The crate can be either wooden and metal (in this case, self -tapping screws are used for installation). To consolidate one sheet, you will need 20 nails or screws.
The overlap also depends on the angle of the bead, with which the slabs should be laid on each other (up to 10 groats-overlap up to 30 cm, 10-15 groats-overlap in one wave (up to 20 cm), 15 degrees and more overlap up to 17 cm.