According to a number of Localtraders.com building experts, single-part flexible adhesive is now the industry's preferred type of adhesive.
The main reason is that single-part flexible adhesive allows for a small amount of tile movement, whereas standard set adhesive allows for no movement at all. This is of particular importance when you are laying tiles in an area that is subject to a significant fluctuation in temperature.
A single-part flexible adhesive generally allows between 2.5mm and 5mm of movement, putting it in the S1 classification of adhesives. If an adhesive allows movement of 5mm or more then it is classified as S2. It is important that an adhesive allows the tile to move slightly, as the tile may crack once the adhesive expands and contracts due to temperature fluctuation.
These small margins of movement make this adhesive perfect to use when tiling onto solid structures such as concrete block work. The sources of stress, such as the initial setting movement and drying shrinkage that come with tiling onto solid structures, can be nullified with the use of single-part flexible adhesive.
One of our experts, Colin Beattie from Colin Beattie Floors and Walls, said: “Single-part flexible adhesive is now the number-one choice for a large majority of professionals. The increased flexibility it offers compared to standard set adhesive is extremely important in avoiding tile cracking.”
He continued: “I probably use between 15 and 20 bags each week. It's well priced at around £28 a bag as well, so I feel I'm definitely getting value for money.”
Mr Beattie also explained why it is so important to use differently coloured adhesives, depending on whether you're tiling a floor or wall.
“Grey adhesive is much better to use on floors as they tend to be grey in colour as well, meaning that the adhesive blends in with the colour of the floor. White adhesive is best used on walls and when laying natural stone tiles, as grey adhesive tends to stain them.”
It is important to remember that although single-part flexible adhesive is now the trade favourite, standard set adhesive is not without its uses and is particularly useful when used in a dry area, which is not liable to temperature changes.
Your choice of adhesive depends on the unique characteristics of each job.
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