Installing tile flooring to your home is a good way to add character to a room while increasing the durability of your floors. While the preferred method of tile installation once was to create a thick mortar bed, many professionals today place a cement backer board over an existing plywood subfloor. Cement backer boards are durable and inexpensive, costing around  $12 per ½-inch thick, 3 x 5-foot sheet.

    Putting in tile as a DIY project is a way to save on remodeling and home improvement costs. If you want to update the floors in your kitchen, bathroom or other room of your house, you can start by prepping your subfloors appropriately.


    Prepping the Plywood Subfloor

    The first step to tile installation is to prep the plywood subfloor. Expose the subfloor by removing the carpeting or other current floor covering. Then make a thorough inspection of the subfloor and make appropriate repairs. Common subfloor issues include: 

    • Damaged or sagging areas, which will require replacement plywood 
    • Exposed seams that need caulking
    • Uneven sections that require sanding 

    Past leaks from nearby tubs and showers can also damage the plywood. Significant water damage may require more extensive repairs than just replacing the subfloor. 

    Once your subfloor is sound, you can lay down the cement backer board.


    Installing the Cement Backer Board

    Proper installation of the backer board is key to creating a durable underlayment for the tile. When estimating the amount of board you will need for your project, remember that you will want to leave ¼-inch gaps between the board sheets and walls to allow for subfloor movement.

    Many cement backer board brands, including Durarock and Permabase, provide installation instructions, but in our experience there are a few industry-wide best practices. Cut the cement backer board with a carbide-tipped saw, then score and snap the boards along their cut lines. Wear a respirator and goggles during this process for protection. 

    Next, use a notched trowel to spread thinset adhesive on the plywood subfloor. While the adhesive is wet, set the backer boards and secure them with corrosion resistant screws that are appropriate length for the plywood thickness. Most manufacturer spacing guidelines recommend placing screws every 8 inches. 

    After sinking all screw heads and existing nails use a lightweight joint compound to fill in any gaps or low spots. Taking care in this step is essential to ensure that the installed tile will not crack. Finally, seal any seams and corners between the backer boards with joint tape and thinset to prevent moisture penetration. 


    Use a cordless drill to screw cement backer board to a plywood subfloor.
    Image Credit: Canva

    Laying the Tile

    Now you can lay out your chosen tile design. Spread thinset adhesive on the backer board and set the tiles, leaving â…›-inch gaps to account for expansion of the grout. You can use spacers to help with this process. 

    Work in small sections and firmly set the tiles by tapping them with a rubber mallet, if needed. Once you set the tiles, you can grout the tile joints with a damp sponge, and wipe away any excess. Finally, apply grout sealer for additional protection. 

    In our experience, it is best to avoid using grout when placing tile near tubs, cabinets, or walls. This is because the grout will crack when these areas contract and expand. Leave at least ¼-inch gap between tile flooring and walls to prevent this issue and use flexible caulk in these areas instead, so that the joint remains functional. 

    Tile Installation Cost

    Depending on the materials used, your region, and the project’s intricacy, the cost of tiling professionals ranges from $5 to $45 per square foot.  DIYers can save on these project costs substantially, as tile and setting materials cost $3 to $5 per square foot on average.


    laying tile
    Setting tile on cement backer board with spacers used to align the tile.
    Image Credit: Canva

    So, Is Installing Tile Over Wood Floors a Good Idea?

    In our experience, tile can be a great upgrade to worn vinyl or carpet floors. This is because tile is durable, waterproof and easy to clean. When you prep the subfloor properly and use quality materials, the resulting project can last decades. 

    In addition, installing tile yourself can result in big savings over a professional job. However, it is important to do your research beforehand and learn the proper techniques. 


    FAQs About Installing Tile Over Wood

    What are signs the subfloor needs repair?

    Soft spots, uneven areas or visible water stains may indicate that your subfloor is rotting. You also want to check for loose boards during installation and press down on any boards near walls to see if they squeak.


    Can I use greenboard instead of cement backer board?

    In our experience, greenboard is one of the surfaces not to put tile on because it lacks durability. Cement backer board is a much better choice.


    Should I use a membrane under the tile?

    Membranes are recommended for larger tile projects to help prevent cracking. For smaller tile formats, cement backer board is fine to use.


    How long does tile adhesive take to cure?

    Thinset dries in six to eight hours. For this reason, we have found that it is best to wait 24 to 48 hours before grouting, and avoid heavy use of your new tiled floors during this time frame.


    Can I use leftover thinset?

    It is fine to reuse leftover thinset if you seal and store it properly. You can add fresh powder to the existing product and mix it well. Do not add water to the thinset as this will weaken the mortar.


    Should sanded or unsanded grout be used?

    It is best to use unsanded for joints under ⅛ of an inch and use sanded grout for wider joints up to ½ an inch.  You can also use polymer-modified grout to improve the durability of your project. In any scenario, match the grout color to your tile.


    Editorial Contributors
    avatar for Nikki Stavile

    Nikki Stavile

    Nikki Stavile is a writer based in Tucson, Arizona. As an avid backpacker and passionate environmentalist, her work often focuses on sustainable movements at the personal and societal level.

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    Sabrina Lopez

    Editor

    Sabrina Lopez is a senior editor for Today’s Homeowner with over 7 years of writing and editing experience in digital media. She has reviewed content across categories that matter to homeowners, including HVAC services, home renovations, lawn and garden care, products for the home, and insurance services. When she’s not reviewing articles to make sure they are helpful, accessible, and engaging for homeowners like herself, Sabrina enjoys spending time with her family and their two parrots.

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