Basic Specification  
Installation Diagram - Coping
See Photo: OF COPING  

Copings and wall caps are usually an exterior application. However, interior wall caps and planters are not an unusual application for slate. Slate for exterior use should conform to A.S.T.M. C-629 for Class I slate and interior applications are Class I or Class II.

Clear Grade - Clear slate is free of Ribbons and most markings. It is a blue-gray to blue-black color and, if sealed, oiled or otherwise treated, it is approximately "jet-black". Clear slate is supplied in Natural Cleft, Machine Gauged, Sand Rubbed or Honed finishes.

Ribbon Grade - Ribbon slate is characterized by an ornamental dark band which, in the case of copings, usually runs parallel with the length of the coping. A ribbon may be wide, narrow or even double. In a wide coping, there may possibly be more than one ribbon. Note: Although Ribbon grade is not recommended for exterior use, with proper pitch and the ability to dry, a ribbon coping may be serviceable for over twenty-five years or more. Ribbon slate is supplied in Machine Gauged, Sand Rubbed or Honed finishes.

Face Finishes - Natural Cleft Finish is a rough textured, split face finish. The bottom is gauged to an even plane and the thickness, although varying due to the facial deviation of the cleft, is constant within the maximum thickness specified. (NOTE: The facial deviation in Natural cleft finish may appear more pronounced with regard to the edge plane in a long coping run.) Machine Gauged Finish is a smooth, even finish which approaches the honed finish. However, slight swirl marks are usually visible. Sand Rubbed Finish is a smooth, even finish with a slight stipple equal to about 80 grit sand paper. Honed Finish is a smooth, satin finish equal to about 240 grit.

Edge Finishes - Hone & Arris Edge is a honed exposed edge and either a 1/8" chamfer or a 1/8" radius on the top exposed edge to remove the sharpness. This may be specified in conjunction with any of the facial finishes, however in the case of Natural Cleft finish, the 1/8" radius is normally used rather than the chamfer. Arris Edge is the 1/8" chamfer or 1/8" arris on the top exposed edge without honing the edge. Sawn Edges are edges directly from the saw, which are usually very smooth and sharp as they are cut with a diamond saw. Other Edge Profiles are subject to availability of tooling and should be investigated prior to specifying.

Thickness - Coping and caps are supplied in 3/4", 1", 1 1/4", 1 1/2" & 2" Thicknesses. Other thicknesses are available to comply with special field requirements.

Treatments - Sealers usually darken the slate and give a glossy appearance. Natural cleft finish and Sand Rubbed finish may be sealed suitably, however, sealers may not adhere nor give a desirable appearance to Machine gauged or Honed finish. Impregnators usually do not as radically alter the color of the slate and give a more satin finish. As with the case of sealers, impregnators may not be suitably used on machine gauged or honed finish. Oiled Finish is usually a treatment reserved for interior applications. Oil darkens the slate without producing a sheen.

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  • Physical Properties
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  • The Structural Slate Company
    222 East Main Street
    P.O Box 187
    Pen Argyl, Pennsylvania 18072-01
    1.800.67.SLATE or Fax: 610-863-7016