Grout stain removal from slate tiles
One of the most frequent questions we are asked is how can I get stubborn grout off my slate tiles. This is usually caused when grout is left to sit for too long without wiping it off or grouting to big an area of the slate tiles before cleaning the grout from the surface.
Depending on the severity of the grout on the surface there is no quick or easy fix. When slate floor tiles are grouted & a layer of sealant has been applied then the tiny pin prick holes on the surface are blocked which enables easy removal of the grout but if you have left a large amount of grout on the surface then it could be very difficult to remove.
One option would be to buy a mild grout stain remover & see if this shifts any of the grout, if it does not then you will need something much stronger which I suggest you call us & we can point you in the right direction for this.
Many times in the past we have had customers call us to ask for help on this matter to be told that there builder tried to cut corners with not applying a coat of sealer before grouting & were left with varying degrees of grout residue on the surface. The builder then suggested brick acid to try to remove the grout but this can completely ruin the floor, THIS WE DO NOT RECOMMEND.
There are products on the market to rectify these problems but they require a lot of work & scrubbing so we always recommended to seal your slate floor before grouting.