My brother-in-law has a house in the Outer Hebrides that leaks like hell after only a few years (around a velux window/ where a porch joins the house and in a bay window). It's wet and windy over there but this smacks of poor building standards.
And ideas what has caused this and how to cure it? (Glad it's not mine and that they don't live there permanently)
Holes.
Fix the holes.
Sorry we need far more information to be able to even guess at more sensible answers.
Mastic...............Lots n lots of mastic.
The midges don't like the smell of acetone based mastic and it will seal the 'oles as well
snipped-for-privacy@googlemail.com explained :
My guess would be that there is inadequate overlap of the layers of flashing, especially as I would imagine the wind speeds are quite high up there.
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