Sizing flat roof without wind and snow loads

[Kortling]

I am going to build a freestanding room indoors with a flat roof. The span is 5.2 meters.

The construction from below is
Plasterboard
28x70 load-bearing battens cc600
45x220 cc 1200
Osb

Between the beams, there will be 195mm stone wool.

Is the cc measurement 1200 for the beams ok?

There are no requirements for stiffness, and it will only be stepped on from above when I lay the Osb on the top.

 

[blumenthal]

According to my wood sizing program (WoodExpress), it fails at the point critical stress. Unfortunately, I don't understand the calculations, so I can't explain why that would be the case. A 2x9-spar that is not loaded will obviously stay where it is. It's probably some deflection condition that is being exceeded.

Cc90 should be ok, however.

 

[Kortling]

Thanks for the reply. I have already put them out.
Maybe I'll have to arrange for some kind of support in the middle to help with it.

 

[witten]

It holds, you can load approximately 40 kg/m² on top of the structure.

 

[Krille-72]

It holds, you can load about 40 kg/m² on top of the structure.

Then only small children will be able to carry out future renovation work.

 

[witten]

Then it will only be toddlers carrying out future renovation work.

If there is to be a child on every square meter, then yes.

 

[Kortling]

Great! Thanks for the reply.