Single-storey calculation exceeded - possibilities?

Everyone understood that beforehand except one....

No really? You are so clever.

You did indeed make a typo in #5 and wrote cm.

But the important thing: What consequences does this have in real life? Is there now a lack of space for furniture? Do some connections no longer fit? Is the already limited headroom above the bed now missing?

Does the contractor's proposed solution lead to a problem, other than that it would be built slightly differently than contractually agreed?

Countermeasures are only needed if a glaring problem arises that would not exist with contractual execution, right?

If such a problem does not exist, my advice would be to accept the change in exchange for legal certainty in the construction process.

The roof originally had a pitch of 21.5 degrees and a knee wall height of 1.59 cm.

After the modification, the company wants to build a pitch of 23 degrees and a knee wall height of 1.525 cm.

I would have understood the six and a half cm less, but the one and a half degrees more sounds very much like the principle of only not "losing" 0.50 and definitely not 0.51 square meters. Is there possibly no concrete consequence (in the sense of certain spots where you would bang your head or at least not be able to wear a hat) if one simply omitted the six and a half centimeters "without replacement"?