Back Splash Tile Over Old Sheet Rock?
You can put the backerboard over the drywall. Tile backsplash is often placed directly on the drywall, because there's not much chance of a lot of water getting through to cause damage. You will need a fairly flat surface though. If the face paper on the drywall has been compromised by removing the old laminate backsplash, it may be easier to add the backer rather than try to smooth out the drywall....
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