What is seamless joint tiling?

With industry best specifications and standards over 10 times stricter than international requirements for porcelain tiles, Kaolin are able to offer a product so exact that grout joints as small as 0.5mm can be used.

Grout joints have always been the biggest downfall of tiles, often leading to disappointment in the finished job and years of frustration for the end-user.

With our “Seamless Joint” tile range we can now specify grout joints so fine that they become virtually invisible in the finished installation.

How do we achieve this? It comes down to 4 critical areas where Kaolin tiles excel over the competition.


1. True to size

All Kaolin tiles are true to their mentioned size. A 900x1800mm is exactly that. Most tile manufacturers cut tiles from larger formats and are always slightly off-size. 900x1800mm tile would be in reality 895x1798mm for example.  At Kaolin we are very proud of the fact all our tiles are “True to Size”.

There is nothing more frustrating than ordering a tile that is advertised as 600x1200mm or 750x1500mm and then finding out it is 5mm smaller (595x1195mm or 745x1495mm). This becomes even more so when utilising more than one tile in the same area and trying to get the grout lines to line up.


2. Surface Flatness 

Kaolin pride ourselves on producing some of the flattest tiles available. Our 900x1800mm Seamless Joint Tile range have a factory allowance of only + or – 0.02% height deviation over the surface of the tile, this is almost 20 times stricter than the international standards of 0.4% allowed. While international standards cap this deviation at a maximum + or – 1.8mm, Kaolin standards only allow a maximum -.3mm to +.4mm surface variation over 1.8m.

This allows us to position the tiles closer without fear of lipping. In fact, we will also support bricklaying of Seamless Joint tiles with as little as a 1.5mm grout joint.

3. Length and Width

A small gout joint cannot work unless your tiles are consistently the same size and straight.

International standards allow for a maximum + or – 1mm size deviation from tile to tile, this can lead to 2 tiles being up to 2mm different in size, this is why tilers have larger grout joints to allow for this variation.

This is unacceptable to us at Kaolin, so we have set our Seamless Joint tiles to have no more than 0.3mm variation between any two tiles. With a stack bond lay we now support joints down to as little as 0.5mm using our levelling clip system and approved installation methods.


4. Water Absorption 

Tiles absorb water and as they do, they expand. This expansion can lead to tiles becoming “drummy” as they shear the bond to the adhesive and even pop up as expansion limits are reached and appropriate expansion joints are not included.

All Kaolin Seamless Joint tiles have an average water absorption rate of only 0.04% which is more than 10 times stricter than the international standard 0.5% and only a fraction of what natural stone can absorb,  which virtually eliminates moisture expansion issues in tiles.

5. True recitfied Edge

Kaolin tile edges are a true 90 degrees. Most manufacturers put a slight bevel on the edges of their tiles as they are often cut down from bigger sizes. This cutting leads to small chips along the edge of the tile and no other option than to put a bevel on the tile to remove the chipping.

As Kaolin press all their tiles to the required size we never cut the tiles down and never have to bevel the edge.

For the end user this means that the size spacers used will be the finished grout width.

Use a 0.5mm spacer with a kaolin seamless joint tile and the grout will be only 0.5mm

When the tile has a bevel or chamfer it can widen the grout joint considerable. This is often why 1.5mm spacers end up leaving a 3mm grout joint.