Carpet shampoo, steam or dry cleaning: which one?

Which carpet cleaning method is best?

No single method wins everywhere. The choice depends on the fibre, how soiled the carpet is, and how soon the room has to be back in use.

For a fitted carpet in a home that has not been deep cleaned for a year, hot water extraction gives the most thorough result, because it is the only common method that rinses soil out of the pile and carries it away. For an office corridor that cannot be closed, or a carpet that must not get wet, a low moisture method is the practical answer. Shampoo has its place on flat, greasy carpet, provided an extraction rinse follows.

Professional cleaners often combine them: a shampoo or a brushed in solution to loosen soil, then extraction to remove it.

Is steam cleaning really done with steam?

In the carpet trade, no. What is sold as steam cleaning is hot water extraction. A machine sprays heated water and detergent into the pile under pressure, and a vacuum slot directly behind the jets pulls it back out along with the soil it has loosened. The vapour rising from the wand gave the method its name.

Done properly, the sequence is a dry vacuum, a solution sprayed on and left to work for some minutes, agitation with a brush or a pile rake, extraction, and then extra passes with the vacuum alone. Those dry passes decide how wet the carpet is left. A carpet that squelches afterwards, or is still damp the next day, has been cleaned badly.

When is dry or low moisture cleaning the better choice?

• Encapsulation uses a small amount of liquid that is brushed into the pile and dries into brittle crystals around the soil. Routine vacuuming then removes them. The carpet can be used within about an hour.
• Dry compound cleaning spreads slightly damp absorbent granules over the carpet. A machine with two rotating brushes works them through the pile, and they are vacuumed out with the dirt attached.
• Bonnet cleaning spins a damp pad over the surface. It improves the look quickly but touches only the tips of the fibres.

These methods suit offices, hotels, shops and any carpet on a raised floor with cables beneath. They also suit fibres that react badly to water, such as sisal, jute and some viscose blends. Their limit is depth: they maintain a carpet between deep cleans and do not flush out what has sunk to the backing.

Why does a carpet look dirty again soon after shampooing?

There are two causes. The first is residue. Shampoo is designed to foam, and foam left in the pile dries into a sticky film that grabs dust from every shoe. The carpet looks clean for a fortnight and then greys faster than before. Rinsing by extraction prevents it.

The second is wicking. When the backing or underlay is soaked, moisture travels up the fibres as the carpet dries and brings dissolved soil with it. Old spills that seemed to have gone come back as brown rings a day later. Using less water, extracting thoroughly and drying fast are the cure.

What difference do Dubai conditions make?

Sand comes first. The fine grains carried in on shoes sink to the base of the pile, and no wet method removes them well. They have to be vacuumed out dry, slowly and from two directions, before any water goes down. Skip that step and the cleaning solution turns the sand into mud.

Humidity is the other factor. A damp carpet in a closed room in August dries slowly and can smell sour within a day. The AC should stay on, air movers should run across the floor, and furniture legs should sit on plastic tabs or foil until the pile is dry, otherwise wood stain and rust transfer into the carpet.

What can I do myself, and when should I call a professional?

• Vacuum twice a week in rooms that are used daily, and keep a mat inside and outside each entrance.
• Blot spills with a white cloth and cool water, working from the outside in.
• Avoid powders and foams that stay in the pile, since they add to the residue.
• Keep shoes off bedroom carpets.

Call a professional for a full deep clean once or twice a year, for pet urine, for a carpet that has been flooded, and for wool or anything marked dry clean only. The MELLS surveys the carpet on a site visit, names the method in a written quotation, and a supervisor checks the finished rooms.