Most ARDEX adhesives are C2 classification. C1 = Normal adhesive: initial adhesion strength of greater than 0.5N/mm2. C2 = Improved adhesive: higher initial adhesion strength of greater than 1N/mm2.
An example of the adhesion strength is, if a C2 adhesive is used to fix a 100mm x 100mm tile to a suitably strong concrete ceiling, the adhesion strength can support a 1 tonne weight. There are other considerations you need to think about when selecting your adhesive – just because it’s got a “high number”, doesn’t mean it will be the right adhesive for you.
Think about how the adhesive is to apply – is it easy to apply? Is it smooth to trowel out? Do you need a pourable adhesive?
Maybe you need to build out the adhesive in places such as window reveals, or small spots on the floor.
Does your adhesive need to set quickly for a fast-track application, or are there temperature / humidity considerations where you might need a slower setting adhesive.
There are so many things to consider – not just what the classification of the adhesive is. Remember these are just a guide to the performance of the adhesive and not whether your adhesive is suitable for your individual project.