Grades Of Roofing Slate

Greenstone slate is measured by eye to thickness and is then split by hand.

Grades of roofing slate.

A standard grade slate cupa h selection will be less uniform and will require more sorting prior to use. It is truly the result of a craftsmen s. This further highlights the traditional regional variations. Welsh slate being very flat and smooth as well as a nominal 5mm thickness.

Roofing slates are rated through the american standards of testing and materials and given a slate classification from s 1 to s 3. N is cupa s natural selection. Slate from cupa 5 and 18 quarries have more of a textured finish. But the finished project will look as good if due care is taken of the slate grading.

Standard grade rough texture. S 1 will provide a service life of over 75 years s 2 will provide a service life of 40 75 years. Welsh slate still comes in 3 grades referred to as capital 5 5mm thick county 7 mm thick and celtic 9 mm thick. Grade s2 slate s service life is 40 to 75 years.

Slate grades are intended as a prediction of the slates expected service life.