Tile Doctor Grout Colourant Used to Restore Grout in an Oxford Street Store WC London W1
Recently we were tasked by a well-known department store on Oxford Street to renovate the Porcelain Tile and Grout in the staff bathroom. The tiles were heavily soiled, and the grout lines were deeply ingrained with dirt and discolouration, making the space look untidy and unhygienic despite the reasonable condition of the tiles.
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Porcelain tiles are impervious and so very easy to clean and maintain, grout however is a different matter as the rough cementous surface easily traps dirt. This is exacerbated by the smooth porcelain tile as dirt becomes washed off the tile straight into the grout line where it becomes trapped turning it black over time.
We do have a solution for this problem though; it involves deep cleaning the grout and then colour sealing it with a Tile Doctor Grout Colourant which are available in 11 different colours and shades. The colourant also adds a protective barrier to the grout preventing discoloration.
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Deep Cleaning Porcelain Floor Tiles
To start, a strong dilution of Tile Doctor Pro-Clean was sprayed onto the tile. This is a professional-grade alkaline cleaner specifically designed to lift embedded dirt, grease, and grime from tile and grout. Then after ten minutes it was scrubbed with a rotary machine fitted with a carbon brush. This worked the cleaner into the tiles and grout to break down years of built-up soil and tackled the toughest dirt removing a significant amount of grime in the process.
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There was still more to do however so to ensure a thorough clean and prepare the tiles for the next stage, the tiles were cleared again using more Pro-Clean and with a black scrubbing pad. This combination of Pro Clean and mechanical agitation safely lifted all remaining grime from the glazed porcelain without damaging the tile surface, leaving it fully prepared for the grout treatment which came next.
Grout Cleaning and Restoration
The grout did respond to the tile cleaning however it was too ingrained and stained to restore with cleaning alone. The customer did not want the inconvenience of regrouting which is messy and takes a long time so I recommended the colour seal option mentioned earlier. We find recolouring as the best option when it comes to improving grout and providing long-term protection.
Because the grout was heavily soiled, it needed 2 and some places 3 coats of white colourant to achieve a consistent and even finish across all lines. This professional-grade product recolours and seals the grout simultaneously, giving it a refreshed, uniform finish and protecting it against future staining, wear, and discoloration.
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The result was a revitalised back-of-house bathroom, with the porcelain tiles looking cleaner and grout lines bright, consistent, and protected. With this being a staff toilet, we were able to work during the day which isn’t always possible when working in public areas. The customer was extremely happy with the outcome, a professional, long-lasting clean that made the space look far more presentable.
For future maintenance cleaning I recommended the use of Tile Doctor Neutral Tile Cleaner, it’s a mild yet effective cleaning product that doesn’t contain anything that might impact the grout colourant.
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Source: Grout Cleaning and Restoration Products and Services in Oxford Street London W1









