Experts recommend thoroughly sealing your grout after any new tile work is done, but even those who have sealed it (or have had it done professionally) back when their floor, shower surround, or backsplash is newly completed should break out the sealer regularly (anywhere from every six months to a year) to keep that nice protective coating on your grout. You don’t absolutely have to, but it really cuts down on maintenance and keeps it looking mint for years to come. What does sealed grout have over non sealed grout? Well, by not allowing moisture or dirt to penetrate the grout, it relegates these things to the surface, thereby protecting the look of your lines.