Calculating allowable tile lippage
At the beginning of this article, the author stated allowable lippage is either 1 or 2 mm (1⁄32 or 1⁄16 in.), depending on the tile and the width of the grout joint, in additional to the inherent warpage of the tile manufactured in accordance with ANSI A137.1. Tile Council of North America (TCNA) interprets this in its 2014 Handbook for Ceramic, Glass, and Stone Tile Installation as meaning the inherent warpage of a particular tile is the actual warpage the specific tile has when installed.
Some people incorrectly interpret this to mean they can take the maximum allowable warpage stated in ANSI A137.1 and add it to the respective allowable lippage value. However, this author believes the calculated lippage would be unreasonable and excessive from a standard-of-care point of view for professional tile installations.
Installation methods
The tile installation method can help limit lippage or contribute to its excessiveness. Adhering the tile directly to the substrate, particularly when it has not been properly prepared to meet the industry requirements for flatness, can make it difficult to avoid lippage. On the other hand, installing tile in a fresh dry-pack mortar bed while it is still in a plastic stage can help compensate for dimensional variations because the installer can embed it into the fresh mortar.
Another contributing factor is the skill and craftsmanship by the tile installer. When workers are not sufficiently experienced, skilled, or detail-minded, their poor workmanship can cause or contribute to excessive tile lippage. It is important qualified, skilled installers who understand current industry standards are used for tile and stone installations to help ensure a successful installation.
Unavoidable lippage at drains
There are some applications where tile lippage to some degree is unavoidable. ANSI A108.02-2013 Section 4.3.7 cautions the lippage requirements do not apply to tiled floors sloping to drains specifically when using tiles 15 x 15 mm (6 x 6 in.) and larger. The larger the tile surface area, the greater the potential for tile lippage under these conditions. This is why one often sees tiles cut in half at a diagonal near drains with sudden changes in slope. However, this does not mean the installer can have extreme tile lippage—it still needs to be reasonable considering the conditions.
Using relatively new trench or linear drains for tile installations can be a good solution to avoid this problem. The trench or lineal drains can be installed at the perimeters of decks or showers. The trench drains can be installed so the tile or stone is attached to the center, enabling it to blend within the flooring, allowing drainage around the tile edges and avoiding lippage in these locations.
Perception is reality?
Sometimes, excessive tile lippage is perceived by end-users despite everything being within allowable standard tolerances. The culprit is lighting. Even the best of tile installations can look awry when the light is shining on the surface at a certain angle relative to the one from which it is being viewed.
This is more problematic with large, rectangular tiles with narrow grout joints installed on walls, particularly in a staggered pattern. At certain angles and in the right sunlight, some tile exterior veneers look like there are built-in handholds to climb up the wall, despite lippage actually being within tolerance.
This is because lighting causes shadowing at the grout joint, creating an optical illusion. (This can also occur in interior applications with daylighting or electrical systems.) TCNA’s Handbook for Ceramic, Glass, and Stone Tile Installation warns use of wall-washer and cover-type lighting—where lights are located either at the wall/ceiling interface or mounted directly on the wall—may produce shadows and undesirable effects with tiles.
Similar shadows are created from side-lighting interior walls and floors when light shines from an angle through windows and doors. This author has investigated many commercial and residential projects where there were complaints of alleged excessive tile lippage only to find out during the inspection it was reasonable and within allowable industry tolerances. Of course, there have been numerous other cases where there actually was excessive lippage because the contributing factors listed throughout this article were not properly managed.
I’ve noticed that in some homes I’ve been in, that there is significant lips on the edge of tiles. I do think it is important that there is a slight lip, but nothing too big. Having one too big would be a home for dirt and other things to get caught in. Just be sure if you are doing something like this yourself, that you do it to the proper specifications.
Good take on what is acceptable and what isn’t with tile lips. I think a slight lip is great but it’s easy to go overboard. Thanks for sharing.
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What percentage of floor tiles that are at the 1/32″ limit for lippage, is acceptable? In 340 Sq. ft. we have 40 spots that are at 1/32″ lippage and 8 spots that are above. I have yet to see the percentage question addressed. Imagine a floor where all tiles are at 1/32 lippage. Would it technically be acceptable? With the above specs our floor looks terrible. we can”t even push our kitchen chairs under our table without having to lift them>
I have the same issue..exactly the same! I know this is an old post, but please share if you received a reply to your question. Thank you in advance.
My Question is similar to Mike B.’s. I have a 2000sqft house that is tiled throughout. Nearly each tile has at least one adjacent tile that is uneven (i.e., there is lippage throughout the house) and I would be hard pressed to find a tile with an no lippage. The RESIDENTIAL PERFORMANCE STANDARDS GUIDELINES states: “…Lippage greater than 1/16″ is considered excessive…except where…tile [is] larger than 13 × 13 inches.” My tiles are about 20″. For me, it is not that there is lippage, but the fact that there is lippage THROUGHOUT the house. What is the corrective measure for this?
I also have the similar problem. Any inputs in this matter are highly appropriated.
There is no percentage of tiles with lippage in excess of the ANSI standard stated. I guess the installers are expected to complete the job with no lippage beyond what is allowable. This is the same as other floor covering categories. Manufacturers have a realistic 5% error rate but installers, as the final quality control step, have no acceptable error rate. They could always follow the NAHB performance guidelines which are more forgiving for imperfect situations.The NAHB, as stated by Mark S. does not even list an acceptable lippage measurement for tiles larger than 13″. Maybe whatever lippage is present is acceptable to them? As stated in the article, there are usually several contributing causes for the final lippage.
There are tiles that are sunk in lower that the adjacent tile. What is the remedy to laying them even. We would like these tile removed and reinstall. Is it possible if tile is pulled it will make the floor weak and the other tiles may become loosen. So disappointed in the overall job. About 20% of the floor has lippage.
You are joking right when you fix a tile bigger than 600 mm long they don’t make them straight so you will always get lippage if you want no lips buy a vinyl floor
Buy he way 3 mm is the industry standard in the uk
I have an 80 square foot bathroom set with 12” by 24” porcelain tiles. The first tile job was ripped out because the lippage was severe among other problems. The second installation I still think is not right. When two tiles are next to each other i expect them to be smooth when I run my hand from one to the next. The contractor laid a credit card down on a tile edge where there was Lippage and once the card was pushed against the next tile the adjoining surfaces where smooth. I expect all the tiles to be laid like that. He said the credit card differential was acceptable with some tile industry standard but if it is not acceptable to a customer how can they make that excuse? I don’t know what to do or who to trust.
Tile is not perfect. Tile is not square. The same tiles in a box are not all the same size that is why there is an ANSI standard so the contractor can sue you for his money if it comes within the standards. You cant make a tile job perfect since tile is not made perfect. Just use common sense about the amount of lippage there is. Some home onwers are just cheap and dont want to pay and some tile setters are hacks. The card trick is a good way to check lippage for a commercial job. In residential, home onwers are more picky and expect more perfection so the contractor should bid accordingly, knowing how most home owners are with expectations. That is why I stopped doing residential.
If you expect/want no lipage plan to purchase an excessive amount of tile.
I’m having the same battle with KB Home. I paid for an upgraded rectified Emser tile with zero discernible warpage. They laid every single tile 7/32 to 9/32 averaging 1/4 grout line with zero tile warpage. One quarter of the 900 SF area has lippage that exceeds or surpasses 1/16. They are trying to kus replace the tiles in questions but when they replace them adjacent tiles become the problem.
There’s an arrow on the back of most floor tile. Point the arrow in the same direction as the others and there’ll be no 👎lippage.
I have a few areas of tile Lippage in a newly laid kitchen with large format 9×47 non-rectified tiles. There is one area in particular that although to the eye is not bothersome I can really feel under my feet. Am I better off leaving this alone..can it do more harm than good replacing a tile on an already grouted floor? I know it shouldn’t be acceptable, but should I just leave well enough alone if it looks good?
I should add that the Lippage is about a “quarter” high in the areas I speak of.
Fran. I have a similar issue. Did you ever get an answer? Or did you just leave it alone?
Isn’t there a term for intentional tile lippage as to give tiled surfaces a rustic effect
Do these lippage requirements apply to travertine or limestone around a pool outside?
I would hope so, since the tripping hazard is potentially fatal, however I understand that outdoor is a different set of conditions. Just wondering what is acceptable outside when the stones are first laid.