Floor joists with support beam on posts.

[Granngubben]

huggan, don't you think the pillars in the garage will be in the way? I would probably look at alternatives with fewer pillars if I were to build such a garage.

 

[huggan]

No, the pillars are placed between the cars where there will anyway be a net in between to screen off each parking space. The garage is intended for rental.

 

[Mikael_L]

...
Post: C14 45*145

Personally, I would go with a square glulam post 115x115 (120x120) without hesitation.
A beam is quite weak in the weak direction, and if you bump it with the car, it's easy for it to bend if there is a bit of load on top, which there is since there is an upper floor.
It would also look aesthetically better with square posts and it's not about many extra dollars. Doesn't Byggmax have posts on their website?

Although I think you should get a quote for everything from a nearby lumberyard, which should be able to beat Byggmax prices. But you do get a price indication from BM.

 

[huggan]

Yes, that will probably be the case.