Yes, professional carpet cleaning can damage a carpet if the wrong cleaning method is used. But that doesn’t mean professional carpet cleaning itself is damaging. In fact, when the proper cleaning method, equipment, temperature, pressure, cleaning agents and amount of moisture are used, professional cleaning can help extend the life of your carpet.
After more than 55 years in the carpet and upholstery cleaning business, one of the most important things I have learned is that there is no single method of professional carpet cleaning that is right for every carpet.
There are different types of professional cleaning, and there are many different types and constructions of carpet. The cleaning method needs to be matched to the carpet.
Carpet and Area Rugs Are Not the Same
Before discussing cleaning methods, it is important to make a distinction between wall-to-wall carpet and area rugs.
There are many different types of wall-to-wall carpet, but two of the basic constructions are cut pile and loop pile.
Area rugs can be even more complicated. They can have different fibers, dyes, foundations, borders and construction methods, and many require specialized procedures that would never be appropriate for wall-to-wall carpet.
Let’s start with carpet.
Cut-Pile and Loop-Pile Carpet
With a cut-pile carpet, the yarn has been cut at the top of the carpet. Many cut-pile carpets also have a twisted yarn construction.
This type of carpet can be particularly sensitive to aggressive agitation.
When a rotary machine or other mechanical equipment is used too aggressively, it can distort the fibers. With a twisted cut-pile carpet, the agitation can actually affect the twist of the yarn and change the appearance of the carpet.
The carpet may be perfectly clean, but the pile can look different afterward.
Loop-pile carpet is different. Because the yarn remains in a continuous loop, these carpets can generally tolerate considerably more vigorous mechanical agitation without producing the same type of visual distortion.
This is one of the reasons I don’t believe in simply choosing a cleaning method because it is popular or because it worked well on another carpet.
The construction of the carpet has to be considered first.
Rotary Agitation and Bonnet Cleaning
One of the most common forms of mechanical agitation comes from rotary equipment.
Rotary cleaning certainly has its place. In fact, many years ago the bonnet cleaning system was developed primarily as a commercial carpet-maintenance method.
A bonnet system uses a rotary machine, commonly operating at approximately 175 RPM, to rotate an absorbent pad over the carpet surface.
Cleaning solution is applied to the carpet, and the rotating pad helps loosen and absorb soil from the upper portion of the carpet.
Many bonnet pads contain cotton or other absorbent materials. Some also contain nylon or other synthetic fibers that help generate friction and heat as the pad rotates over the carpet.
One of the advantages of this system is that relatively little moisture is introduced into the carpet, allowing it to dry quickly.
But there is an important distinction.
Bonnet cleaning was designed primarily as a maintenance system between more thorough extraction cleanings.
It can be very useful on appropriate commercial looped carpet.
I would not recommend using aggressive rotary agitation on a susceptible cut-pile carpet, particularly one with a twisted yarn construction.
The same mechanical action that can be perfectly appropriate for a commercial loop carpet can distort a residential cut-pile carpet.
Dry Compound Cleaning
There are also dry-cleaning systems that use an absorbent compound.
The compound is distributed over the surface of the carpet—somewhat like using a drop spreader to distribute fertilizer over a lawn.
The compound is then mechanically agitated into the carpet so that it mixes with and absorbs soil from the carpet fibers.
After the compound has had sufficient time to work, it is removed by vacuuming.
This system can work well on certain types of commercial looped carpet.
However, there is another factor that is often overlooked: dwell time.
The compound needs sufficient time to work.
Some systems recommend allowing the compound to remain in the carpet for several hours or longer. In a commercial environment, however, it may not be practical to keep a carpet out of service for that amount of time.
As a result, the recommended dwell time isn’t always possible.
Again, I would consider this type of cleaning primarily for appropriate commercial looped carpet rather than assuming it is the best method for every residential carpet.
Hot-Water Extraction
The most common deep-cleaning method used today is commonly called steam cleaning, although technically the process is hot-water extraction.
It can be performed using either a truck-mounted machine or a portable extraction machine.
Hot-water extraction can be an excellent method when it is performed correctly.
But two factors are particularly important:
temperature and pressure.
Too Much Heat Can Be a Problem
Many carpets contain yarn that has been twisted and heat-set to produce a particular appearance.
Excessive heat, particularly when combined with aggressive agitation, can contribute to distortion in susceptible carpet fibers.
That doesn’t mean hot-water extraction should be avoided.
It means that the temperature needs to be appropriate for the particular carpet being cleaned.
More heat is not automatically better.
Too Much Pressure Can Also Be a Problem
Pressure is another important consideration.
If too much water and pressure are used, excessive moisture can penetrate deeply into the carpet and its backing.
This becomes particularly important when a carpet contains jute in its backing.
When jute becomes excessively wet, it can release lignins and other natural components of the plant fiber. As the carpet dries, this can produce a yellow or brown discoloration that can migrate toward the surface.
This is sometimes described as a form of cellulosic browning because jute is a plant-based cellulosic material. However, there is an important difference between jute-related discoloration and the more common browning that can occur with materials such as cotton.
The difference can be particularly significant when the carpet is wool.
Browning associated with cotton or other cellulosic materials can often be treated successfully with an appropriate acidic rinse.
Jute-related yellow or brown discoloration, however, can be considerably more difficult to correct. In many cases, the same acid treatment that can remove cotton-related cellulosic browning will have little or no effect on discoloration caused by jute.
This is one reason I have always believed that controlling moisture is extremely important.
Once excessive moisture reaches a jute-containing backing, you can create a problem that wasn’t there before the cleaning began.
Why I Prefer a Portable Extraction Machine for Many Residential Carpets
There is a common belief that the most powerful carpet-cleaning machine must automatically produce the best cleaning.
I don’t agree.
For many residential carpets, I prefer using a portable extraction machine because the operator has very consistent control over the pressure and amount of water being applied.
A portable machine still provides sufficient heat, pressure and extraction to properly clean the carpet, while reducing the likelihood of overwetting.
That doesn’t mean truck-mounted machines are bad equipment. They can be excellent machines when operated properly.
My point is simply that maximum power isn’t necessarily the same thing as the best cleaning.
The objective is not to put as much heat, pressure and water into the carpet as possible.
The objective is to use the right amount.
The Cleaning Chemistry Matters Too
The equipment is only part of the cleaning process.
The chemistry matters.
Different carpet fibers, dyes and soils can react differently to cleaning agents, pH and temperature. The cleaning solution that is appropriate for one carpet may not be appropriate for another.
This is where understanding the material becomes just as important as understanding the equipment.
A professional cleaner needs to consider the fiber, construction, dye stability, amount and type of soil, previous cleaning history and the condition of the carpet before deciding what chemistry and cleaning procedure to use.
More chemical isn’t necessarily better.
More heat isn’t necessarily better.
More pressure isn’t necessarily better.
More agitation isn’t necessarily better.
Good cleaning is about using the right combination of all of these factors.
Area Rugs Are a Completely Different Challenge
When it comes to area rugs, the situation becomes considerably more complicated.
There are so many different types of rugs that it is impossible to assume that one cleaning method will work for all of them.
A rug may contain wool, cotton, silk, rayon, viscose, synthetic fibers or combinations of different materials.
It may have natural or synthetic dyes, a particular foundation, decorative borders, fringe or specialized construction.
Some rugs require blocking after cleaning to restore their proper shape.
Needlepoint rugs may require special handling.
Other rugs can have problems involving dye migration, shrinkage, foundation distortion, fiber damage or color bleeding if they are cleaned improperly.
This is one of the reasons I believe many area rugs should be professionally cleaned in a secure, controlled plant environment, where the technician can properly inspect the rug and determine what special requirements it may have before cleaning begins.
Experience With the Equipment Matters
There is another factor in professional cleaning that cannot be measured simply by looking at a machine: experience.
Every professional cleaner eventually becomes very familiar with the particular equipment and cleaning system he uses.
The more experience he has with that system, the better he understands how it responds to different carpets, how much pressure to use, how much moisture to apply, how quickly a carpet will dry and how much agitation is appropriate.
That experience is valuable.
But there is another side of experience that is just as important.
You need experience with the material you are cleaning.
Every type of carpet has unique characteristics.
The same is true of area rugs, and with rugs the differences can be even greater.
A technician who has spent years cleaning synthetic residential carpet may be extremely skilled at that type of cleaning but have much less experience with a hand-knotted wool Oriental rug.
Likewise, someone who routinely cleans commercial looped carpet may be very comfortable using vigorous mechanical agitation but may not have the same experience with a delicate residential cut-pile carpet.
These differences matter.
Routine Cleaning Is One Thing. Specialty Stains Are Another.
Routine cleaning can become relatively predictable for an experienced technician.
He sees the construction, identifies the fiber, evaluates the soil and condition, and selects a cleaning procedure based on what he is seeing.
But when you introduce a specialty stain, the situation can change dramatically.
A stain isn’t simply a stain.
The technician needs to consider what caused the stain, what the fiber is made from, what dyes were used, how the material was constructed, what previous cleaning chemicals may have been used and how that particular fiber will react to the treatment.
A stain-removal procedure that works beautifully on one carpet can create a permanent problem on another.
And this becomes even more complicated with area rugs.
A technician may be dealing with wool, silk, cotton, viscose, synthetic fibers or combinations of several materials. There may be different dyes throughout the rug, a foundation that reacts to moisture, a border that requires blocking or a previous repair that changes how the rug should be handled.
Then you add a difficult stain.
That is when experience really matters.
Someone who has worked with the same types of rugs and encountered the same types of stains repeatedly over many years develops an understanding that simply cannot be learned from an instruction sheet.
Sometimes the correct answer is knowing exactly what to do.
And sometimes the correct answer is knowing what not to do.
That may be one of the most important lessons I have learned in more than 55 years in this business.
So, Can Professional Carpet Cleaning Damage Your Carpet?
Yes—but the problem isn’t professional cleaning itself. The problem is using the wrong cleaning method for the particular carpet or rug.
A cut-pile carpet isn’t a loop-pile carpet.
A commercial loop carpet isn’t a residential twisted cut-pile carpet.
A wall-to-wall carpet isn’t an Oriental rug.
And an Oriental rug isn’t a needlepoint rug.
Each one can have completely different requirements.
The most important part of professional cleaning often happens before the equipment is turned on.
The carpet or rug needs to be identified, inspected and evaluated. Then the cleaning method, agitation, temperature, pressure, cleaning agents and amount of moisture should be selected accordingly.
After more than 55 years in this business, I believe professional cleaning isn’t about using the most powerful equipment possible.
It’s about knowing what the material can safely tolerate—and knowing how to clean it properly.
The most important piece of equipment a carpet cleaner has isn’t the truck mount, the portable machine or the rotary machine.
It’s the knowledge and experience to know what to do before the machine is turned on.
— Alec Houle
Alec’s Carpet & Upholstery Cleaning LLC
Serving the Greater Boston Area, South Shore and Cape Cod