Stone Slate

Different types of roofs which can be covered with slate

Slate is a natural product which is manufactured manually in different shapes and thicknesses for multiple uses:roofs (new or to be renovated), floors, decoration etc. The following pages will help architects as well as private individuals to find the slate which suits their projects best.

Pavilion roof

The lines of intersection between two contiguous sloping sides join at the top of the roof. The base surface is a square, a rectangle or a polygon. The pyramid roofs or turrets can be pavilion roofs with very steep sloping sides.

Roof with two sloping sides

The roof with two sloping sides is the roof shape which is used most frequently. In the bottom part of a roof with two sloping sides, it is a good solution to adopt a change of incline (“coyau”).

How to calculate the number of slate titles per square metre.

UNCOVERED PART OF THE TILE x (width of the tile + width or thickness of the hook) = total surface of the “pureau”

1 m² : surface of the “pureau” = number of tiles per m²

Example for a slate tile of 400 x 200 mm, with a covered part of 85 mm:

  • 400 - 85 = 315
  • 315 : 2 = 157,50
  • 157,50 x (200 + 3mm) = 31.972 ,50 mm²
  • 1.000.000 mm² : 31.972,50 mm² = 31.28 tiles per m²

How to determinate the zone of covering and the slope of the roof

Slopein % Zone 1 Zone 2 Zone 3 Slopein degrees
Horizontal projection of the pitch (in m) Horizontal projection of the pitch (in m) Horizontal projection of the pitch (in m)
from 1to 5,50 from 5,50 to 11 from 11 to 16,50 from 1 to 5,50 from 5,50 to 11 from 11 to 16,50 from 0 to 5,50 from 5,50 to 11 from 11 to 16,50
20 153 - - - - - - - - 11° 1/3
22,5 147 - - - - - - - - 12° 2/3
25 141 153 - - - - - - - 14°
27,5 136 147 - 153 - - - - - 15° 1/3
30 131 142 153 147 - - - - - 16° 2/3
32,5 126 136 147 141 153 - - - - 18°
35 122 131 142 136 147 - 153 - - 19° 1/3
37,5 118 127 137 132 142 153 147 - - 20° 1/2
40 114 123 132 127 137 147 142 153 - 21° 2/3
45 107 115 124 119 128 138 133 143 153 24°
50 102 109 117 113 121 130 126 134 142 26° 1/2
55 97 103 111 107 115 123 119 127 135 29°
60 92 99 106 103 109 117 113 121 128 31°
70 86 92 98 94 101 107 104 110 117 35°
80 80 86 91 88 94 100 97 103 108 38° 2/3
90 76 81 87 84 89 94 92 98 102 42°
100 73 78 83 80 85 91 88 93 97 45°
120 69 73 78 75 80 85 82 87 91 50°
140 65 70 74 72 77 81 79 83 87 54° 1/2
170 62 67 71 69 73 77 75 80 84 59° 1/2
200 61 65 69 67 71 75 73 77 81 63° 1/2
250 59 63 67 65 69 73 71 75 79 68°
300 58 62 66 63 68 72 70 74 78 71° 1/2
375 58 61 65 62 67 71 69 73 76 75°

* This information is just given as an indication. It is not contractual and has been calculated after a request for classical slate.

The “horizontal projection of the pitch” is calculated as follows:

You can also calculate the weight of the slate per square metre, considering that the mass of good slate is 2.81 gr/cm3.

Example for a slate tile of 400 x 200 mm - thickness 5 mm - 31.28 tiles per m² :

  • Mass = 2.81 gr/cm3
  • 400 x 200 x 5 x 2,81 x 31,28 : 1.000.000 = 1.000.000 mm² : 31.972,50 mm² = 35,16 kg/m².