How much does slate weigh?


Slate weighs between 800 to 1,000 pounds per square, or eight to ten pounds per square foot. The weight of each slate piece is directly related to the thickness of each piece of slate. The thinner the slate, the lighter it is. The thicker the slate, the heavier it is. Since all slate roofing material is still hand split today, the thickness for each slate varies according to the eye of the splitter.

    Most producers offer slate in several ranges of thickness:

  • 1/ 4” – 3/8” about 900 to 1,200 pounds per square
  • 3/8” – 1/2” 1,200 to 1,800 pounds per square
  • 1/2” – 3/4” 1,800 to 2,500 pounds per square
  • 3 /4” – 1” 2,500 to 3,300 pounds per square

The majority of slate sold today in the United States is 1 /4” – 3/8” thick.