Do all Carpet Cleaning Methods offer the same results?
The answer is no! – especially for the residential market.
The carpet cleaning industry has completely transformed itself since the days of the Kirby shampooing vacuüm cleaner in the 70’s. I remember when I as only 5 years old in 1972 and watched the door-to-door Salesman enter our home for a demonstration and proceeded to “Shampoo” an area of our carpet. The next day it was like walking on a dried up paint roller. Looking back, I wonder how many fibers literally broke in half as we walked on the carpet. Mom bought the thing anyways. The vacuüm did last for year but we never used it to clean our carpets again.
These days there are four methods that have created a niche in the carpet cleaning industry. These include 1) industrial shampoo machines made famous by Von Schrader, 2) Host, a method that uses a dry biodegradable absorbent cleaning compound, 3) Bonnet Cleaning - the method of choice by the franchise Chem-Dry that uses club soda (carbonated water) mixed with special cleaning compounds, and 4) Hot Water Extraction, known typically as Steam Cleaning (the only method the carpet manufacturers recommend).
Let’s look at the four methods separately:
The residential market slated “shampooing” as an outdated method and no longer used (The Von Schrader shampoo method is still the preferred method for larger hotels and casino’s). This method uses a slightly wet shampoo mixture applied by a rotary brush with mild suction to extract the dirt. Rinsing is not performed, thus the powerful residue can continue to collect dirt after cleaning, leading to the misconception that carpet cleaning can lead to the carpet getting "dirtier faster" after the cleaning. When wet-shampoo chemistry standards converted from coconut oil soaps to synthetic detergents as a base, the shampoos dried to a powder, and the loosened dirt would attach to the powder components, requiring vacuuming by the consumer the day after cleaning.
Dry compound (Encapsulation)
Dry compound method uses a biodegradable absorbent cleaning compound spread evenly over carpet and brushed or scrubbed in. Surprisingly enough, ground up corn husk was the standard base of this compound for many years. New synthetic polymers emerged in the 1990’s replacing the use of corn husk and improved the encapsulation process. For small areas, a household hand brush can work such a compound into carpet pile; dirt and grime combines with the compound, which is then vacuumed up, leaving carpet immediately clean and dry. Commercial application uses a specially designed cylindrical counter-rotating brushing system. Machine scrubbing is more typical today as the power of these machines is greater than the average household vacuüm cleaner.
Bonnet Method (carbonated water)
Bonnet Method involves mixing carbonated water with cleaning products spayed on the surface of the carpet as a mist, a round buffer or "bonnet" scrubs the mixture with rotating motion. This industry machine resembles a hard-surface floor buffer, but with an absorbent pad, that attracts soil. The pad requires repeated rinsing or replacement as it gets dirty. Technically, with the use of carbonated water, the bonnet method is not a “dry-cleaning” and can involve significant drying time, and usually only addresses the top third of the carpet fibers. Chem-Dry is the nation’s largest franchise using the bonnet method. The carpet manufacturers do not recommend this method.
Hot Water Extraction (Steam Cleaning) – Recommended by the carpet manufacturers
High–pressure hot water extraction (Steam Cleaning) is the process of pre-treating carpet with an alkaline detergent (Acid based detergents for wool and other natural fibers) and then rinsing the pre-treatment along with the dirt and other particulates. A cleaning wand attached to a high-powered vacuüm removes the detergents and dirt. Agitation (several passes with the carpet wand) is usually required to release the dirt and particulates. High-powered truck-mounted hot water extraction machines introduced in the early 90s has revolutionized the cleaning process. Today the technology behind these high-power and high heat machines, coupled with improved chemistry of the detergents, stepped up to produce the safest and most effective cleaning method that the carpet manufacturers took notice and are recommending it as the preferred method to uphold their warranty.