commonly made in lengths; sheets of and longer also are common. Thicknesses of plasterboard available are . Plasterboard is commonly made with one of three edge treatments: tapered edge, where the long edges of the board are tapered with a wide bevel at the front to allow jointing materials to be finished flush with the main board face; plain edge, used where the whole surface will receive a thin coating (skim coat) of finishing plaster; and beveled on all four sides, used in products specialized for roofing. Major UK manufacturers do not offer four-sided chamfered drywall for general use. Construction techniques As an alternative to a week-long plaster application, an entire house can be drywalled in one or two days by two experienced drywallers, and drywall is easy enough to be installed by many amateur home carpenters. In large-scale commercial construction, the work of installing and finishing drywall is often split between drywall mechanics, or hangers, who install the wallboard, and tapers and mud men, or float crew, who finish the joints and cover the fastener heads with drywall compound. Drywall can be finished anywhere from a level 0 to a level 5, where 0 is not finished in any fashion, and five is the most pristine. Depending on how significant the finish is to the customer, the extra steps in the finish may or may not be necessary, though priming and painting of drywall are recommended in any location where it may be exposed to any wear. Drywall is cut to size using a large T-square, by scoring the paper on the finished side (usually white) with a utility knife, breaking the sheet along the cut, and cutting the paper backing. Small features such as holes for outlets and light switches are usually cut using a keyhole saw or a tiny high-speed bit in a rotary tool. Drywall is then fixed to the structure with nails or drywall screws and often glue. Drywall fasteners, also referred to as drywall clips or stops, are gaining popularity in residential and commercial construction. Drywall fasteners are used for supporting interior drywall corners and replacing the non-structural wood or metal blocking that traditionally was used to install drywall. Their function saves material and labor costs, minimizes call-backs due to truss uplift, increases energy efficiency, and makes plumbing and electrical installation simpler. When driven fully home, drywall screws countersink their heads slightly into the