A bad batch of tiles tends to show lippage more.
Ceramic tile lippage standards.
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.
They are telling me it is within the standard based on the tile warpage.
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.
The allowance for such warpage is also spelled out in a137 1 and would apply if your tiles are advertised as meeting that standard.
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.
Narrow grout joints may look pleasing to the eyes but it increases the chance of tile lippage.
Rectangular tiles are harder to lay flat.
Variation in the height of adjoining tiles is called lippage.
Long narrow tiles are used.
Lippage is the vertical displacement between two adjacent tiles of a ceramic glass or stone installation.
This is defined in the ansi american national standards institute standard a108 02 section 4 3 7.
Some joints are 1 8 others are 5 8 with a lot of lippage some even at 6 credit cards deep.
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.
Too narrow grout joints.
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.
American national standards institute ansi a108 02 2013 general requirements.
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.
It states for grout joints that are less than 6 mm 1 4 in wide.
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.
There are tolerances for tile 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.
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.
This is assuming that the warpage of the tile is within the standard s acceptable range for that type of tile.
Some types of tiles also curve as much as 0 5 the length of the tile such as polished porcelain tiles.
