Sealing may be appropriate for some grout installations after the surface has been properly cleaned and dried, but not every tile-and-grout system has identical requirements. Follow the grout, tile and sealer manufacturer's recommendations.
It helps grout resist absorbing spills and soil.
Cement-based grout in kitchens and entries benefits most.
Grout must be clean and dry before sealing.
Some grouts, like epoxy, do not need sealing.
Use neutral cleaners to help sealer last.
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