Electrical routing space of about 2 inches behind wall panels?

[Mikael_L]

Won't a 45 be too compressed?

In terms of insulation? Probably not.

But you risk "mechanical" problems. The panel might press against the interior wall panels so they bulge a bit, to the extent that it might be visible later depending on what paint/wallpaper you used.
Alternatively, the air gap against the outer panel might be compressed, especially if there is a wind barrier.

 

[Matti_75]

This space was exactly 28mm. If I want to insulate this space to get some extra insulation and soundproofing, what should I choose? A 45 might be too compressed, right?

Paroc has an insulation board that is 30mm thick. d^_^b

 

[Suhagg]

Lock/batten 22x170 + 16x45 on nail stud 28.
Exterior gypsum board 9 mm as external wind protection and bracing.
Solid stud frame 45x170, upright 45x45, 45x45
crossed (to avoid thermal bridges).
Mineral wool insulation 170+45+45 mm three-layer insulation.
Age-resistant 0.12 diffusion barrier and seam tape.
Pre-cut standing electrical/nail batten 28 mm on the inside of the outer wall
(simplifies electrical and plumbing installation and to avoid unnecessary
punctures in the diffusion barrier).
OSB/Gypsum

The idea is that the wall from the house manufacturer looks like this.
My thought then is to add 30mm insulation in this electrical installation space. A simple addition that doesn't change and increase costs. But it might not be good in other ways to have insulation here or what do you think? Thinking about the diffusion barrier.

The best and most affordable wall you get if you copy me.
panel
25x50 nail batten (but 28x70 is better, especially if you paint with exterior acrylic)
wind barrier (optional to have exterior gypsum, asfaboard instead)
horizontal 45 + 45 mm MW
vertical 195 + 195 mm MW
AB plastic
horizontal 45 + 45 MW + electrical conduit and possible water pipes.
OSB
gypsum.
Better but more expensive with fiberglass boards on the outside and/or light stud frame.

If I were to start changing to this proposal, for example, I suspect that there would be a lot of structural changes that would increase costs, new energy calculations (admittedly better) but the house manufacturer is likely to increase the cost significantly.