I inspected the tiles and confirmed this was the worst case of grout haze I had ever seen; unafraid, I proceeded to carry out a test clean (you can see this reflected in the video above) and this demonstrated successfully that the tiles could be restored.
Cleaning Patio Quarry Tiles
Contented with the results of the test clean I proceeded to clean the rest of the floor. For this I used Tile doctor Grout Clean-Up which contains concentrated acid and is designed to penetrate below the surface to remove grout smears; this was diluted 1 to 1 with water which is a very strong mix. I sprayed the solution onto the tiles, working 1sqm at a time, leaving it to dwell on the tiles for a few minutes before scrubbing the tiles by hand with a rough pan cleaner. I then rinsed the area off with water and used my wet vac to remove the soiled solution. The strong mix had the desired effect on the Quarry tiles but it was necessary to go over the area again after spotting some of the worse stains the first application had missed. Happy with the result, I carried out this process across the rest of the patio, working 1 sqm at a time.
Sealing Kitchen Quarry Tiles
When I was done the customer was very happy with the result, and now had a patio they could use. The customer was keen to carry on with their DIY project, and wanted to seal the patio themselves, so I advised them to use Tile Doctor Color Grow, which is a color intensifier and impregnated sealer; this will both protect and enhance the reclaimed quarry tile into the future.