Dimension mezzanine floor?

[trojlee]

Will start with the dloftet on our attefallshus. What dimension do I need for the joists on the intended loft?

It is 320cm wide and 240cm deep.
Thank you in advance.

 

[Tompafix]

I will start with the loft in our attefallshus. What dimension do I need for the joists in the floor of the proposed loft?
[image]
It is 320cm wide and 240cm deep.
Thanks in advance.

What is intended to be under where the loft ends? Will there be a wall that can bear weight, or should it be open underneath?

 

[trojlee]

It is an open floor plan. Possibly a small toilet in the upper right corner that can provide some relief.

 

[Gabbe1]

My gut feeling says that you can make do with 45x120 (c-c 60 cm) on the rafters, which need to be 240cm long.
But then you'll probably need a glulam beam (320cm long) to attach one end of these rafters to.

 

[trojlee]

What dimension should the glulam beam have?

 

[Tompafix]

If you place the joist in the other direction, no beam is needed. 3200mm is not a long span. You just need to increase the dimension of the floor joist a bit. Should it be dimensioned for residential load or just hold for two people plus a bed?

 

[trojlee]

It's for two people and just one bed.

 

[Tompafix]

It depends a bit on what you prioritize. A few extra cm in height, at the cost of more beams. This table is made for residential load, so you can easily go down a dimension if you want, but then you have to accept a bit more deflection over time. 195mm with screw-laminated floor chipboard is more than sufficient at cc600mm