Ceramic Tile Lippage Standards
This is assuming that the warpage of the tile is within the standard s acceptable range for that type of tile.
Ceramic tile lippage standards. The ansi a108 02 standards say that acceptable lippage for floor tiles with a grout joint width of 1 16 to less than 1 4 is 1 32 plus the allowable inherent warpage of the tile. If the grout joint width is 1 4 or greater then the allowable warpage is 1 16 plus the allowable inherent warpage of the tile. I just had a complete remodel of my bathroom contractors are using 12 x 24 porcelain tiles. For large tiles exhibiting the maximum allowable warpage 50 offsets are guaranteed to exhibit lippage.
To address this on a practical basis some manufacturers recommend against any patterns with offsets in excess of 33 if the tile being used has an edge larger than 18 inches. It states for grout joints that are less than 6 mm 1 4 in wide. There are tolerances for tile lippage. For your tile size and joint width presuming no offset the maximum allowable difference in elevation between tiles lippage is 1 32nd of an inch in addition to the inherent warpage of the individual tiles.
The standards state that a tile with a grout joint that is less than wide can have 1 32 of lippage in addition of what the actual warpage is of the tile being installed. Rectangular tiles are harder to lay flat. When excessive this can lead to numerous problems ranging from chipped edges to snagged furnishings and appliances to safety hazards. A bad batch of tiles tends to show lippage more.
Today however the ceramic tile industry has grown far more complicated as 12 in by 24 in 18 in by 18 in 24 in by 24 in and larger tiles are manufactured in abundance. Materials environmental and workmanship section 4 3 7 lippage guidelines explanation and caution deals with what is allowable ceramic tile lippage and how to avoid excessive lippage. Long narrow tiles are used. When the specification for ceramic tile american national standard was first revised in 1988 large format tiles were 8 in by 8 in and 12 in by 12 in.
This is defined in the ansi american national standards institute standard a108 02 section 4 3 7. Lippage refers to differences in elevation between edges of adjacent tile modules the ansi standard notes that the perception of lippage is influenced by many factors such as. Too narrow grout joints. Lippage is the vertical displacement between two adjacent tiles of a ceramic glass or stone installation.
Some joints are 1 8 others are 5 8 with a lot of lippage some even at 6 credit cards deep. Narrow grout joints may look pleasing to the eyes but it increases the chance of tile lippage. They are telling me it is within the standard based on the tile warpage. Variation in the height of adjoining tiles is called lippage.