Tile Installation Questions, Answered

Tile needs a rigid, stable surface. The standard threshold for floor deflection is L/360, meaning the floor should deflect no more than the span divided by 360 under load. On most residential joisted floors, that means we may need to add cement backer board, a self-leveling compound, or in some cases additional blocking beneath the subfloor. We check this during the walkthrough before we give you a price.

Both are kiln-fired clay products, but porcelain is fired at higher temperatures and uses a denser clay body. The result is a water absorption rate below 0.5% for porcelain versus up to 3% or more for ceramic. That makes porcelain the better choice for wet areas like showers and mudroom floors. Ceramic costs less and is easier to cut, which can make it practical for low-traffic backsplash work where moisture is not the main concern.

Yes. We typically recommend ordering 10% more than your square footage calculation, and 15% more if the layout involves a diagonal or herringbone pattern. Cut tile at perimeter walls, around obstacles, and at doorways adds up quickly. It also gives you a match for any future repairs. Tile dye lots change between production runs, so the box you buy today may not match one ordered two years from now.

A shower surround on an existing, structurally sound substrate typically takes two to four days for the tile work itself. Add a day for waterproofing cure time before tile goes up, and another day or two for grout cure before the shower can be used. A full bathroom floor and wall tile project with a tub surround can run five to seven working days depending on size and layout complexity. We give you a timeline estimate during the walkthrough.

A mortar bed, sometimes called a mud bed, is a layer of Portland cement mortar floated over the substrate before tile is set. It is used when the existing surface is significantly out of level, when a custom-sloped shower pan needs to be formed, or when the substrate is not appropriate for direct tile setting. It adds time and cost but creates an ideal, permanent base. Modern uncoupling membranes have replaced mud beds in many residential applications, but for shower pans with complex slopes, a mud bed is still the most reliable method.

Grout contains Portland cement, which lightens significantly as it cures and moisture evaporates. What you see in the bag or in a wet application can be two or three shades darker than the finished result. We always show clients a cured sample before committing to a color on a large installation. Epoxy grouts, which we sometimes use in commercial or high-moisture applications, behave differently and tend to hold their color more consistently.

Most cement-based grouts do benefit from sealing, particularly in wet areas and on floors where foot traffic and spills are common. The sealer penetrates the porous grout surface and slows moisture and stain absorption. It is not permanent and needs to be reapplied periodically, typically every one to three years depending on the product and the amount of use the surface gets. Epoxy grout does not require sealing. We discuss sealing as part of the closeout walkthrough on every job.

The most common causes are inadequate mortar coverage behind the tile, a substrate that was not properly prepared or was still moving, and the absence of expansion joints in large installations. Tile and mortar do not flex. When the structure underneath moves seasonally or under load, without expansion joints to accommodate that movement, stress concentrates at the bond line and eventually breaks it. This is why we assess the substrate before every job and include expansion joints in large floor installations per TCNA guidelines.