This type of floor can be restored by just following a few rules..These tiles floors should not be soaked with large volumes of water as this could eventually loosen the tiles, i would use Aqua mix sealer & coating remover on this floor to remove any glue, paint etc. The once i have used this i would use Aqua mix heavy duty tile & grout cleaner and some Nano scrub, use a low speed scrubbing machine, clean relatively small areas and when each has been well scrubbed rinse several times with clean water, once the whole floor has been done, do it all over again, throughout this process it is important to monitor the cleaning solution and rinsing water, change them frequently as they get dirty. Acid cleaning solutions can be used especially where there is grout, or cement and levelling compounds have left a residue on the tiles. Only use acid where you will not damage fabrics or skirting, and always test on a tile before commencing. Once the tiles are clean it must be sealed Acrylic sealers are probably the best for this type of floor, these are easy to apply and the amount of sheen can be tailored to what the customer wants. Avoid using natural waxes for these floors as these trap dirt and discolour as the coats accumulate, and can be slippery and require alot of maintenance. You will not learn how to clean these on a Prochem course as i have done there course.
