Natural stone tiles have adorned floors and walls for centuries and cleaning your tiles before grouting will help keep them in showroom condition for almost as long. The same to goes for modern porcelain tiles, be they polished, matt or a textured surface.
Before fixing, and preferably at the quoting stage, the gap between the tiles should be agreed with your tiler. Referred to by tilers as 'grout lines', the gap size you opt for depends on the type of tile you're using for your project, the type of substrate the tiles are being fixed to and personal preference, but you should also consider the type of grout to be used. Common practice is 2-3mm for wall tiles and 3-5mm for floor tiles.
The key difference in tile type, in relation to grout lines, is whether your tile is rectified or not. A rectified tile is one which is cut or manufactured to a precise, measured size. Rectified tiles can be either porcelain such as StoneStore’s Calacatta Minimale, or natural stone such as our classic Italian Bianco Carrara marble tiles.
After firing, porcelain tiles undergo a secondary process where tiles are mechanically cut or ground on all sides to precise and consistent dimensions, ensuring uniformity across each batch of tiles. This unique feature of rectified tiles allows an installation to be fixed with narrow grout lines of 2-3mm, creating a seamless, stylish look.
The use of grout lines disguises size differences between non-rectified tiles, ensuring a balanced installation is achieved. If such tiles are laid butting up to each other with no grout line in between, the slight size variation between the tiles would accumulate and cause alignment issues, leaving your room looking wrong. Grout lines for non-rectified tiles tends to be 3-5mm to allow for the variations in tile size.
The floor substrate should be taken into consideration when determining grout line size. No matter how well tiles are installed, tiles fixed to wooden substrates are prone to minute but consistent movements. In this case grout lines are essential as without them the tiles will rub against each other causing chipping, cracking, or de-bonding from the adhesive or substrate.
The size of the grout line and tile type can determine the type of grout to be used. Some grouts are only suitable for up to 3mm gaps, whereas a wide-joint grout may not be suitable for a highly polished tile. If you have a wooden floor substrate, a flexible grout should be used to absorb any movement. Discuss grout options with your tiler prior to installation, or call us for advice on 0161 277 6850.
Once fixed, but before grouting, newly laid tiles should be cleaned with LTP Grimex to remove surface residues and impurities. Often this stage of preparation is overlooked as tilers will simply wipe the surface with water - this is inadequate, as small dust and dirt particles not visible to the naked eye will be embedded in the micro-pores of the tile during the installation process. These particles will be locked in when the grout is applied and, as a result, the surface will be appear smeared and will be difficult to buff to the required finish.