A.Jeff Pitcher responds: It is possible to add a second layer of laminate, though it’s always best if you can remove the existing laminate and get down to a clean substrate. Unfortunately, there’s really no good way to get old laminate off unless it’s loose to begin with. If so, by using a torch and a putty knife, you may be able to remove what’s there. Don’t ever apply a second layer over loose laminate.
If the first layer is well adhered, scuff the surface with a belt sander and an 80- or 100-grit belt. The key is to break the slick surface, since most glues will not stick well to slick, nonporous surfaces. After scuffing the surface, wipe it with a solvent like mineral spirits or paint thinner. This helps the glue to "wet out" — meaning that...
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