Types of Slate
* Natural Slate (many grades and regions available)
* Fiber Cement Slate
* Cambrian Slate
* Natural Slate (some slate regions include)
-Spanish, Chinese and Welsh
Kent Roofing Contractors will supply natural and man-made slate and our highly skilled and experienced workers will fix the covering to your roof structure.
Reasons to use slate products as a roof covering include;
Conservation – some roofs are in conservation areas so if they have a slated roof this must go back the same. Providing the roof covering is like for like and thermal qualities are not reduced there is no need for planning permission.
Appearance – Many of our customers opt for a slate roof because it is aesthetically pleasing and stands the test of time much better than any other roof covering. We have even completed projects that entailed us removing a tiled roof covering and replacing with slate purely for cosmetic purposes.
Moss Build Up – Moss build up is one of the first things that spoils the appearance of a roof and over time can; break down cement work, block gutters and damage the roof structure. Natural slate provides the highest moss build up prevention.
Fiber Cement Slate
Fiber cement slates are a cheaper option to natural slate and from a distance can give the same appearance. They are easier to work with and the economies of scale are more rewarding. However they are not as good at repelling moss growth and their appearance does not maintain attractive last as long as natural slate.
Cambrian slate is a single lap system that gives a slate appearance, oppose to all other slate products that have a double lap. This product has a very long life expectancy but it not a good option if making later alterations extension dormers etc. the reason being the slate is nailed and clipped and once in place it is very difficult to remove
Slates are more costly roof covering than a tiled roof, this is due to that fact slate is more time consuming to fix than tiles as every individual slate has to be aligned and fixed into place with two nails, also the cost of the slate is generally more expensive per square meter that a tiled roof. Slate Cost cost vary depending on slate from 85 pence each to £2.50 each slate
What Slating Involves
Positioning the battens
The spacing up the roof between the battens is known as the gauge, this usually varies according to the size of the slates, the pitch of the roof and the degree of exposure. The battens have to be set out so the slate sits half way on the batten and in position for the slate holes to be fixed
Laying the slates:
Slates are laid on the battens in a ‘brick bond’ pattern, i.e. with the joints between them aligned with the center of the slates above and below, and with about 3mm between the side. This layout gives a double lap covering.
The top row of slates at the ridge is also made up of half slates to give the next row down a double lap. The top edge of the second row down must be at a level where it will be covered by the ridge tile.
Cutting the slates:
Slate is by nature a layered material which can tend to flake.
Using a pair of slate cutters is the preferred option, (these support both sides of the cut underneath while the cut is made by a blade coming down between the supports).
Alternatively a guillotine, grinder or brick laying trowel can be use to chop the slate.
Fixing the slates:
Aluminum nails or copper should be used in preference to galvanised nails as aluminum will not corrode whereas the galvanise coating will tend to. Alternatively copper or stainless steel nails can be used.
Slates can be either nailed at the center line or near the top. When slates are nailed at the top, the nails are covered by two slates and so are less exposed.
Most artificial slates come with the holes already drilled, where necessary nail holes should be drilled at least 30mm in from the edge and 25mm in from the top.
The slates fitted to the verge are 50% wider than the rest, this ensures that the pattern is maintained without having to cut down and use half width slates at the verges.
Sometimes half width slates are used down the verge underneath the other slates to form a triple lap, this has the effect of tilting up the end slates so that water tends to run onto the roof rather than over the edge.
The edge of the slates project about 50mm over the edge of the verges and any space between the lower side and the verge is filled using mortar or a timber trim can be fitted to the underside of the side of the slate overhang to finish.
The ridge and hips are finished with ridge tiles normally blue or red terracotta angular style or lead flashings .
The ridge tiles are bedded on and jointed with cement mortar (3:1 sand:cement), it often looks better if a coloured pigment is added to the cement so that it is similar to the ridge tile
call now for a quote from your slate roof in Herne Bay. Ballman serve all of Kent and are your number one roofer in Canterbry