The two major types of carpet construction
are woven and tufted.
Woven carpet is manufactured on looms where all of the yarns are fed into the loom at one time and become woven carpet.
Tufted carpet is the most common method of manufacturing carpet today. Tufting machines contain hundreds of sewing needles, each treaded with yarn and moved though a backing fabric. A loop or tuft is formed as the needle is pulled out, and is held in place by the backing fabric.
Historically a heavy coating of latex was applied to the back of the fabric. In order to give dimensional stability to the carpet a second backing is applied. Choice of backing material may be rubber, jute, vinyl or polypropylene (also known as olefin).
Today polypropylene is used both as the primary and secondary backing. This makes the carpeting impervious to damage due to over wetting. Animal and vegetable fibers, such as jute, formerly used in carpets, when over wet would release a stain which wicked to the surface leaving a condition known as browning.
Carpets are available in both loop and cut pile. Loop pile means the surface yarns are woven into the body of the fabric and left uncut. Cut pile means the face of the carpet is composed of cut ends of the pile yarn.
Gauge and Stitch determine the number of tufts per square inch in a carpet. It is recommended that commercial carpet have a minimum of fifty six tufts per square inch.
Pile height has a significant effect on the maintenance and appearance of a carpet. A one inch height of pile will show more crushing and shading than a quarter inch pile height.
While many commercial installations of carpet use cut pile, the greatest retention of appearance and lack of pile shading indicate loop or uncut pile construction is the best for commercial use.