Knee wall height / Proposal from the building authority

In the example posted by Yvonne, I still think that both eaves sides are the same height; however, the mix of cladding and plaster can be deceptive. Clarity would probably only come from a picture of the opposite gable side, as the roof extension on that side is designed to be open at the front.

I didn't measure it now, but I paid attention again today (I pass by the house every day): the eave heights are the same on both sides, only the outer wall of the right entrance side is set back.

Source: Schwörerhaus The eave heights are definitely not identical according to the picture. Depending on which height is actually measured, the right eave height is either higher or lower than the left one.

when measured at the intersection according to Bauexperte, the right side is higher than the left

I will take a photo

In the end, it doesn't really matter whether they are the same height or different heights.

What is important is which exterior wall is used for calculating the eaves height. The projecting wall, as the building authority suggests (as is measured for example with double facades), or the actual house wall, as the construction expert suspects.

If it really were as the construction expert suggests, what happens then when the currently open sides are glazed? Does the point for measuring the eaves height then move outward?

On the topic of nationwide uniformity, it is not even uniform within the same federal state....

Development Plan Ludwigslust (textual specification)

The eaves height of new buildings and conversions must not be less than 2.80m and must not exceed 3.50m. The eaves height is defined as the distance from the ground surface to the underside of the eaves box or the distance from the ground surface to the underside of the slanted eaves board.

Development Plan Stralsund (textual specification)

2.1.2 The eaves height is defined as the intersection between the rising masonry and the outer roof covering.