On Monday, July 27, 2020 at 10:17:00 AM UTC+1, Andy Burns wrote:
George Miles wrote:

I've been using EDPM,

Did my garage/kitchen/porch about 12 years ago.
I did OSB3, then kingspan attached with foam, then OSB3, then EDPM

Why two decks?

First OSB3 was 18mm for the structure,
on top of beams.
Then a 2 layers of kingspan attached with foam
then thinnner osb3 foamed on it
(no screws or cold bridging,
and makes roof walkable)
then glued EDPM onto it.

[g]