In this guide

Floor Measurements

To get the most accurate costs and to ensure that you have enough tile to complete the installation, the first step is to measure your floor. Porcelain tile is sold by the square foot, with most types of tile being sold by the box, meaning that you need to round up to the nearest full box of material.

To measure your floor, measure the length and width of the room in inches. If there are jogs or bump-outs along the walls, measure each section separately in inches. Multiply the length and width of each section together and divide by 144, the number of square inches in a foot. This will give you the total number of square feet of the space. Add up each of the different areas to get the total square footage of the area you are tiling and round to the nearest whole foot.

Keep in mind, that for a straight-set porcelain tile installation, you will need an additional 5% to account for waste, cuts, or breakage. If you intend to install the tile on the diagonal or in a pattern, you will need a minimum of 20% extra. It’s always a good idea to have some extra tile on hand for the future in the event of a breakage or repair job, so always round up to the next nearest box size, not down.

Subfloor

Porcelain tile is fairly easy to install over any level subfloor ¹. If your subfloor moves or shifts, or if it isn’t level, then a concrete backerboard is generally installed first, then the porcelain tile is installed over it. Backerboard costs around $5 per foot.

If your subfloor is in good condition, but not entirely level, it is possible to use a self-leveling floor compound over the subfloor, beneath the porcelain. Self-leveling floor compound is poured onto the subfloor, where it seeks out highs and lows and levels them. The compound costs around $40 per bag, with this generally covering at least 200 square feet.

Pros and Cons

Porcelain tile makes a great, low-maintenance option for many floors, but it isn’t always right for every application.

Pros

• Porcelain tile is non-porous, durable, scratch resistant, and freeze/thaw resistant.
• It can be cleaned with anything and does not require sealing or special maintenance or care.
• Porcelain can be made to mimic the look of many other materials, including stone, metal, fabric, and glass, as well as wood.
• It comes in many styles and sizes, so finding one that can suit your decor and needs is simple.

Cons

• Porcelain tends to be more expensive than ceramic, with average costs starting at $5 per foot. More exotic and large format porcelain tiles can go as high as $30 per foot.
• Glazed porcelains may be slippery underfoot, although not all porcelain is glazed. Because the material is non-porous, polishing or glazing can create a very slick surface that can be difficult to walk in in certain shoes or in certain conditions.
• Porcelain can be very difficult to cut, and requires a diamond wet saw and sometimes cooling oil.
• Large format porcelain may require backbuttering to install properly, which can increase installation costs.

How to Choose the Right Tile

Like many floor coverings, the porcelain tile that you ultimately will choose for your home will depend largely on your personal tastes. However, there are a few guidelines that can help you narrow down your choices:

• Look for the largest-size tile that a room can comfortably hold, particularly in small spaces, to make the room look larger
• Opt for mosaics of 2-inches or smaller in areas such as showers or where you need a non-slip floor, or where the floor may not be evened out easily, such as areas that slope to a drain
• Avoid porcelains that have metallic glazes in kitchens, as things like acid can etch or harm the finish
• Look for highly-textured or variegated finishes for high traffic areas, such as mudrooms to help hide dirt and to increase slip resistance
• Look for tiles that are a minimum of ⅜-inch in thickness to increase durability
• Look for tiles that are rectified or that have been machined on the edges to decrease the size of your grout ² joints.

Characteristics

Porcelain tile is often confused with ceramic, as both are made from clay. However, porcelain has a set of characteristics that vary tremendously from ceramic and other materials.

• PEI: porcelain’s PEI or Porcelain Enamel Institute rating ranges from a 4 to a 5, depending on the manufacturer and the surface texture.
• COF: porcelain’s COF or Coefficient of Friction rating is a minimum of .6 or higher, with .42 being the lowest acceptable rating for indoor tile.
• Texture: porcelain can be very smooth and ground to a high-gloss finish, or it can be very high textured. Porcelain can be given a glaze to have it mimic the look of other materials such as wood, fabric, or metal as well.
• Cutting: porcelain tile is very dense and hard to cut with nippers. It cannot be cut using the score and snap methods and requires the use of a tile wet saw.
• Use: porcelain is suitable for use indoors and in exterior applications, and is not affected by freeze/thaw conditions.

• Density: porcelain has a breaking strength of more than 450 pounds of pressure per square inch - higher than even high-density ceramic tile.

• Water absorption rate: porcelain’s water absorption rate is less than .5%, meaning that it absorbs very little water.

• Price: porcelain’s average price is around $5 a square foot, but can go as high as $30 a square foot for some luxury tiles.

Designs

Because porcelain is available in so many different sizes and shapes, it is possible to install it in a variety of different patterns and designs. These include but are not limited to:

• Straight set
• Diagonal
• Running bond
• Herringbone
• Stacked brick
• Versaille (five piece pattern)
• Step pattern
• Oct-and-dot
• Basketweave
• Cut corners and dots

Porcelain tile itself can be fashioned to mimic a wide range of different materials, giving it a variety of other appearances and styles. You can find porcelain with designs such as:

• Polished marble
• Textured slate ³
• Woodgrain
• Tumbled stone
• Glass
• Woven fabric
• Metal

Porcelain also comes in solid-colored tiles in a range of sizes in polished, matte, and textured finishes.

Labor

In many ways, installing porcelain tile is like installing any other tile. The substrate should be clean and level ⁴, free of any debris or movement when pressed. If necessary, new concrete backerboard should be mortared ⁵ and screwed down to the existing subfloor ¹, or a self-leveling floor compound poured over the existing flooring.

The average cost of labor for tile installation is around $4 per square foot ². For intricate patterns or severely unlevel floors, this price could rise as high as $7 per square foot.

Sealing

Porcelain tile is non-porous with very low water absorption. Therefore, it does not require sealing to impede staining the way stone or crazed ceramic tiles do.

However, if you are not using a pre-sealed or epoxy-based grout ² with the tiles, your grout should be sealed. And, if you find that your porcelain is slick underfoot, some types of sealers, such as Miracle Sealants, can increase traction and slip resistance on porcelain tiles as well. Sealing will not change the appearance of the feel of the tile.

Maintenance

Porcelain is one of the easiest flooring materials to care for. It doesn’t stain or scratch and it doesn’t require special cleaners. Sweep up debris as necessary, and mop with your favorite floor cleaner. If the grout ² stains, you may want to consider sealants for this area, otherwise there is no specific maintenance involved in porcelain upkeep.

Marble vs Porcelain Tile

Porcelain tiles may be created to mimic the appearance of marble as well as other natural stones. Porcelain may also be polished to a high-gloss finish that is reminiscent of marble. However, the two materials are very different in terms of makeup and maintenance.

Marble is a natural, metamorphic stone made primarily of calcite. It can stain, scratch, and etch and requires sealers and the use of PH neutral cleansers to maintain its appearance. Because marble is porous, it is actually less slippery than porcelain, even when polished. And because of those pores, the appearance of a polished marble tile will not be quite as reflective as the appearance of a polished porcelain tile.

Both marble and porcelain tiles can be found in many sizes, finishes, and colors. Both can be bullnosed on site. Marble should not be used in steam showers or very wet areas, as it may stain; porcelain can be used in these areas without any issues.

Marble costs begin around $5 per foot, with an average cost being between $9 and $24 per foot, higher than the cost of porcelain

Porcelain vs Ceramic Tile

Both porcelain and ceramic tile are made from clay, and both can come in many different styles and finishes. The comparison ends there, however. While porcelain is made from compressed clay dust that has been fired to high temperatures, ceramic tile is made from extruded wet clay fired to lower temperatures. Ceramic tile may be fired once - monocottura, or twice - duocottura. Duocottura and high-density ceramic tiles have lower water absorption and better strength, but are still more porous and weaker than porcelain tile is.

Not all ceramic tile can be used on the floors; many ceramic tiles are rated for wall or counter use only, while all porcelain tiles can be used on either the walls or the floor.

The biggest difference in appearance between the two has to do with the top surface. Ceramic tile is always glazed, while porcelain tile may have a color-through clay body or it may have a glaze, and in some cases both. Ceramic tile cannot be bullnosed on site and must use a separate bullnose tile to complete the edges of installations. Ceramic tile costs begin at less than $1 per foot ² but can go as high as $30 per foot ² for some handmade tiles.

New Installation vs Replacement

Even the strongest tiles sometimes need replacement. For example, if you are having work done in a bathroom a leak causes some of the tiles to come loose, you may need to replace them. This is why it’s best to have some extra or additional tiles on hand from the original installation; it can be difficult to match the dye lot from older tiles to newer ones even from the same manufacturer.

Porcelain tile is fairly easy to replace. It can be removed with a chisel and a pry bar, and the old mortar ⁵ chiseled out down to the subfloor ¹.

If more than a few tiles are being replaced, however, your costs will go up considerably as the cost to remove the old floor will need to be factored in. Old porcelain floors are removed by chiseling or breaking the first tile in a row, then inserting a pry bar beneath the edge of the surrounding tiles and pulling them loose. A floor scraper is used to remove the old mortar from the floor before the new tile can be put down. You can expect this tearout to increase costs by about $1 to $2 per foot, or you can handle the tearout yourself to save the difference.

Enhancement and Improvement Costs

Removing Old Floors

If you need to remove the old floor first, your costs will be higher than if you are tiling directly onto another material or a subfloor ¹. The cost to remove the old floor can vary tremendously, though, based on what is already installed. Some very old vinyl ⁶ floors contain asbestos ⁷, for example, while old linoleum ⁸ glue gets stronger as it ages, making it hard to pull up. For a 200 square foot tile installation, your costs could range from $200 to $2,000 depending on what you are having removed.

Remodeling Terms Cheat Sheet

¹ Subfloor: The bottom-most layer of a floor, supported by joists, over which finished flooring material is laid

² Grout: A fluid form of cement used to seal the joints between tiles. It also makes the surface stronger because it bonds the tiles together

³ Slate: A fine-grained rock, typically bluish-gray in color, that can easily be split into thin layers and is commonly used as a roofing material

⁵ Mortared: A mixture of Portland cement or lime or a combination of both, sand, and water used to bind bricks, stones, and concrete masonry units together

⁶ Vinyl: A synthetic plastic made from ethylene and chlorine. Vinyl has many applications in the construction industry and it is widely used in sidings, window frames, roofing and gutters, among others

⁸ Linoleum: An inexpensive flooring material made from linseed oil, resins, recycled wood flour, cork dust, limestone and mineral pigments, on a canvas or jute backing.