ᐅ Which type of flooring is suitable for the attic?

Hello,

Our single-family house is currently under construction. The rafter fields of the roof slopes and the ceiling areas on the upper floor are being insulated with mineral wool mats. A plastic sheet is planned as a vapor barrier beneath the mineral wool mats. The cladding will be done with drywall panels.

I have a question: The attic space is unheated (cold roof) and ventilated through the ridge. We want to use the attic as a storage room.

What type of flooring is best suited for the attic? What should be considered?
Is it possible to lay the flooring directly on the collar beams?

Thank you very much

In most unfinished attics, tongue-and-groove boards are used. Depending on the rafter spacing, the thickness of the tongue-and-groove boards should be taken into account. I have a rafter spacing of 90cm (35 inches) and chose a thickness of 22-23 mm (about 7/8 inch). This is very suitable for normal storage use. Of course, if you plan to store something extremely heavy, like a ton of gold bars per square meter, you should consult a structural engineer.

Hello,
just a thought:

Depending on the structural system, it may be necessary to design the collar beam layer as a diaphragm. There should be a note about this in your structural calculation.
If this is the case, there are some special considerations to keep in mind during execution.

Regards, w - bpb

Hello,

what does it mean: Depending on the structural system, it may be necessary to design the collar beam layer as a diaphragm?
What should I understand by that?

Regards