PAINTING PROCEDURE
If Glulam has been pre-primed, the protective coating primer may tend to deteriorate over a period of time and become slightly chalky - unable to bond adequately to any additional coating systems without some preparation work.
A simple way of testing whether there has been any deterioration is to cut a small "x" through the existing coating system with a sharp blade. Press some cellulose sticky tape firmly across the cut and then rip off the tape. If any of the coating comes off with the tape then the primer is not adequately sound and must be removed by sanding.
Sand back until the surface is completely free from all dirt and degraded material and dust off. Prime all surfaces, paying particular attention to cut ends and joints, with a good quality solvent-based alkyd primer. Water based primers are less effective in this application. Allow to dry as per the manufacturers instructions and lightly sand to an even finish. Apply two coats of premium brand acrylic exterior grade top coat to the manufacturers recommendations.
