Bradstone Visit

Now that I have opened a discussion with Bradstone, things are moving on a little faster.  They sent someone out to inspect the roof today.  He agreed that the tiles were crumbling, and a percentage of them are in need of a replacement, and also agreed that these are indeed Bradstone tiles.  Previously we were not 100% sure on this.  He is going to speak to his management to see what they can offer us.  To help in their decision making he has asked me to send some drawings and area calculations, so they can prepare a "batten gauge" of what needs to be replaced, and cost the whole thing.
A batten gauge is a map of the batten positions.  Traditionally cotswold roofs are made of multiple different sizes of tile, and the reproduction versions are sold in the same way.  Each size tile is numbered, and the batten gauge tells the roofer what spacing to set the battens, and which number tiles to hang where.

Interestingly, he referred to the tiles as "roofing slates", not tiles, even though they are not made of slate.  I don't know if this is a Bradstone specific thing, or general in the industry.  Answers on a postcard (or blog comment) please.