David wrote:

On Fri, 20 Apr 2018 09:26:11 +0100, Handsome Jack wrote:

Tim Lamb posted
In message , David
writes
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?

Hmm.. builders seem to have latched on to the idea that porous roofing
membrane makes eaves ventilation redundant.

Building Control don't have the same view here! They insisted on a
significant gap between the membrane and any loft insulation.

When I insulated my new roof space I followed BC's instructions of
leaving a ventilation gap at the eaves (by not running the rockwool
right up to the edge). Now I'm getting birds roosting in the loft, and
leaving bird **** everywhere. Mind you it was just this last winter,
which was a pretty cold one.

That is why you have a board along the eaves to keep wildlife out, then
drill holes and put grilles in which have a mesh which stops birds, bats,
mice etc. getting in.

Cheers



Dave R

Or even a mesh which stops wasps getting in.

--

Roger Hayter