It’s not just choosing the right color, anymore. There are now dozens of kinds of fibers in residential carpet. How do you decide what’s best for you?
Wool has been used to make rugs for thousands of years. Heirloom rugs, ones that are handed down from generation to generation, are made with wool. Throwaway rugs, ones you buy for a theme or for color; ones that don’t last very long, are not made from wool. Wall-to-wall carpet must have the same long-lasting properties as a good rug. Because wool fiber has a natural twist (like a corkscrew) it will bounce back after long and heavy use. But the twist in a synthetic fibers is created using heat, so friction (like walking) and external heat (like steam cleaning) will untwist a synthetic. While synthetic fibers are transparent, like a window, wool is opaque, like a wall. If you have soil on one side of your window you can see it from either side. But the opaque wool hides soil that is on the far side of the fiber. Modern synthetic fibers are molded in shapes to re-direct light so they also hide soiling.
Wool has tiny scales along the outside of every fiber. Dry soil clings to these scales and is held at the top of the carpet so it can be easily removed by regular vacuuming. Synthetic fibers are slippery so dry soil slides down the fiber toward the bottom of the carpet. That is why vacuuming with agitation (a beater bar or a bar with brushes) is needed to get dry soil out of synthetics. Wool traps airborne contaminants and pretty much holds them forever.
Wool is inherently flame retardant. Being the hair from sheep, wool is a renewable resource. Wool can absorb up to 30% of its weight in water vapor (vapor, not liquid like spills). This makes wool carpet fluff up – rejuvenate itself – when it is steam-cleaned. A synthetic fiber will absorb no more than 1% to 6% and a flattened-down synthetic will generally stay flat. While wool can absorb vapor, it has a membrane that sheds liquid water along with any stain that might travel with the water. Wool is a great insulator, feeling warm in the winter and cool in the summer. When wool holds water vapor it is also less able to create static electricity. Wool is soft to the touch but strong under foot.
Modern wool carpet is moth proofed and an amazing property of that moth proofing is that crawly bugs, like scorpions, cannot get across a room of wool carpet without being “proofed” also. Wool fibers are short – no longer than the hair of the sheep they came from. Several different processes are used to make them stay together [more of that in the next chapter] but in general it is the scales of the fibers that lock together to hold them tight. As fibers on the top of the carpet get damaged or badly soiled, they slip free from their neighbors and are swept up into the vacuum. Thus, wool shedding is a good thing, making for a fresher, cleaner surface with each vacuuming. Synthetic fibers are long (sometimes hundreds of feet long), like a fishing line, and tenaciously stay part of the carpet even when they are soiled, flattened or ugly. A good wool carpet will just wear out after many years. Most synthetic carpets will “ugly out” early but just never wear out. Wool carpet truly wears with elegance.
Next Chapter: Wool’s other side.