Clean dirty grout — HomeGraft

Clean discoloured or mouldy tile grout safely, step by step, in one session with basic tools.

GR-01Clear and ventilate the areaMove bath mats, bottles and rugs out of the way so you can reach every grout line. Open a window or door, especially in a bathroom, because grout cleaners and bleach give off strong fumes in a small space.

GR-02Put on gloves and eye protectionGrout cleaners and bleach irritate skin and eyes. Wear rubber gloves and, if you're using anything bleach-based, safety glasses too.

1 pair · Rubber gloves

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1 each · Safety glasses

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GR-03Dry-brush loose dirt firstBefore adding any liquid, run a stiff nylon brush along the grout lines to lift loose grime and dust. This stops you working mud into the grout once it's wet.

1 each · Stiff nylon brush

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GR-04Test your cleaner on a hidden patchDab a small amount of whatever cleaner you're using onto an inconspicuous bit of grout, such as behind a bath panel or in a corner. Wait 5 minutes and check the grout colour hasn't lifted or the tile finish hasn't dulled before treating the whole area.

GR-05Apply the grout cleanerFor everyday grime, use a shop-bought grout cleaner or a paste of bicarbonate of soda and water. Spread it along the grout lines with an old toothbrush or grout brush and leave it to work for 5 to 10 minutes; check the product label for exact timing.

1 bottle · Grout cleaner spray

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1 box · Bicarbonate of soda

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1 each · Old toothbrush or grout brush

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GR-06Treat black mould separately with bleach if neededFor black or pink mould spots, use a bleach-based mould spray or a weak bleach solution on white grout only, since bleach can strip colour from tinted grout. Never mix bleach with any other cleaning product, including bicarbonate of soda mixes or limescale removers, as this can produce dangerous fumes. Leave it to dwell for the time stated on the bottle, usually 10 to 15 minutes.

1 bottle · Mould and mildew spray

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GR-07Scrub the grout linesWork the brush along each grout line with short strokes, following the direction of the line rather than scrubbing across it. Rinse the brush often so you're not spreading dirt back onto clean areas.

GR-08Rinse thoroughlyWipe down the whole area with a clean, damp cloth or sponge to remove all traces of cleaner. Leftover cleaner residue can attract dirt again quickly, so rinse more than once if the surface feels tacky.

2 each · Microfibre cloths

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GR-09Dry off and check the resultDry the tiles and grout with a clean towel or cloth. Check the lines in good light and repeat GR-05 to GR-08 on any stubborn patches.

GR-10Seal the grout once fully dryThis step is optional but helps stop staining coming back. Once the grout is completely dry, usually after 12 to 24 hours, brush on a grout sealer along all the lines and let it cure as per the tin.

1 bottle · Grout sealer

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1 each · Small foam brush

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GR-11Tidy upRinse brushes and cloths well, especially if bleach was used, and let them dry away from other laundry. Put mats and bottles back once the floor or shower area is fully dry to avoid slipping.

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