We've had a builder provide us with a quote and they're due to start on Monday. I researched the vent 3 and I believe it's the high performance...
Thanks Palaceray, i'll have a look at those membranes.
I didn't know some authorities insist on the vents, that's good to know
we are having our roof replaced due to a number of issues.
with the old roof we had a lot of problems with condensation - we don't know...
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