Dear Scott, Since i'm not sure what the cause of this would be, I can only assume that the plasterboard was left outside ;or in damp conditions and thus increasing any air particles in between the paper and plaster itself. I am suspecting an adverse effect on the preparation of anything you have tried from PVA to solutions. I must admit I'm not sure of this but i suspect that the plasterboard was kept in damp ;or wet conditions and in this , i feel this is why everything you put onto it it causes bubbles. Plasterboard is obviously dry upon sale but if kept wet; damp conditions ;or possibly cold may affect this ? I'm only guessing but it sounds like wet/ damp conditions my friend. Possibly air pockets that react to anything that you put onto plasterboard. paper could have been damp as well.
Anthony Tovey, September 2010
