Basement exterior staircase

If no building permit is required, then not. With us, exterior stairs are not permitted in the development plan. In other words: You have to apply for an exceptional permit. Then you need one. I, as a layperson, would equip the exterior stairs with a frost skirt and insulation. Why not? Under the house, I would not touch anything. The connection between the house and the exterior stairs is the decisive factor. No idea if it should simply be built on or if expansion joints are necessary.

Already a useful answer, thanks. I will inquire about the building application at the municipality.

So, a frost skirt under the stair landing slab, on 3 sides except on the house side, to avoid unnecessary undermining – insulate the frost skirts on the outside + the slab from underneath – maybe slightly extend under the house slab or align flush. Then continue the retaining walls exactly on the frost skirts. I would actually include an expansion joint.

Does anyone have other suggestions? :)

According to the building authority, no building application is required for a subsequently attached external staircase, only for a garage or similar outbuildings.

Does anyone else have a construction proposal, or anything important that the construction company should not neglect?