I think you're right. There's a British Standard BS 8612 for dry ridge systems and it suggests the system, if fitted correctly and accredited to that standard, is weather tight...
Many thanks.
Thanks. 2 question then...
1. I've read the instructions for the Manthorpe system and they recommend 'when refelting the roof, leave a 5-8mm gap at the apex'. As my sarking felt overlaps the apex, presumably, there's nothing preventing me cutting this gap into the existing felt before...
I've got a standard trussed roof with sarking felt and wish to have the mortared ridge tiles replaced with the dry ridge system mainly because the mortar under the ridge tiles keeps falling away. Looking at the various dry ridge system manufacturers websites, they claim the dry ridge system...