BAL FastFlex is the one to use when your substrate might bend or expand; this is a cement-based adhesive with added polymers, which give it super-flexibility. This makes it useful for projects where your substrate may shrink or deform over time and where you are worried about a conventional adhesive cracking or coming loose. BAL’s technical data says that this adhesive can deform by ±5mm. BAL FastFlex is suitable for indoor and outdoor use.  Mix carefully with water to make a smooth paste. Offers an open time of 20 minutes (ie the time, after application, when the adhesive will make a good bond with tiles placed on it).  FastFlex does set quickly - this is one of its virtues, but it does mean that it lasts less long in your pot and you may need to make up a new mix more often than with other adhesives. Can be used with ceramic, porcelain, vitreous glass and some natural stone tiles. Ready for grouting in 5 hours. Coverage approximately .5m². Supplied in an oblong resealable plastic ice cream-style tub. Weight 800g.

You must wear gloves when mixing and using adhesive or grout; they contain cement which is a skin irritant. When you clear up, don’t let dirty water from the cleaning of tools and containers go down your drains. The cement, even in what seems like quite small amounts, can block drains.  Instead, pour wastewater into a container (an old bucket or food container) and let it stand for a day or so.  It will separate and you can then pour the clear water down the drain and scoop any cement gunk into a plastic bag which you can tie up and put in your bin.