All slates require a good level to skill and experience on the part of the slater. The most important facets of this is taking care in order to cope using the dimensional variations from slate to slate. In order to reach this one simpler and hence to ensure the slating pricing is reasonable; limits are set on the variations by size; width; edge straightness; rectangularity; flatness and depth; as well as there tend to be assessments for each of these. Most of these restraints do not apply at random sized slates simply because their dimensions tend to be undefined.

expertise and know how of the roofer