Hire Machine or Professional Clean?

There is a fair question behind every hire machine in a supermarket foyer: if the machine uses the same method as the professionals, why pay someone else to do it? It deserves a straight answer rather than a sales pitch, so here is what is genuinely different, and where it matters most.

This applies equally to machines bought for the home and to the ones hired by the day from supermarkets and DIY stores. They are the same class of equipment.

They work the same way, at a different scale

Hire and home machines use the same extraction principle as professional equipment. Water and cleaning solution go into the carpet, and the machine draws them back out along with the soil. The principle is sound. The difference is in how well each part of that exchange is done.

In our experience a hire machine runs at a lower temperature and with weaker suction than professional equipment, and leaves more water in the carpet. That is our view from the corrective work we are called out for, not a laboratory comparison. The Carpet and Rug Institute describes hot water extraction as the most common professional system, and says do-it-yourself machines are effective at cleaning spots and spills and give an interim clean, but should not replace periodic deep cleaning by a professional.

The water that does not come back out

Some of the water stays in the carpet. The Carpet and Rug Institute advises making dry passes after the wet pass to extract as much water as possible. Water that stays brings three specific risks:

• Shrinkage and rippling. The IICRC says woven area rugs may shrink or buckle after cleaning, and that the moisture from cleaning often swells a carpet’s backing and causes some rippling.
• Delamination. A tufted carpet is built in layers, and delamination is the separation of its primary and secondary backings. The IICRC lists prolonged or repeated exposure to water among the causes, and says it is rarely caused by proper cleaning.
• Mould growth. Damp that lingers in the pile and underlay is an invitation.

None of these are certainties. They are risks that rise the wetter the carpet gets and the longer it stays wet. Low-moisture cleaning keeps the amount of water down, and the IICRC says low-moisture methods lessen the risk of shrinkage without removing it. Our guide on low-moisture versus hot-water extraction covers the difference.

Why the carpet looks clean, then does not

There is a second problem that has nothing to do with water: residue. The Carpet and Rug Institute says that using more cleaning solution than the recommended dilution can leave excess residue in the carpet, which contributes to rapid resoiling. The product matters as well as the dose: WoolSafe lists home-machine solutions it has approved as safe and effective on wool.

It is worth knowing what an optical brightener does, because some cleaning products contain one. An optical brightener is a masking agent: it makes the carpet look brighter without cleaning it, so the dirt stays in the pile. That dirt shows more and more as time goes on, and the carpet needs cleaning again sooner.

We do not use optical brighteners, because they hide dirt rather than remove it. The solutions we use are neutral, and every method we use, our dry system included, extracts them fully, so nothing is left in the fibres to draw dirt back.

The result can be a familiar pattern. The carpet looks good the day it is cleaned, then re-soils quickly. Residue is one cause among several: the IICRC also lists soil tracked in from outside, body oils from people and pets, and a carpet used again before it was thoroughly dry.

Where it matters most: wool and natural fibres

If your carpet is wool, or a natural fibre such as sisal or seagrass, the calculation changes. WoolSafe describes sisal, sea grass and coir as sensitive to moisture, and says the damage done to carpets in wet cleaning usually comes from over-wetting, too much mechanical action and unsuitable chemicals.

Some damage cannot be undone. The Woolmark Company describes the felting wool undergoes with heat, moisture and agitation as irreversible, and Alternative Flooring says a spill can leave a permanent water mark or ring on sisal.

If you are not certain what your carpet is made of, that is worth establishing before anything wet touches it. Our guides on cleaning wool carpets and natural-fibre carpets and rugs cover how to tell and what each fibre needs.

What we actually get called out for

We would rather be straightforward about our own interest here, so: a good deal of our corrective work is putting right the over-wetting and residue that hired machines leave behind. That is not an argument that you must never use one. It is the honest answer to what we see, and it is why the wool and natural-fibre warning above is the part we would most want you to take seriously.

The work worth doing yourself

Plenty of carpet care genuinely belongs at home. Prompt, correct treatment of a spill matters: the Carpet and Rug Institute says the key is to act quickly, and it also advises a professional deep clean every 12 to 18 months. Our guide to carpet care at home covers how to blot a spill properly, and which stains are permanent sets out honestly what will and will not come out.

If you would like a view on your own carpet before deciding either way, our assistant will identify the fibre from a description or a photo and tell you plainly what it needs, including when the answer is that it does not need us yet.