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.
Ceramic tile lippage standards.
Lippage is the vertical displacement between two adjacent tiles of a ceramic glass or stone installation.
Some types of tiles also curve as much as 0 5 the length of the tile such as polished porcelain tiles.
Too narrow grout joints.
This is assuming that the warpage of the tile is within the standard s acceptable range for that type of tile.
Long narrow tiles are used.
Rectangular tiles are harder to lay flat.
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.
Some joints are 1 8 others are 5 8 with a lot of lippage some even at 6 credit cards deep.
I just had a complete remodel of my bathroom contractors are using 12 x 24 porcelain tiles.
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.
They are telling me it is within the standard based on the tile warpage.
A bad batch of tiles tends to show lippage more.
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.
American national standards institute ansi a108 02 2013 general requirements.
Variation in the height of adjoining tiles is called lippage.
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.
It states for grout joints that are less than 6 mm 1 4 in wide.
When excessive this can lead to numerous problems ranging from chipped edges to snagged furnishings and appliances to safety hazards.
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.
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.
There are tolerances for tile lippage.
The allowance for such warpage is also spelled out in a137 1 and would apply if your tiles are advertised as meeting that standard.
Narrow grout joints may look pleasing to the eyes but it increases the chance of tile lippage.
