Timber frame construction with or without 60mm installation shell?

Good day,

our house construction company leaves it up to us whether to build with or without [Installationsschale].
What recommendation is there regarding this?

Best regards, Wanderjupp

I would definitely not build without an installation layer.

Great effort is made to make the "main dam level" as airtight as possible, so why should it then be penetrated with numerous holes for sockets, lamps, pictures, etc.?

An additional insulated installation layer with OSB + drywall in front allows easy mounting even of heavy cabinets with normal screws. No plugs, etc.