Floor construction Shed tiles

[Nimajneb]

I don't want to cast a concrete slab for a 15m2 "friggebod" but I want to have tiles in it.

How should I frame the floor joists and which sheet material should I choose to prevent the grout lines from cracking due to flexing in the construction and/or temperature changes?

The "friggebod" will be unheated.

 

[joflopp]

Regla as usual with c/c 600, apply 22 mm floor chipboard and then floor gypsum or fiber-reinforced floor leveling in at least 12 mm. For tips on which dimensions to use for the joists, you can check the Träguiden tables, I have collected the most common ones here.

 

[Nimajneb]

But is cc60 really enough, it seems like you are using cc30 in your bathroom.

 

[joflopp]

C/C 600 is the maximum distance, you can go down to 300. I chose 300 partly because I was constructing a partially existing floor structure and partly to be on the safe side.