More than ever, building owners are focused on their bottom line. When cutting cleaning budgets or reducing interim services, routine carpet extraction is often the first to go. However, by understanding and utilizing low-moisture carpet cleaning techniques, building service contractors can keep carpet care a part of the program.

Low-moisture carpet cleaning technology provides a number of advantages. Facility managers appreciate the faster dry time than conventional methods. In addition, these systems are green because they are water- and energy-efficient, and there is less contaminated wastewater as a result. For BSCs, these systems are easy to learn and there is less risk of over-wetting, re-soiling and wicking.

Dry compounds

Dry compounds are used for interim and restorative cleaning. This no-moisture system uses absorbent compounds containing detergents or solvents that are disbursed and agitated into carpets. After up to 30 minutes of dwell time, the detergents or solvents dissolve oil films on carpet fibers, which free the soil from the carpet fibers. Once this has occurred, a simple vacuuming or pile lift procedure removes the compound along with the soil. It’s the driest way to clean carpets, excluding vacuuming, because no moisture is used at all. Often this method is used in schools or public facilities when drying time is at a premium. There is no danger of over-wetting the carpet, and the process eliminates all wastewater.


Foam is a minimum-moisture system used for restorative cleaning. It is very unlikely that over-wetting will occur. After vacuuming, dense foam is produced through mechanical aeration and distributed via a mechanical brush. The foam is generated inside extraction equipment by mixing cleaning solution with pressurized air. It is brushed into the carpet fibers and then vacuumed out. A wet vacuum is typically incorporated into most foam cleaning equipment, which extracts the excess foam and suspended soil. It’s important to remove all foam residue, otherwise it can interfere with later attempts to clean the carpet. For example, chemicals used at a later date may actually trap new soil in the fibers.

Hydrogen peroxide-based products

Hydrogen peroxide-based cleaners use oxygen to destroy stain molecules. Most of these products can be sprayed on and left to dry. The product dries to a powder and is vacuumed away along with the stain. This method will also reduce the likelihood of re-soiling, and there is no residue left behind.


In this treatment, a low-moisture, low-residue cleaning product is applied using a sprayer and is agitated using a counter-rotational brush machine after normal vacuuming. In fact, the newest machines combine both of these steps to further increase efficiency and save time. The machine agitation lifts the pile, which helps free soil from the carpet fibers. Since the encapsulation machines do not require the time or cost of running long hoses or being mounted to trucks, cleaning can be performed at a lower cost. It also cleans the fiber on all sides, promoting a higher level of cleanliness. After the carpet is dry, vacuuming is recommended. This process produces no wastewater because the encapsulated soil is vacuumed from the carpet as dry soil. A contractor can expect cleaning rates of 2,000 to 3,000 square feet per hour with no rinsing needed.

Low-moisture extractors

The development of low-moisture carpet cleaning equipment is another important innovation. Most carpet experts agree that even if other extraction methods are used, eventually, the carpet will need to be restored using traditional hot water extraction. Even with all the innovations previously noted, hot water extraction is often the most effective and safest restoration method. However, hot water extraction methods use 319 percent more energy to clean the same square footage as dry carpet cleaning technology. This translates into 77 percent higher emissions. Using a low-moisture method can reduce electricity usage by 85 percent.
Earlier versions of carpet extractors used too much water to clean carpets, often as much as two or three gallons per minute. In response, manufacturers have started to introduce low-moisture extractors, which use as little as 0.8 gallons of water per minute. The better units will have counter-rotating brushes to agitate the carpet and further loosen the soil trapped within.

BJ Mandelstam is the founder and president of Cleaning Matters, a Denver-based custodial consulting practice. She was also the owner of an award-winning contract cleaning company for many years. For more information, visit

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