they are not slates, boarding, counter battening and as much membrane as you like will not stop the channels blocking
got any bats? ecological survey?
maybe its unavoidable when he slates a roof.... Not good
As others have said, Underlay is not your weather proofing
ummm Well in this case it is!
do a sketch and some photos
or on holiday
two different tile types, need care to make a nice looking job. looking a bit poor can you post a few more pictures
Its a C*ck up, but saying that the leak is probably via the tile channels directing water in behind the upstand
simple , what you refer to as pepper pot, where we come from they are referred to as elephants foot ventilation cowl
Better than Google warriors I'd say.
rain probably following the profile of the elephants foot....pepper pot cowl into the flu.. It might look sealed but I bet it isnt....
overall not bad, pointing to hips is failing as is ridge pointing. (some poor patch pointing has been done)
Chimneys require attention too
flashings, we use code 5 but 4 is commonly used by others
lead soaker appears missing from flat roof to tiled roof
thats about it from the pictures, replace the gutter corner, re point stack
tbh honest it looks like a boiler flu has been used. f its really tricky to access then change it to a mushroom cowl.collar ,and an off cut of...
or .....stanley knife and straight edge, when the blade gets blunt snap the tip off and carry on
or fit the weathering collar properly ....currently hanging from the cowl
or if they are not supported properly on all four corners
some pads are adjustable, this allows the use of more rustic type of tile.
Are yours this type?
push up second course of tiles, remove first. Nail on comb filler replace tiles keeping them in line with the tile above.
gets tricky near hips,...
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