Although often omitted in basements, a ceiling improves the appearance, does away with numerous corners and spaces between joists where cobwebs and dust collect, and prevents dust from passing through the first-story flooring to the rooms above, especially where the floors are of a single thickness.
Of far greater importance, if the ceiling is of tight-fitting fire-resistant materials, is the safety it affords by delaying the spread of basement fire to floors above and by reducing smoke damage.
If the basement is dry and well-built, it can often be made more attractive by installing a ceiling and painting the walls and floor. If the concrete floor is dry, it may be covered with asphalt tile to give a smooth, attractive floor which can be maintained with the minimum of effort by waxing.
Before putting on the ceiling, all openings through which fire might find quick passage to the structure above should be adequately fire-stopped. Such openings may be found around service pipes and registers and between joists or studs where they join the foundation. It is best to use incombustible materials for fire-stopping, such as crushed refuse mortar, plaster, concrete, hollow tile, gypsum block, broken brick, or other similar material that contains sufficiently fine particles to fill the voids. The firestopping can be supported by horizontal wood strips, not less than 2 inches thick, or by metal or wire mesh.
Several materials are used for ceiling purposes: Gypsum or asbestos board, plaster on metal lath or on gypsum plaster board, or properly furred metal ceiling may be used, depending upon the taste of the individual and the amount of money to be spent.
Material within 2 feet of the top of a boiler or furnace, or within 1 foot of a smoke pipe, should be protected by a loose-fitting metal shield, arranged to give an air space of 1 or 2 inches between the metal and the wall surface. The air space may be provided by using ‘ small blocks of incombustible material between metal and joists, or by suspending the metal sheets on wires or hooks fastened to the joists. If tin is used for a shield, it should have locked joints, since soldered joints are not reliable. Similar protection should be placed over any woodwork or wood lath and plaster partition, within 4 feet of the sides or back, or 6 feet from the front, of any boiler, furnace, or other heating equipment. This covering should extend at least 4 feet above the floor and at least 3 feet beyond the heating device on all sides.