I'm replacing a ceiling. As it consists of 3 sheets, backblocking is required; because of ceiling access backblocking has to be done from below, at time of install of the sheets.
There's a elapsed time issue in all this; cornice cement sets in 45 minutes, so the sooner the sheet goes up to the backblocks covered in wet cornice cement, the better. Also, however the sheets will also be glued, the acrylic adhesive also has to be applied to the rafters and the sheets put up before the adhesive skins, as Rod has warned us.
So what's the best sequence? Do I apply adhesive, then mix cornice cement, apply that and fit the backblocks, and then jack the sheet into place? How long can adhesive be applied to rafters before it skins?
So many projects, so little time ...cheers!