Slate is a natural product and each slate is therefore unique. As a result, to ensure a roof that looks good and performs well, all natural slates should be sorted in accordance with BS 8000.
Sorting Natural Slates on Site
Slate sorting is most easily done at ground level. Any twisted or bowed slates should be set to one side, and be used first for eaves or top slates. This will result in the best possible roof finish. Not sorting slates, particularly amongst the Commercial and Classic ranges, can compromise the aesthetic appeal of the roof.
How to Store Natural Slate on Site
Slates should be stored in their pallets wherever possible. Once removed from the crate, they should be stacked on their long edge on two pieces of batten. Each slate should be inspected and separated into three piles;
Thick slates should, ideally, be used at the lower roof
Medium thickness slates used in the middle of the roof
Thin slates should be used on the upper roof.