Posted: Tue Aug 23, 2016 4:21 pm
A local contractor laid a patio (approx. 200msq2) and used Geofix "Paving jointing compound" to grout. The slabs are light grey flamed granite supplied by Rock Unique.
The slabs were laid on a concrete base, I think it is fairly thick and some kiln dried sand was brushed into the joints before the use of Geofix for the joints. The joints are mostly less than 5mm. The grouting took place at the end of June and immediately it was clear that the finish was very poor with black stains appearing along the lines of the joints.
The contractor has returned on a number of occasions to try to remedy the staining using a jet was and more latterly a cleaner (which he assured me was safe for the granite). Despite these efforts the staining has not disappeared and there is now residue on the slabs from various cleaning products.
I have discussed the problem with Geofix as well as the supplier of the slabs who are both of the view that the staining should disappear over time. Geofix were reluctant to specify how long this might take; the suppliers of the slabs suggested it may take many months.
As well as staining the grout has disintegrated in many places so he patio looks terrible. Photos of the patio are on DropBox
https://www.dropbox.com/sh....Sa?dl=0
The contractor has suggested that the entire patio is sandblasted and then re-grouted. Whilst this might remove the staining I am concerned that sandblasting would change the finish of the surface from flamed to something quite different, and may well change the colour of the slabs. This "solution" seems to be motivated by a desire to release payment rather than to produce the desired finish.
So...questions:
1. does anyone have any experience of sandblasting flamed granite? Should I resist this suggestion?
2. Are there any other solutions (short of ripping up the patio and replacing all the slabs) other than waiting for the stains to fade away?
3. If the matter becomes litigious are there independent experts on paving that can provide a view?
Any other comments warmly receivd
Thanks
David
The slabs were laid on a concrete base, I think it is fairly thick and some kiln dried sand was brushed into the joints before the use of Geofix for the joints. The joints are mostly less than 5mm. The grouting took place at the end of June and immediately it was clear that the finish was very poor with black stains appearing along the lines of the joints.
The contractor has returned on a number of occasions to try to remedy the staining using a jet was and more latterly a cleaner (which he assured me was safe for the granite). Despite these efforts the staining has not disappeared and there is now residue on the slabs from various cleaning products.
I have discussed the problem with Geofix as well as the supplier of the slabs who are both of the view that the staining should disappear over time. Geofix were reluctant to specify how long this might take; the suppliers of the slabs suggested it may take many months.
As well as staining the grout has disintegrated in many places so he patio looks terrible. Photos of the patio are on DropBox
https://www.dropbox.com/sh....Sa?dl=0
The contractor has suggested that the entire patio is sandblasted and then re-grouted. Whilst this might remove the staining I am concerned that sandblasting would change the finish of the surface from flamed to something quite different, and may well change the colour of the slabs. This "solution" seems to be motivated by a desire to release payment rather than to produce the desired finish.
So...questions:
1. does anyone have any experience of sandblasting flamed granite? Should I resist this suggestion?
2. Are there any other solutions (short of ripping up the patio and replacing all the slabs) other than waiting for the stains to fade away?
3. If the matter becomes litigious are there independent experts on paving that can provide a view?
Any other comments warmly receivd
Thanks
David
