You mop every week. The tiles look fine. The grout, somehow, keeps getting darker. You're not imagining it, and it's not because you're mopping wrong — it's because mopping can't clean grout, and in fact makes it worse.
Why grout goes grey
Grout is porous — it's basically cement, sand and tiny air pockets. Tiles are sealed and smooth, so when you mop, the dirty water runs off the tile and settles in the lowest point, which is the grout line. The water evaporates and leaves the dirt behind, a little more each week. Over a few years the grout in the kitchen and hallway ends up two shades darker than the grout under the fridge, which nobody's ever mopped.
What doesn't work
- Mopping harder, or with more product. More dirty water into the grout.
- Bleach. It lightens the surface temporarily, damages the grout over time, and does nothing to the soil below the surface.
- Scrubbing by hand with a toothbrush. It works, if you have a weekend and knees to spare, and it still doesn't rinse the loosened soil away.
- Steam mops. Not enough pressure to lift embedded soil, and no way to recover the water.
What a professional tile and grout clean actually does
- Alkaline pre-spray to break down grease, body oils and detergent residue in the grout. This dwells for ten to fifteen minutes.
- Agitation with grout brushes on the lines and a rotary brush on the field.
- High-pressure hot water rinse with a turbo tool — the spinning head you see in the photo — connected to the truckmount. It blasts water into the grout and recovers it instantly, so nothing splashes onto your cabinets and nothing dries back in.
- Hand detailing of edges, corners and around fixtures where the tool can't reach.
The before-and-after is dramatic because the grout isn't stained, it's just full of dirt. Once it's flushed out it comes back to close to its original colour.
Should you seal the grout afterwards?
Sealing fills the pores so dirt sits on top instead of soaking in, which makes mopping actually work for a change. We recommend it for kitchens, entries and any grout that's been cleaned back to a light colour. Most sealers last two to three years. If grout is permanently stained or crumbling, a colour seal that coats the grout in a fresh, uniform colour is the better option — ask us and we'll tell you honestly which you need.
What it costs
Tile and grout cleaning is from $6 per square metre for most homes and from $4 for larger areas, with a $260 minimum visit. A typical kitchen and living area of 40 square metres is around $380; a whole-house tiled floor of 120 square metres is around $740. It bundles well with carpet or couch cleaning, since the truck is already there.
By A1 Carpet Cleaning