Started out not to enthusiastic. Had bought a table saw to help cut up the ply instead of leaning over large sheets with a circular saw so was a bit nervous as to had I done the right thing. Seemed to work ok, stuck in and got all the walls covered, with reinforcements, but used a load of screws.
Having got the walls plyed (new verb) started on the big sheets for the ceiling. Let Liz drive the table saw with me holding the sheets and all went quickly. Had most of the job done by 1pm. Used the old hardboard sheets as templates for the awkward cuts and that worked really well. Job finished by 2:45pm. A successful day. Roof light cut outs are outstanding but will tackle that during the week. Liz went around filling in the bits of window area we had missed with the sheet ply, always was going to be a fiddly job, and I had to refit the mitre saw blade after it came loose.