Thanks I have posted on diynot.comWouldn’t it be better to go to a home DIY site like DIYnot.com where many professional trades people use the Forums. Plus your total lack of information about your problem isn’t very helpful.
Just thought there might be a roofer that owns a caravan that could give me ther advice ☺️This is a caravan forum Colin, so we're unlikely to be able to help.
House 120 years old. And I’m no roofer too 😂There's something not right there Colin, I would even question why there was such a wide wooden capping board in the first place with as Damien has said with the gap. The slates should go right to the edge covering the cavity and the capping would have done it's job, and no I dont claim to be a roofer, sorry.