Installers’ tasks vary according to whether they specialize in the installation of carpets or resilient floor coverings. Some workers install both types of coverings. For any type, the preparation of the surface beneath the finish material is very important. The sub-floor surface must be firm, dry, smooth, and free of loose dust and dirt. Installers may have to sweep, scrape, sand, or chip dirt and other irregularities from the floor, as well as fill cracks with a filler material. Sometimes a new surface of plywood or cement must be laid down before any floor covering can be installed.
Experienced installers must be able to gauge the moisture content of the sub-floor and decide whether conditions are suitable for installing the covering. They should also know about the various adhesives that can be used, depending on conditions. Once the sub-floor surface is prepared, installers consult blueprints or sketches and carefully measure the floor to determine where joints and seams will fall.
When the layout is clear, the installers, often with the help of apprentices or assistants, measure and cut the covering to create sections of the proper size. They also cut and lay foundation materials such as felt on the sub-floor. With chalk lines and dividers, installers lay out lines on the foundation material to guide them in installing the floor covering. They trowel on adhesive cement and lay the floor covering in place, following the guidelines. Installers must be especially careful to align the pieces if there is any pattern in the flooring.
They must also pay particular attention to fitting the pieces in odd-shaped areas around door openings, pipes, and posts. To make tight seams where sections of sheet covering must join, they overlap edges and cut through both layers with a knife. After the covering is laid in place, they often run a roller over it to smooth it and ensure good adhesion.
When installing wall-to-wall carpeting, carpet layers measure the floor and plan the layout. They allow for expected foot-traffic patterns so that the best appearance and longest wear will be obtained from the carpet. They also must place seams where they will be least noticed.
Installers must make sure that the floor surface is in the proper condition and correct any imperfections that may show through the carpet. Some carpet can be tacked directly to certain kinds of floor, but in many buildings, including most residences, installers often use a tack-less method of laying carpet. A tackless strip is a thin strip of plywood with rows of steel pins projecting upward from it to grip carpeting firmly in place. Installers nail tackless strips around the border of the floor. Next, they cut and place padding in the open area of the floor.
Carpet often comes in 12-foot sections, so larger rooms require sections of carpet to be seamed together. They may sew the seam with a curved needle and special thread or use a heat-activated adhesive tape and an electric heating tool, like an iron.
When pieces are cut and ready, installers position the carpet and stretch it with special tools so it fits evenly on the floor, without lumps or rolls. They fasten it in place and any excess material is trimmed off so that the carpet meets the wall and door thresholds with a snug, exact fit.
Carpet installers use hand tools, including mallets, staple guns, pry bars, trowels, carpet knives, and shears; measuring and marking devices, such as tape measures, straightedges, and chalk lines; and power tools, such as stretchers.