There is no unified standard for the size of tile joints. In addition to meeting the thermal expansion and contraction factors of the tiles themselves, the size should also be determined based on the decorative effect of the tile laying. Generally, the following suggestions can be used as a reference:

Wall tiles joint suggestion:

For kitchen and bathroom wall tiles, the joint size should generally be around 1-1.5mm, not less than 1mm, and an air nail or packaging bag can be used as a reference. The effect can also be achieved by widening the joint to 5mm, which is more suitable for some antique tiles, exterior wall tiles, and balcony tiles.

Floor tiles joint suggestion:

For tiles such as vitrified tiles, the joint size is generally around 1.5-2mm. The joints of floor tiles are generally not too large, as excessive gaps can easily accumulate dirt and affect cleaning.

Generally speaking, different widths of tile joints are suitable for the following types of tiles:

• 1.0mm or 1.5mm joints are suitable for small square, rectangular, or hexagonal tiles.
• 2.0mm to 2.5mm joints are suitable for medium-sized square or rectangular tiles.
• 3.0mm to 4.0mm joints are suitable for large square or rectangular tiles.
• Joints above 5.0mm are suitable for particularly large tiles and natural stone.

It should be noted that in some cases, you may need to consider tiles of different sizes at the same time, such as when creating mosaic patterns on complex surfaces. In this case, you may need to use joints of different widths to deal with tiles of different sizes to ensure the consistency of the overall effect.