Thatched ridges on roofs in the UK and Ireland are almost universally made of straw reed or sedge; very occasionally turfs, heather and marram grass are also used. There are also some ridges which are concrete and we have sometimes fitted this type to roofs in Scotland.
In contrast most thatched roofs in Holland and France have clay tiles fitted to their ridges. The great advantage with these is there obvious durability. Whilst UK and Irish ridges will need to be renewed every 10-15 years clay tiles will probably last the life of the main part of the roof.
We recently completed such a tiled ridge on a property in South Wales owned by a Dutch client and which had previously never had tiles fitted. The before and after pictures show what a transformation this has made to the roof. The tiles in this case are grey but red ones are also available and we have also fitted tiles to ridges in France using the red ones.
The debate that British and Irish Thatchers will have about using tiles is that on the one hand it it will reduce the amount re-ridging work that is needed but on the other hand it should make thatch a more durable and therefore a more attractive proposition for builders and developers. In regard to the latter there is more new build thatching work done in Holland than anywhere else in Europe where all new roofs are tiled.
Advocates of British and Irish style ridges need not unduly worry that tiles will become the norm now or in the near future, firstly because some roofs will not be suitable to have tiled ridges fitted and secondly they would not be allowed on any of the 24,000 listed thatched buildings in the UK or indeed I suspect on roofs in conservation areas.
A Dutch firm of Thatchers in 2013 completed a new office building in Lancashire which has tiles fitted and pictures of this can be found in my blog entry of 3rd November 2013.