How do I minimize the thickness of the floor in a sleeping loft?

[oandersson]

Hello!
I'm planning to build a small loft in a garden shed and want to maximize the distance to the ceiling, i.e., minimize the loft's floor while still making it durable and without too much sag. The loft will be small, about 210x100cm.

My idea is to use 45x45 studs at 60cc (or closer?) and on that a 22mm chipboard which I would then put a regular foam mattress on. Under the studs, there will be about 6mm ceiling panel, which doesn't contribute to the sturdiness, but I want the loft to be rigid enough so the panel doesn't crack.

Will this hold? If yes, is it possible to make the floor even thinner than 67mm (ignoring the panel) and still have it be durable? Maybe there are stiffer/more durable boards than chipboards to use, for example? Or would a 30mm stud work with closer cc spacing?

 

[Småbrukaren]

I would not use 45, but instead buy 125 and split it in half, then mount it on its edge, about 60mm. A rectangular stud on its edge is stiffer than an equal-sided stud. Then you should use cross braces between the studs to distribute the weight laterally between the studs. Of course, it might work with 45x30, but the stud needs to be placed on its edge in any case.

 

[z_bumbi]

A box spring is self-supporting, making it a simple solution. Install studs in the wall and screw the bed into the studs.

Otherwise, most 22 mm boards can handle it if you account for them resting on studs screwed into the wall and some type of supporting fall protection. If you want it sturdier, add an extra layer of board. Around 30 mm plywood is hard to bend with a span under a meter and 44 mm is hard to bend.

 

[oandersson]

A box spring is self-supporting so that's the simple solution. Attach studs to the wall and screw the bed into the studs.

Otherwise, most 22 mm boards can handle it if you count on them resting on studs screwed into the wall with some type of supporting fall protection. If you want it more rigid, add an extra layer of board. Around 30 mm plywood is hard to bend with a span under a meter, and 44 mm is hard to bend.

There might be thinner ones, but most box springs are around 20-25cm, so it becomes a bit thicker than I intended. But double boards, for example, two bonded 22mm, must be rigid enough to attach a panel underneath and will be much thinner than framing up. Thanks for the tip!

 

[nimhed]

Put an iron from the 210 rule up on the ceiling and attach it there. There are nicer wrought iron to use.