In this segment, we will start to install some slate.
A typical slate nail is a 10 or 11 gage smooth shank nail with a 3/8” head. The length is 2 times the thickness of the slate plus 1”. Proper nailing is critical to the durability of a slate roof. Slates are intended to hang on the nails with the head set slightly below the surface in the countersinks left by the nail hole punching. Over driven nails can weaken the nail hole by blowing out the back of the slate. Under driven nails can cause the course above to be lifted slightly which can lead to breakage or an uneven surface.