- THE MAGAZINE
Some of the most common questions asked by newbies and untrained cleaners about carpet cleaning center around carpets and rugs shrinking when cleaned. This is also a favorite subject for potential customers to bring up during site visits.
Actually, shrinkage in tufted broadloom carpets and rugs is, for the most part, a thing of the past. Shrinkage occurs in the backing or foundation materials, the result of natural yarns absorbing moisture and swelling. The swelling of the yarns effectively shortens the warp and weft yarns, causing shrinkage.
Confused by the terms warp and weft? Can’t remember which is which? Neither could I. In the early years I would say “warpandweft” real fast and hoped no one asked which was which. Then, after I had started teaching classes I had pretty bright student (who may or may not have been ISCT CEO Bill Yeadon) who said, “Gee Bob, it’s easy to remember the difference. The warp yarn runs the length of the goods, kind of like ‘warp speed Scotty,’ and the weft yarns run from side to side, or ‘wight to weft.’” Thank goodness for the student that teaches the teacher!
When I started in this business, tufted carpets had jute backings, sometimes both primary and secondary. Talk about shrinkage. Back in those days we did not really know about things like preconditioning before extraction cleaning, so we just kept going over the rug until it looked clean, dumping down more water with each pass.
With an improperly installed job, big problems could develop. For example, when an installation on a plywood floor used tackless stripping designed for concrete, the tack strip would pull out of the floor as the carpet shrank. There were also cases of poorly constructed seams that ripped apart as the carpet shrank.
The problems with shrinkage gradually started to go away with the introduction of synthetic yarns in the mid 1960s. As ActionBac polypropylene backings replaced jute backings, first in primary backings then in secondary backings, the problem of shrinkage in tufted carpets became a thing of the past. Today there may be problems with tufted carpets “growing” and rippling or bulging, but no more shrinkage. However, it is still good practice to inspect primary and secondary backing or foundation yarns of carpets or rugs you are preparing to clean to be sure what you are dealing with.
The issue of shrinkage may still raise its ugly head if you are working on woven rugs. When working with wovens it is important that you determine if the foundation yarns are natural, such as jute or cotton, or synthetic. Here is where burn testing becomes important.
Some cleaners may be experienced enough to make the determination by looking at the yarns. Others will have to actually perform the burn test to be sure. Synthetic fibers melt and leave a hard blob of melted plastic when burned, while natural fibers will char or smolder, leaving only a soft crumbly ash. ICS columnist Lee Pemberton teaches the concept of “clean fingers/dirty fingers.” When the ash of the burned fiber is crushed between your fingers, you will have clean fingers if the fiber is synthetic. If the fiber is natural, your fingers will be dirty.
With the explosive growth in loose decorative rugs, cleaners are encountering them more often than in the past. Here is where you may encounter the problem of “differential shrinkage,” a term describing a condition characterized by rippling or wrinkling around the edges of the rug. This is especially a problem with woven rugs that have a decorative border attached; the border shrinks and the main body does not, or vice versa. It is much easier to prevent this problem than it is to correct. One very good method of preventing differential shrinkage is to “block” the rug by temporarily attaching it to some sort of subfloor. Many rug-cleaning plants have an area in their plant where they can tack it down securely around the perimeter until it is dry. Always keep in mind the old adage “An ounce of prevention is worth a pound of cure” and a bit of wisdom from the great Barry Costa, “Inspect to know what to expect.” Just more justification for the site visit and a physical inspection of the products you are being asked to clean.
I hope that all of this will lessen any concerns about shrinkage problems. Until next month, I’ll see ya!