Ceramic Tile

I like ceramic tile, and in normal situations, it is easy to install. I'm talking about tile on walls, counter tops, floors, and in showers. This discussion does not include marble or granite.

Types of Tile
      There are several grades of tile, and when you go shopping for it, you will see them all. The harder or porcelain tiles are what I prefer. Not only are they more durable, but IMHO they are more attractive. They come in all sizes from roughly lxl" mosaic tiles up to 18x18" or even larger. Mosaic tiles and some small tiles are supplied as 12x12" sheets, held together by a mesh backing; you install the tile sheets with the backing in place. Some smaller tiles, up to about 4x4 (actually, 4-1/4" x 4-1/4") have a high gloss finish. There are places you can use these, but they are generally not very tough. Don't use them on floors or kitchen counters since they scratch easily.
      In addition, you will find several types of edging tiles: bull nose, double bull nose for corners, V-cap that goes over the counter edge and corner V-cap, and quarter round tiles for edges, along with corner quarter round. The quarter round edging is usually used to cover the edge of backerboard. For example, if you installed backerboard over drywall somewhere, the quarter round can cover that edge. For the edge of a counter, you can use a bull nose tile on top and a half of a bull nose tile on the face edge of the top, with the bull nose down. But I prefer the V-cap edging on a kitchen counter because it is tougher. It also has a raised lip to contain water on the counter top.
      The bull nose tiles are the same size as the field tiles. The V-cap and quarter round tiles are usually 6" long. In some patterns there are special tiles for around sinks. Also, base molding tiles for floors. Bull nose are generally sold by the square foot, but other edging tiles are sold by the linear foot. Something the novice will find odd is that while many tiles are 4-1/4" square, the matching V-cap or quarter round tiles are 6" long. The reason is that it is usually very difficult to line up the field tiles and edging tiles, so with the longer edging tiles, you don't need to try to line up the grout joints. However, if you are using the bull nose treatment on a counter edge, line up the tiles on the top and the edge.
      Check the tile size carefully. I have seen some newer tiles in odd sizes, such as 4-1/2" square. At first glance, these appear to be 4-1/4" square, but trying to match them to other 4-1/4" tiles can be a disaster. I have no idea why these odd sizes are cropping up.
      There are a couple types of pavers: Quarry tiles that are hard and typically orange-red or dark tan in color, with a dull or satin sheen; Mexican pavers that are sometimes quite irregular in shape, size and color; Saltillo tiles that are similar to Mexican pavers but are more regular. The Mexican pavers are soft and usually need to be sealed.
      With all that, every time I go to a tile store, they seem to have some new sizes and shapes. As an example, there are patterns that are made from two or three sizes of the same or companion colors. Some of these can be quite attractive. Bedrosian has a website that illustrates several tile patterns that might give you some ideas.

Accent Tiles
      There are places where you can use special accent tiles to add some class to the design. There are slender "sizzle strips" that can be used on walls; these are sometimes an accent color and usually a special pattern like a rope or ridges. One way to use these is as a row around the room just below the top row of bull nose tiles. They act like a visual chair rail. They can be used similarly on a counter backsplash. Another type of accent tile is a special color or pattern of field tile used to break up the monotony of the field. These can be a pressed flower pattern in the same color as the field tiles, for example. Another type of accent would be a small tile or strip tile used as a border around the outer edge of the floor. In a floor, large tiles can be set with small companion tiles set diagonally in some of the corners.

Figuring the Amount of Tile
      On a counter or wall, start by working out the edging tiles and then go to the field tiles. Once you have the edging worked out, the rest of the layout becomes easier. You will probably find it easiest to figure the edging tile by the linear foot, and then count the double bull nose or quarter round corner tiles you need. You usually buy field tile by the square foot; field tile is the standard tile you use in the center of the field, not including edging tiles. If you have figured out what you need by the tile, the salesperson will convert that to square feet. Always allow about 10% extra tile for breakage and odd cuts, except count the exact number of corner tiles needed, and order a couple extra of these.

Tile Layout
      Spend some time with this and you will be rewarded. On a counter, you will probably have a sink somewhere. Center the tiles side-to-side around the sink because this is a focal point, and work from there. Use full tiles at the front of the counter and cut tiles in back or on distant ends. If you find that the sink is just in the wrong place to get the best tile layout, consider moving the sink slightly to improve the pattern. This will require adjustment in the sink drain below, so think out the plan carefully before committing.
      For floor tiles, many sources talk about snapping chalk lines and starting the layout from the center of the room. I seldom find that satisfactory because it usually requires cutting all of the tiles around the edges, and that gives a ragged or choppy appearance IMHO. I think it better to consider first using full tiles at the door and work from there. Lay out some tiles dry and see what looks best to you. Floor tiles, particularly large square tiles, also look good when laid diagonally; this breaks up the size of the room visually. "Railroading" tiles on a floor (setting them straight in long rows) can be very distracting, and if your rows are not perfectly straight, it will be very obvious.

Counter Tops
      There are plumbing considerations on counters, and you will have to decide on the sink mounting and positioning. There are two common types of sinks for use with tile; the most common is the type that sets on top of the tile, the "self rimming" or overlay type. These are easy to work with. For a kitchen sink, you can sometimes get them with squared off corners so they can be set flush with the tile. These give a nice appearance and there is no edge to catch water and food; they make for very easy maintenance and cleanup. For this type of sink you need a strong support that will hold the sink at the correct level with the tile, and you may have to shim the sink to achieve this. If you are working with a plywood top, you should add something like horizontal 1x4 or 2x4 bracing under the plywood at the edge of the opening on the sides and possibly the back. If the sink cutout is almost over cabinet structure below, additional bracing may not be needed.
      Most kitchen and bath sinks have a rear lip for the faucet mounting. With some bath sinks, the faucets will be mounted on the counter nearby. It is important that in positioning the sink that you give yourself enough clearance for mounting these items, including enough clearance to get a wrench in there. The other factor is that if you are using a V-cap edge tile in front of the sink, it is best to not trim that to fit around the sink. Most sinks come with a template that you can use to mark the cutout.

Backing
      Generally you need a tile backerboard under tile set horizontally. A backerboard is more water resistant, somewhat stiffer, and it gives a surface that the mortar will adhere to better. It will also expand/contract much like the tile and separate the tile from the expansion of the substrate. Hardibacker (my preference) comes in 1/4" and 1/2" thicknesses and is essentially waterproof. The various brands of cement board (Durock and Wonder-board are two brands) are usually 1/2" thick and they are not waterproof. Plus they are heavier and very hard on the hands and unpleasant to work with. I have also had them fracture around fasteners and at the edges. For these reasons, I avoid them. Denshield is a drywall type product with a water resistant facing but it is not suitable for tile in wet locations; I don't recommend using it. If the waterproof surface is damaged, the board is no longer waterproof.
      For a bath counter you can get by setting the tile directly on plywood if it is fastened down solidly and supported well. But it would be better to lay 1/4" Hardibacker over the plywood. You can also set tile on synthetic marble ("cultured marble") or formica-type laminate if you rough it up first with sandpaper. Laminate surfaces can fool you; you may think it is on solidly only to find out later that it wasn't. It would be best to set 1/4" Hardibacker over it to be sure. If you want to set tile on a synthetic marble top with a molded sink, you will have to cut out the molded sink so it can be replaced with a new sink. You can do this with any power saw you have with a carbide blade, or with an angle grinder or a router. You may also have to grind off a lip around the edge. For a kitchen counter you should use a backerboard. You can use the 1/4" Hardibacker over plywood or over the wood slats; if they seem loose, use 1/2" Hardibacker. Sometimes it is better to use two layers of 1/4" Hardibacker and overlap the joints to give a more solid base.
      For any backerboard, allow about 1/8" gap between sheets and don't allow four corners to come together anywhere. Apply self-adhesive alkali resistant fiberglass mesh tape over the joints; you can get this in the tile dept of a home center. Don't use drywall mesh tape. As you set the tile, the joints will be filled with thinset to seal it. To install Hardibacker, set it in thinset and screw it down every 8" each direction; if you want more instructions for using Hardibacker, you can get them from their website. They talk about scoring and snapping it but that has not worked too well for me. I usually use a power saw with a carbide or dry diamond blade. The dust is not pleasant; wear a mask. To make curved cuts, you can use a jig saw with a carbide grit blade or just use a regular blade and expect it to be eaten up by the material.
      For wall tile you can set the tile directly on drywall if it is in a place where it will not get wet, like a backsplash on a kitchen counter. Otherwise use 1/4" Hardibacker over greenboard or drywall; cement the Hardibacker to the wall with thinset and screw it to the studs every 8". If you are working with open studs you should use 1/2" Hardibacker with roofing felt behind for a moisture barrier. If you want a flush surface to adjacent drywall, remove the drywall in the tile area and set 1/2" Hardibacker in its place. Caulk that joint with a non-hardening caulk like butyl rubber or polyurethane caulk. Silicone caulk is not satisfactory! Plan the layout so the tile will cover that joint slightly.
      For concrete slab floors, you don't need any backing; concrete is about the best substrate for tile, if it is in reasonable shape. If there are small cracks, lay wide fiberglass mesh tape over them to help absorb any stress. For larger cracks that have been there a while, use the same method. If the concrete level changes at a crack, you need to smooth that out with an angle grinder or other power tool, and then use the mesh tape. As you set the tile, the thinset mortar will fill these cracks, through the mesh tape, and help stabilize them. The concrete slab must be reasonably level since the tile will follow the level of the slab. Use a floor leveling compound to fill depressions; you cannot depend upon the thinset to fill them. You need a leveling compound that will adhere reliably to the concrete, such as a latex fortified cement material.
      For wood floors, you need more than just 3/4" plywood or wood boards. If you have no noticeable bounce in the subfloor, you may be able to use 1/2" Hardibacker over the wood. However, current practice calls for a wood subfloor 1-1/8" minimum thickness under the backer. Cement it down with thinset and screw it down. Tape the joints with alkali resistant mesh tape; allow about a 1/8" gap between sheets. Stagger joints and don't allow four corners to come together anywhere. If you cannot get the 1/2" thickness, you can use two 1/4" layers cemented together. Cement and tack screw the bottom layer down to keep it from shifting and cement and screw the upper layer over it, with screws spaced every 8" each direction. Be sure to stagger the sheets in the second layer; this is very important. The latest thinking on cementing backerboard to a wood subfloor is to use standard thinset; use latex modified thinset between layers of backerboard and for the tile.
      There are special screws to use with Hardibacker. These have serrations under the head that will countersink better. The last time I bought these, they had a square drive head and a driver bit was included in the package. They worked very well! In a pinch you can use deck screws, as long as you don't overdrive them; you can get them with a square-X head for easier driving using a square bit. The heads will stick up a small amount but this will be absorbed into the thinset layer as the tile is set. I have tried the special screws made for the concrete boards and was disappointed in their performance; they didn't countersink even as well as drywall screws. Nailing is allowed but I don't think nails hold as well. The nails to use are roofing nails with a large head.

Uncoupling Membranes
      In some situations an uncoupling membrane might be the best backing material. I have seen these recommended by tile pros but have never used them. The talk is of Schluter Ditra, and this information comes from their website. This is a high density polyethylene mat with a patterned underside coated with fleece to facilitate anchoring to the substrate. You use latex modified thinset to fasten it to wood and unmodified thinset to fasten it to concrete. The top surface has a grid pattern with undercut spaces to assure a firm fastening, and you use unmodified thinset for the tile; modified thinset on top of the Ditra will not cure in a reasonable time. I see the advantage of this product on a concrete basement floor where there is a potential moisture problem, but I like the idea of Hardibacker over a wood subfloor.

Showers
      Showers are in a class by themselves, and you start with the base. A waterproof pan is required under the base of the shower. You can use a hotmop tar waterproof pan or one of the newer plastic membrane pans. Let me describe the process to see if you want to tackle this yourself; I suggest you may want to have a pro make the base or at least the waterproof pan.
      Start by positioning the drain, preferably at the center of the base, but it can be offset. Connect the bottom half of the drain fitting to the drain pipe and position it in place by whatever means necessary to hold it firmly. The shower drain fitting comes in two parts that clamp above and below the waterproof pan. You need a sloped mortar base; slope of 1/4" per foot from that drain fitting to the outer walls. This is very important to assure that any leakage will end up down the drain. Use a level to establish that pre-slope and set small wood strips around the edges to give that slope. You will need several strips of wood to act as screeds because you are working in tight quarters and the distance from the drain to the sides and the corners is different. Lay roofing felt on the subfloor and wire mesh or expanded metal over the roofing felt. If this in on a concrete slab, paint the slab with latex additive instead of laying roofing felt. Mix a small batch of mortar very stiff using latex additive instead of water because it will be a thin layer; set it in place, screeding from the drain to the outer screed strips. Make this layer of mortar as smooth as practical. You can leave the outer screed guides in place, or remove them and fill the space with mortar. This mortar pre-slope will have to cure at least overnight and preferable 3-4 days for a hot mopped pan.
      Now create the waterproof pan. I have more faith in a hot-mopped tar pan, so that is what I will describe. The shower curb in front is typically three 2x4s stacked flat, to give a form about 4-1/2" high. I would use pressure treated wood. Fasten them securely to the floor by nailing or with a powder nailer on a slab. You will need 2x blocking between the studs at least 10" high all around; I suggest 2x12" blocks. Now lay out one layer of 30# roofing felt over the inside of the shower bottom, up to the top of the blocking and over the curb in front. Fold it neatly in place and fold the corners over themselves to avoid cutting them. Piece this as necessary, but as little as practical; staple it in place at the top of the blocking and on top outside of the curb and at the bottom of the outside of the curb. Precut two more layers of the roofing felt and set them aside for now. Slather on molten tar with a small mop over all this roofing felt and seal any laps in the felt. Add the second layer of felt in the hot tar. Poke it in place as tightly as practical with a wood block. Then slather on more molten tar to seal the seams and the face of this second layer of roofing felt. Repeat this process for the third layer. You will end up with a very solid waterproof pan with a tar face.
      When it cools, locate the drain hole and the bolt holes in the lower drain piece; cut tight clearance holes around the bolt holes and the drain hole. Set the top drain piece in place and bolt it down. The tar does not need to be molten for this step; just clamp the two halves of the drain on the waterproof pan firmly. Note that there are three bolt holes and three other holes; the other holes are the weep holes that allow leakage to go down the drain. Put a small amount of pea gravel or cut up tile spacers around those weep holes to keep mortar from blocking them.
      You now have a waterproof pan, and you need to test it to be sure it is indeed waterproof. Buy or borrow an expanding rubber plug for the drain, set it in place down low in the drain and fill the pan with water. Mark or note the water level and check it 24 hours later to see if you have lost any water. If all the water is lost, look for a leak at the drain fitting, or more likely, the plug was not fastened well enough. If just a little water was lost, look for a leak in the pan, or the drain fitting may not be fastened tightly enough. With the pan holding water - a real confidence builder! - drain the water and proceed.
      When using a plastic membrane pan, the process is roughly the same. However, there is much greater risk of a tear in the pan or leaking seams, and you will have to work with a plastic cleaner and solvent cememt. For more details, with illustrations, get a copy of "Setting Tile" by Michael Byrne. He talks up the plastic membrane method, but I read that he is backing away from it since writing that book, if only because a homeowner may not have access to the materials.
      A third material you can use for the pan is one of the Schluter products. Read the material on their website.
      Now on to the shower walls. Set 1/4" shim strips on the studs above the pan and fasten 1/2" Hardibacker in place. The backer should rest on small blocks over the bottom of the pan to keep the backer from damaging the pan. First put a waterproof membrane on the wall studs behind the backer and overlapping the top of the tar pan; roofing felt is preferred. Leave a small gap (no more than 1/8") between sheets of Hardibacker. Tape these joints with alkali resistant fiberglass tape; it is self-adhesive. Before setting the backer in place, coat the lower back of the backer with a layer of modified thinset to brace it to the pan, and screw the backer to the studs ABOVE the pan, on up. Also install a strip of backer on each side of the shower opening. Be sure not to pierce the pan at any point. Remove the small blocks from under the backer. Caulk that lower edge of the backer to assure that water will not wick up into it; use butyl rubber or polyurethane caulk. Set the backer on the walls all around. Except, you cannot use backer on the inside of the curb, because you do not want to pierce it with fasteners. However, you can use the backer on the outside of the curb.
      Set wire mesh or expanded metal over the top of the curb; crimp it so it hugs the curb. Extend this into the base of the shower a few inches, and fasten it to the top outside of the curb, or stuff it behind the backer there. Use a straightedge across the inside of the curb to assure that the metal does not extend beyond the face of the backer inside on the walls. Mix a small amount of stiff modified mortar and cover the inside face of the curb, level with the inside backer. Let that cure overnight.
      To maintain the slope of the mortar base, put masking tape around the inside of the walls, leveling it carefully. Now mix mortar for the shower base. For all these operations with the mortar in the base, you may be able to find bagged thick-bed mortar mix made especially for "decks", meaning tile decks. Using that will be easier than mixing your own from cement and sand, and more reliable. Mix it stiff; it should hold together when you squeeze it into a ball, but should not squeeze through your fingers. The mortar in the base will be thicker than at other points so far, so mix it with water, not additive. Set a layer of mortar in the shower base and screed it enough to approximate the 1/4" in one foot slope; this layer should be about half that needed. A wood float is a good tool for this step. Lay wire mesh or expanded metal on that and continue with the rest of the mortar. The inner level of the mortar at the drain should be below the top of the drain by the thickness of the tile and thinset, and the outer level of the mortar bed should be right up against your masking tape marker. You may want to use a steel float for this finishing. Compact the mortar with the float and check to be sure it is flat and sloped correctly. Very critical step; what you end up with here will determine the surface level of the tile. Note that we have not completed the top of the curb.
      After the base mortar has set overnight, remove the masking tape and tile the base. Proceed from there up the walls and inside the curb with the first row of tile. Take pains with the level of the TOP of this bottom row because it will set the stage for the rest of the walls. You will probably have to trim tiles so the top comes out level.
      Now tile the outside face of the curb. When doing this check with a level across the outside and inside tiles to be sure there is an inward slope, and trim the bottom row of tiles so you have full tiles in the top row. Typically the top of the curb is covered with two rows of bull nose tiles; one row to the inside and one row to the outside, and these will probably have to be cut and joined in the middle. Same for the sides of the opening. The shower door is set over the joint between the two rows of tiles. If the gap between the level of these tiles on the curb and the pan over the top of the curb is deeper than about 1/4", partly fill it with thinset, leaving enough space for the layer of thinset holding those tiles on the curb.
      Where you have a tile backerboard meeting drywall - like outside a shower or tub area - leave a small gap and caulk with butyl rubber or polyurethane caulk. If you plan carefully, the tile can slightly cover that caulked joint to hide it. When the tiling is completed, caulk the edge of the tile to the drywall with latex tub and tile adhesive caulk. Don't substitute silicone caulk anywhere; it is near impossible to get a reliable joint with it.

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