Quote:
Originally Posted by Daywalker  Hi all, grouted a bathroom floor this morning using Granfix Ultimateflex floor grout no problems, tiles spaced using 5 mm spacers, timber floor with 9 mm ply over lay, no under floor heating.
2 hours later found hair line cracks down the centre of every grout line 
Any one else had this happen and whats caused it ????????????. |
How long did you leave the floor tiles to dry before grouting?
Please guys don't use pva for admix use a proper admix for grouts and glues pva is not designed for use with cement based products and you will gain no advantage in doing so.
Using pva in your adhesives and grouts will cause the pva to be slowly attacked by alkali, forming acetic acid as a hydrolysis product. not something you want in a grout or adhesive as they will slowly break down as a result.
Please refrain from using pva as an admix PLEASE!!!!!