You've just laid tile and added grout. Now it’s crumbling and coming out. You can end this problem and stop making a mess if you know the five steps to grouting success. If you have a wood subfloor, be sure you use a concrete backer board. Make sure the thin-set mortar is not too dry. To check, lay a tile and pull it up to make sure at least 75 percent is covered. Don’t mix up more mortar than you can use in a half-hour. Mix your grout with an acrylic additive and use sanded grout on all joints over 1/8-inch wide. If you follow these five simple steps your grout will stay nice, and never will be a crumbling mess. Your kitchen- or bathroom floor will stay good as new. And that's the On The House tip for today.