Whether you are installing a framed or frameless shower door, the procedure for installing shower doors on tile is basically the same as it is for drywall. The only difference is that you have to drill through the tile, and while that seems like a challenging proposition, there's nothing to worry about if you use the right bit and you take your time. When setting side frames, keep in mind that there is probably no stud behind the wall, so you'll have to install anchors to hold the screws.
Assemble the Things You'll Need
Apart from the tools you normally need to install a framed shower door, including a drill, caulking gun, 4-foot level, tape measure and goggles for safety, you'll need a drill bit that can bore through tile. A regular masonry bit will work, but if you want to do the job quickly and without risk of damaging the tile, get a diamond-tipped bit, which will go through porcelain, ceramic and even glass. You'll also need some masking tape to lay on the tile before you drill to prevent the bit from wandering.
If you know there is wood behind the tile, which is almost certainly true for the shower curb, you can use a 3/16-inch bit, which makes a hole just wide enough for a standard screw. If you know there's no wood, you need to install conical plastic anchors to hold the screws, and they need a wider hole. Match the bit to the anchor by comparing the bit diameter to that of the widest part of the anchor just below the flange. The bit should be the same size or slightly smaller than the anchor but not bigger because the anchor won't hold.
Install a Framed Shower Door
A framed shower door comes with a metal frame that has to be installed around the shower opening, which means you have to screw the top, bottom and side portions of the frame to the tile. Follow the manufacturer's instructions for the proper sequence, but usually the bottom goes first followed by the sides and then the top. Measure the opening dimensions and cut the pieces to fit using a hacksaw.
Before you set the pieces in place and mark the positions of the holes, lay masking tape on the tile. Besides stopping the bit from wandering, it will make it easier to mark the holes. Set each part of the frame using a tape measure to make sure both ends are the same distance from the front of the shower and using a level for vertical pieces to plumb them. Mark the positions of the holes with a sharp pencil.
Run the drill at medium speed as you drill through each hole to prevent overheating. It isn't a bad idea to stop and periodically dip the bit in water to cool it. After drilling the holes, tap in screw anchors if needed, set the frame in place and screw it down. Apply a bead of silicone caulk to both sides of the frame and install the door.
Install a Frameless Shower Door
Instead of a frame, a frameless shower door has hinges, and you screw these to the side wall using screw anchors to hold the screws. The most difficult part of the procedure is marking the holes, and the most accurate way to do this is to hold the door in position while a helper marks the holes. Don't forget to lay tape on the tile first and wear rubber gloves so you don't lose your grip.
After you've drilled the holes and set the anchors, unscrew the hinges from the door and screw them to the wall. Have a helper hold the door in place while you screw it back onto the hinges.
Chris Deziel is a contractor, builder and general fix-it pro who has been active in the construction trades for 40 years. He has degrees in science and humanities and years of teaching experience. An avid craftsman and musician, Deziel began writing on home improvement topics in 2010. He worked as an expert consultant with eHow Now and Pro Referral -- a Home Depot site. A DIYer by nature, Deziel regularly shares tips and tricks for a better home and garden at Hunker.com.