On Mon, 1 Dec 2003 11:12:18 -0000, Christian McArdle wrote:

If a natural slate roof is unfelted, does this provide any
ventilation to the underside?

Ample, you ought to see the Tyvec flapping about under our slate
roofs. Once you re-new the covering and fit a sarking layer then you
need to worry about ventilation.

With what you propose I'd be more worried about driven rain/snow
getting in and running down the back of the celotex. Where is that
water going to go?

--
Cheers
Dave. pam is missing e-mail