For all its aesthetic qualities, natural slate has limitations in that it cannot be formed into complex shapes. This means that weathertight construction in natural slate can only be achieved by significantly overlapping the slates, threefold at any point. The result is high labour costs, weight issues and performance limitations.

By contrast, an interlocking slate can achieve a weathertight layer through the use of interlocking weatherbars. This limits the amount of overlap required between each slate thus reducing the amount of material needed, with big savings in installation time and cost. Computer-aided tile design backed up by wind tunnel testing means that performance can also be enhanced allowing an interlocking slate to perform at far lower pitches.

Products that provide cost benefits on the one hand often demand compromise on the other. The BritLock, Rivius and Balmoral slates are an exception to the rule. These slates make use of natural materials with a riven finish to give a truly authentic natural slate appearance.

The following types of interlocking slates are available:



			Rivius	Large format interlocking riven slate featuring a riven surface and dressed edges.

			Cassius	Large format flat clay tile that provides a highly affordable clay roof covering.


			Balmoral	Medium format interlocking slate featuring a riven surface and dressed edges.



			BritLock Slate	The BritLock is a lightweight, labour efficient, interlocking slate manufactured from over 80% recycled natural slate waste.