FPS Drop from crew compartments - normal?

[Boersgard]

I've had this minor issue for awhile now (maybe even in the base game?), where if I add any cockpit/crew module/service module after the first, it starts to progressively destroy my framerate. 2 modules is tolerable, but anything after that gets really bad. At 6+ modules I can start counting my framerate manually.

And it doesn't matter if the parts are even attached to anything. If I just select it and drop the red, transparent module in the SPH/VAB it will still cause an FPS hit.

Is it normal for this to happen?

Edited June 10, 2018 by Boersgard