Where I am in Europe, it's standard for all interior framing (walls and ceilings) to be made from steel profiles. They are strong enough to hold up walls and doors, so I guess a workbench could work.

They come in standard lengths, so for walls you pretty much just lay them down and join then with self tapping screws. They even come with cutouts for wiring to pass through.

https://www.mfo.pl/en/drywall-framing-steel-profiles

External and structural walls are built from masonry.