You have seen lots of pictures of the outside of the roof. Now you can look at the roof from a different perspective, inside the roof trusses. A walkway runs down the centre of the roof trusses (image on L.), allowing people to access the truss space for observation and maintenance, if necessary. Looking down from the truss space (image on R.) you can see the poly vapour barrier attached to the underside of the roof trusses (and the blurry suites beyond the poly). Eventually the poly vapour barrier will be covered with fire-rated gypsum board on the inside of the suites. When the gypsum board ceiling is installed, R50 insulation will be blown into the truss space.