Gypsum board finish levels speaks to what are gypsum board finish levels and why gypsum board finish levels.
They are standardized and have been developed by the Gypsum Association and are also specified in ASTM C840. These enable the designer to specify quickly and simply the minimum level of finish that is acceptable for any project or portion of a project.
Level 0, the minimum, consists of just the boards, without taping, finishing or accessories. It is usually used only for temporary construction or where finishing is postponed until a later date.
Level 1 requires that only joints be covered with tape set in joint compound. Its primary use is in areas of the building that are not open to view, such as above ceilings, in attics and in service corridors. Level 1 is also the minimum finish level for fire resistance rated gypsum board assemblies, in which applications it may also be referred to as fire taping.
Level 2 adds to a level 1 finish a coat of joint compound over the accessories and fasteners. After joint tape is set in compound, these joints are also immediately wiped with a joint knife a second time to add a thin coat of compound over the tape. A level 2 finish is appropriate in garages, warehouses and storage areas and for boards used as a backer for ceramic tile.
Level 3 adds a full second coat of compound over tape, accessories and fasteners after the first coat has dried. It is intended for surfaces that will be textured or covered with heavy wall coverings.
Level 4 is designed for surfaces to be finished with flat paints, light textures or thin wall coverings. It adds a third distinct coat of joint compound over taped seams, fasteners and accessories.
Level 5 the highest, adds a very thin skim coat of joint compound over the entire surface of the board. The skim coat has no measureable thickness, because its purpose is only to fill pores and low spots in the wall to produce a very smooth surface. It is recommended for surfaces that will receive gloss or semigloss paints and for surfaces that will be lit in such a way as to cast shadows that can highlight even slight imperfections.
Plasterers and drywall finishers often work on stilts to avoid having to erect and move scaffolding. The stilts, which are strapped to the legs of the workers, are very sophisticated, stable devices that keep the worker’s foot fully supported and parallel to the floor.