Synthetic Slate
The most common type seen on roofs are of fibre cement but plastic, re-consituted slate and other types of synthetic slate are starting to make inroads. There are varieties of synthetic slates in terms of their colour, surface texture and edge. Many manufacturers now do plastic slates where the surface texture and dressed edge make the slates resemble natural slate. Fibre cement slates will tend to lighten with exposure to sunlight - natural slate holds its colour for much longer. Designs can be seen from the the Master Plastics site, one of many that supply such products. If you are considering these, then contact a local roofer to ask their experience with installing and ability to withstand fading etc.At the gable ends you will need to decide whether you want alternate rows finished with 11/2 width slates or single slates cut to half width. This is a matter of personal choice although using 11/2 slates is a better, more sturdy job. For a good job with synthetic slates it is best to still fasten the bottom of the slates with rivets - which will require extra holes to be punched both in the slate and in the slate underneath - some roofers will not put the time into doing this.
Clay tiles
Clay tiles can provide a traditional cottage style look with a range of grey/blue and red/brown colours. See the Clay Roof Tile Council site for their reasons to use clay tiles.Clay tiles come either as flat profile - see the Dreadnought Tiles site for examples or as interlocking type - see the Imerys site for examples.
Flat profile tiles are laid in a similar overlapping way to slates, being fixed by two nails at the top of the tile. Interlocking tiles are fixed with nails but their ridged profile means that there is little overlap, water instead being prevented from running through to tiles underneathConcrete tiles
There is a very large choice in these in terms of colour and, as with clay, the profiles are flat or interlocking. The main difference is that concrete tiles are cheaper than clay and they are heavier - which may affect the guage of the roof trusses, and makes harder work in handling.Ridge tiles
For slate roofs the options are, in the main:-- colour - usually a choice of red or grey
- lapping or butting
- roof pitch - obviously to match the pitch of the roof
Butting ridge tiles are sealed together with cement. Apart from having to deal with a bucket of cement up at the ridge, any cement that falls onto the slates will need to be washed away otherwise it will go off and mark the slates.
Lapping ridges tiles are usually, now, stuck down with a builders adhesive which is much easier to do, and no washing down. We usually put the ridge tiles on as the slates are completed, working across the ridge. Some roofers wait until the roof is complete and then simply push the ridge tiles along the ridge from one gable end, fixing the last ones at each gable with builders adhesive. You cannot use this method with butting tiles as the joints need to be cemented.
