A Few More Words About Carpet
By Bret Lowder
Floor Store VP and General Manager
Last week we gave you some basic information about carpet terminology, as well as the most commonly used fibers. Here is a quick overview of how they compare to each other in terms of quality and performance.
Quality Factors
The type of fiber used and the way the carpet is constructed determines the basic performance of the carpet. Quality can be enhanced by the way the fibers, or yarns, are twisted and heat set, and by the density of the tufts. Deep pile height that's densely tufted has a luxurious feel; however, pile height is really a matter of personal choice and does not, in itself, denote durability.
Performance Glossary
Density - Refers to the amount of pile yarn in the carpet and the closeness of the tufts. The denser, the better.
Twist - The winding of the yarn around itself. A tighter twist provides enhanced durability.
Heat-Setting - The process that sets the twist by heat or steam, enabling yarns to hold their twist over time. Important in cut pile carpet. Most nylon, olefin, and polyester cut pile carpets are heat-set.
Performance - Some manufacturers have a rating scale for choosing carpet for various traffic areas. See Performance Ratings below.
BCF and Staple - BCF stands for Bulked Continuous Filament, found only in man-made fibers. Staple means spun fibers, found in both natural and synthetic yarns.
In terms of durability, there is little difference between bulked continuous filament (BCF) or staple (spun) fibers. The difference lies in the length of the fibers in the yarn. Staple has shorter lengths, giving the yarn more bulk (sometimes described as being more like wool).
When carpet is manufactured with staple fiber, there will be initial shedding of shorter fibers. It will soon stop, depending on the amount of foot traffic and frequency of vacuuming. Wool is a naturally staple fiber; nylon and polyester can be staple or continuous filament; and Olefin (polypropylene) is usually BCF.
Performance Ratings
Although not all manufacturers/retailers provide this numerical rating, those who do believe it to be useful to the consumer in making an appropriate selection for the particular area under consideration. For instance, a larger family with heavy traffic through narrow traffic lanes, such as a hallway, would need a carpet with a high performance rating in that area. On the contrary, a small family looking for a carpet for a guest bedroom may wish to choose a carpet with a lower rating. If the manufacturer does provide a performance rating, it will be displayed on the label.
Performance ratings incorporate a change-in-appearance number on a 1 to 5 scale: 5 is no change and 1 is very severe change. The performance rating indicates the amount of surface appearance change to be expected in major traffic areas during the first year of service for a typical four-person household. A carpet with a higher performance rating (such as 4 or 5) is one that will maintain its new appearance longer in various traffic conditions than one with a lower performance rating. A 2 to 3 rating is good for areas with less traffic.
The numbers are determined in carpet testing laboratories, utilizing a standardized mechanical laboratory test based on human walkers trafficking (walking) on carpet for a specific number of steps (traffic counts). After the specified traffic counts are completed, the samples are visually graded by comparison with Appearance Change Grading Scales supplied by the Carpet and Rug Institute.
