How to Estimate Tile Quantity

Kitchen Tiles
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When doing your own tile work, it is necessary to make sure that you have enough tile on hand to complete the job. It’s a disheartening thing to run out of tile on a Sunday afternoon with the tile store being closed.

Yet you do not want too much tile. Even though most tile stores will accept returns, you never want to lay out more cash than is needed. Also, having too much tile on hand raises the possibility of damaged tile, which cannot be returned, or of simply cluttering your workspace with unneeded materials.

So it is best to carefully estimate the quantity of tile needed for the project. The basic idea of any estimating job, particularly tile work, is to estimate a little bit more than is needed.

Size and Shape

The main factors that come into play are the size and shape of the tile, the spacing between the tiles, trim, and how complex your tile design will be.

For example, as you are aware rooms are typically square or rectangular in shape. Therefore, tiles which are square or rectangular fit best into these rooms and result in less wasted tile. So if you have irregularly shaped tile, such as octagonal tile, then you will have more wasted tiles. Conversely, oddly shaped rooms created more wasted tiles. And within both types of rooms, unconventional layouts, such as adding angles or working around many obstacles, will result in more wasted tiles.

Estimate tiles based on their type: field or trim.

Field tiles are the tiles that comprise the main area of the room. Trim tiles are those linear decorative tiles that finish off the field tiles.

Field Tiles

  • For every measurement that you determine, nudge that measurement on up to the next foot. For example, if you have measured 12 ½ feet, move that measurement up to 13 feet.
  • Figure in the width of the grout joint in addition to the area of the tile itself. This may seem like “overkill,” but it is surprising how much the area grout joints will eat up. Grout joints do not look very big, but when multiplied hundreds of times over, they do constitute a significant amount of tile real estate.
  • Tiles which are pre-mounted on sheets already have grout spacing in them. So just measure the outside dimensions of the entire tile sheet.
  • Providing that you have measured and calculated correctly, add 10% on to that number. For example, if the calculated area is 100 square feet, bump that number up by 10%, resulting in 110 square feet. However, if you are working with tiles which are not square or rectangular, add 15%.

Trim Pieces

Trim pieces are different from field tiles because they represent linear feet, rather than area. Because trim pieces can often be extremely expensive, you may want to measure these very carefully. Measure the length with a measuring tape, and add 15% to the number.