On Thursday, April 19, 2018 at 6:09:15 PM UTC+1, David WE Roberts (Google) wrote:
Further into the clear out I've found some of those circular white plastic
eaves vents which allow air to circulate up the rafters, over the top and
down the other side. Hole saw as well.

Intended, I think, for boarded over loft ceilings where there is a risk of
condensation next to the roof.

Looking around, nobody seems to have them in this row of houses.

Are they still considered to be a good idea?
There an old idea of venting before the uses of breather underlay. The system was called cross flow system

The best way to stop condensation is to vent the ridge


Cheers


Dave R



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AMD FX-6300 in GA-990X-Gaming SLI-CF running Windows 7 Pro x64

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