Further technical information such as composition and manufacture, size and weight, performance and sitework...
Composition and manufacture
Contessa and Duquesa natural slates can be holed on site, by hand or machine, to produce the required size. The slates are holed from the bed towards the face so that the nail-head is accommodated in the small cavity formed by the area of spalling.
A full range of accessories is available. Consult manufacturer for further details.
Most slates have a secondary plane of cleavage or grain which can only be determined microscopically. However this grain should not be confused with the texture which can be seen on the surface of the slate, which is influenced by the direction in which the slate is split with a chisel, either from the top or the side. The slate has a normal texture using the classifications detailed in BS EN 12326.
Laid correctly, both Duquesa and Contessa natural slate will last the lifetime of the building and are ideal for use on major projects including supermarkets, schools, offices and prestige homes.
Cembrits natural Duquesa and Contessa slates are supplied directly to approved accounts, roofing contractors and building merchants. Prices are also available on request. Consult manufacturer for further details.
Duquesa and Contessa natural slates should be laid in accordance with the provisions of the latest edition of BS 5534:2003 and BS 8000-6:1990, and ventilated in accordance with BS 5250:2002.