Undercloak board with counter battens. Over or under counter batten?

[TimberFrame]

I'm going to be putting on a pitched roof (on a shed) using Redland Renown tiles, with cloaked verge tiles. I've decided to counter batten the roof to give a larger batten void (25 mm x2 so 50 mm ) and more air flow under the tiles. It seems like a good idea in terms of drainage over top of the roof underlay too. It will be a warm roof insulated up to the roofing underlay. In the Marley instructions, and according to a guy from Redland, an undercloak board should still be used with a cloaked verge tile to close the opening right under the edge of the claoked verge tiles. Which makes sense to me. The thing I'm wondering now is should I place the undercloak board over the counter batten, meaning the edge of the counter batten is basically visible if you look close (not a problem, just mentioning it for clarity to explain my thought process!), or under it meaning the under cloak board is as low as possible with respect to the verge tiles? There isn't much on cloaked verge tiles on the internet, and not too much on counter battens, so I couldn't find many relevant pictures etc.

[PeterW]

Cloaking board normally sits on top of the wall and is bedded on, with just the tile batten holding it in place. If you’ve got a timber structure instead , you may need some sort of timber trim up under the cloak and have the board sat on top of your edge counter batten - I’d make the edge one a 100x50 too and then carefully drill the cloak board in a few places to secure it with screws through the tile batten and then into the counter batten and the frame below.

 

Have you added up the weight of a tile roof as they aren’t light - is the shed structure up to it ..??

[TimberFrame]

Thanks for the reply. The shed will be timber framed, and it will be a substantial structure similar to US houses etc, so no problem with the roof weight. The rafters will have rafter ties to brace them against spread so the wall plate will only see the vertical weight. I think I will have to experiment a bit with the verge detail when I'm closer to doing the roof so I can work it all out. But it's good to think about and get other people's experience too so thanks.