#MAPEITechTip: Tile ‘Lippage’—‘mechanical lippage tuning systems’ to the rescue!

If you have been around the tile and stone industry for any length of time, you will remember when 12”x12” was considered large format tile and 6”x 6” glazed ceramic tile was the design of choice for most bathroom walls.  Nowadays, really all bets are off as to tile size, texture and design, especially now that thinner (1/8” (3mm) to 1/4” (7mm)) larger format tiles are becoming the norm—with some up to 5’ x 10’ in a single tile panel!!!
 
With the increase in format size, it has required us to re-think how we install tile, including using large and heavy tile mortars (formerly medium-bed mortars), better surface preparation to 1/8” -10’ (FF of 50) for floors and plumb and flat walls, and new to the market, ‘mechanical lippage tuning systems’.  You may be wondering what is ‘lippage’ and why is it more of a concern than it was years ago? In a word, larger format tile that is thinner, with grout joints that are 1/16” if we are fortunate.  Add to this surface preparation (walls or floors) that is inadequate for larger and larger tile sizes (ANSI A137.3-2017;Gauged Porcelain Tile and Gauged Porcelain Tile Panels/Slabs) inconsistencies in tile size or flatness, mortar sag and/or shrinkage, installing tiles with the ill-fated ‘spot-bond method’—all of these variances in a single tile installation are known as ‘the accumulative effect”. This effect accentuates any defects in the tile installation—often being manifested as ‘lippage’. ‘Lippage’ (ANSI A108.19-2017; "Maximum allowable lippage is 1/32" / 0.8mm) is very noticeable either on the wall or floor, leaving one edge of an adjacent tile higher than a neighboring tile, causing an uneven appearance to the finished surface.

Safety Issue:  Excessive ‘lippage’ can lead to damaged tile edges as people, carts and other objects move over the tile repeatedly hitting these ‘higher’ unsupported tile edges. It can also cause trip-and-fall incidents, in high-traffic areas or commercial settings, particularly with younger or older customers. Often once the tile is installed and set, the only way to correct a floor with excessive ‘lippage’ and potential trip hazards is to grind down the tiles, weakening the tile structure and causing an aesthetically displeasing tile installation.  Making for some very unhappy customers….

Lighting Effect on Walls & Floors: Lighting and positioning of the lights can either aggravate or minimize the effects of ‘lippage’ on a wall installation.  When natural or man-made light shines on walls at an angle, where it is parallel to the tile surface, any lippage (acceptable or otherwise) is highlighted and accentuated by the light and angle. It can take an otherwise professional tile job into the realm of anything but real quick. 
 
For many years, tile industry professionals have been well aware of the uncontrollable effects of “wash lighting” on tile walls. In the fields of interior design and lighting design, two specific terms are used to describe the effects most commonly produced from wash lighting. Wall grazing is a lighting condition meant to highlight and enhance changes in texture and depth, producing dramatic shadows and emphasizing variations.  Wall grazing is most commonly used to accentuate walls made of brick or stone. It can be a tile installer’s nightmare, taking the smallest of imperfections or irregularities and highlighting them, causing the entire installation to look like a poor quality tile job.
 
‘Wall washing’ is a lighting condition meant to smooth out rough uneven surfaces, reduce the appearance of texture and produce a soft non-glare illumination. Lighting fixtures are placed 3 to 4 feet from the wall and evenly from each other. Florescent lighting, and low voltage incandescent lighting can be used to produce this effect. Wall washing minimizes imperfections and minor irregularities in tile installations, giving the impression of a flat, level, and neatly tiled wall.

How can ‘mechanical lippage tuning systems’ help in reducing ‘lippage’?  These systems are designed to create a virtual lippage free installation when used on floors or walls—by interlocking the tiles, creating a single flat, monolithic slab surface while the setting material is curing. The interlocking design of the system reduces and in most cases eliminates settling from shrinkage, as well as minimizing the effect of warping. The system reduces the need to re-lift tiles to add more mud and/or the process of shimming tiles; thus greatly increasing the speed of installation, all the while creating that much desired lippage free mirror surface. In addition, the caps are reusable dozens of times.

'Mechanical lippage tuning systems' are strongly recommended (ANSI A108.19-2017 "When installing multiple gauged porcelain tiles or gauged porcelain tile panels/slabs with any side greater than or equal to 39" (1m), lippage control systems are required") by thin tile manufacturers to help minimize lippage between tile edges—light is consistent across the surface of tile without refracting (as noted in the wall photo).  Natural or artificial lighting no longer highlights imperfections in the tile surface, letting the installer’s craftsmanship come to the fore.  It is important to note, that no matter which type of ‘mechanical lippage tuning system’ you choose, the principle is the same, to ensure 1.) Tile has maximum mortar contact between the back of the tile and the substrate with no voids  2.) Lock down all of the tiles into a single plane, reducing and/or eliminating tile ‘lippage’.