wrong timing, you realize that yourself, right?). What exactly did you notice there: that the basement is now to be used differently, or why is the insulation of its exterior walls suddenly no longer appropriate as calculated?
I decidedly lack knowledge of your construction project to be able to elaborate here in a well-founded way. As far as I can follow your fragmentary descriptions, we are apparently talking here about a utility basement and a house with monolithic walls, caliber 365, on top of it. So far, so good. The basement is now to receive, with the basement shell unchanged, among other things, thicker insulation on its outside walls, 2cm thicker. This creates a delta regarding the "matching" exterior walls of the ground floor, naive calculation understood so far. If the ground floor is still being built according to the change in imaginary dimensions, the botched job pocket problem "the same in green" will remain—so far, so already different from good. Legally, even more than technically, different house dimensions are to be created here??? - Technically, as said, without project knowledge hardly any meaningful comment is possible.

The general contractor wants to build the house 4cm longer and wider than approved? – I can already hear the chorus of my loyal readers thinking about what I have to say on this.

It seems to me you’re making naive connections, and I don’t know the base details.

The signal phrase for my diagnosis "brain switched on too late" is right there in the introduction: "during the construction phase we noticed" (wrong timing, you realize that yourself, right?). What exactly did you notice: that the basement is now supposed to be used differently, or why is the insulation of its exterior walls suddenly no longer appropriate as calculated?
I definitely lack knowledge of your building project to be able to elaborate here well-founded. As far as I can follow your fragmentary descriptions, we are apparently talking about a usable basement and a house with monolithic walls caliber 365 on top. So far, so good. The basement is now supposed to receive, among other things, thicker insulation on its exterior walls with an otherwise unchanged basement shell, 2cm thicker. This gives, in that respect, a delta in the "matching" exterior walls of the ground floor, naive calculation understood so far. If the ground floor is still built according to the change in imaginary dimensions, the botched work issue will “remain the same in green” – so far, already different than good. Legally even more than technically decisive, other house dimensions are now supposed to emerge??? – technically, as said, without project knowledge hardly a meaningful comment is possible.

The basement was planned as a living basement. Usage class A and design principle A. Only the insulation was quite weak at 6cm WLG 035.

Yes, different house dimensions arise here. We have at least 0.5m space to the building boundary on all sides of the house. It is a development area with a zoning plan.

The question is what to do?

6cm insulation WLG 028 with U-value approx. 0.4 (then we build the house as originally planned) or 8cm insulation WLG 028 with U-value approx. 0.3 and move bricks.

Yes, different house dimensions arise here. We have at least 0.5m space to the building boundary on all sides of the house.

A house built differently than approved is an illegal construction, even if the building envelope still has some space. The consequences, of course, have a different degree of severity.

The question is what do you do?

I thought I had clearly written that: To those whose qualified opinion you seek, present the basics. We neither know your house design in general, nor, even less so, the plinth details. Thus, even with the greatest goodwill, your question cannot be answered.