The Golden State: Where & How to Live, Secure, Visit, Enjoy and Thrive in California
First Aid For The Ailing Houses
The purpose of acoustical material is to trapthe sound waves so they will not be reflected. To keep them from bouncing off, most acoustical material is designed to allow them to pass through—and thus into the rest of the house.
To prevent sound from reaching the rest of the house, one of the simplest ways (and by far the least expensive) is to install a layer of insulating material of the mineral-wool type between the joists before the ceiling is applied. This material has a low sound-transmitting ability and will trap a greater part of the noise. Joists will carry some of the sound, however, and if the ceiling is nailed directly to these joists, soundproofing will not be complete. Furring strips should be nailed across the joists, and the acoustical or other ceiling material nailed to the strips rather than directly to the joists. However, the small extra space needed may make the ceiling un- comfortably low.
Walls When a room in the basement is finished, the walls should be decorated and, as these are usually poured concrete or cement block, they must have special treatment. When the walls are rough or uneven, they should be smoothed and leveled. Small roughness, like the ridges on poured concrete left by the forms, can be rubbed down with a carborundum brick, which can be had at a paint or hardware store or from a dealer in mason's materials.
When this rubbing will not be enough, the walls should be made smooth by a coating of cement plaster. With a stiff wire brush, all loose particles should be removed. Then they are washed with plenty of clear water, not only to clean them, but to get the walls soaking wet. While wet, they are painted with a mixture of portland cement and water to the consistency of thick paint, applied with a wide brush. This is immediately followed by a plaster made of 1 part of Portland cement and 3 of clean, sharp sand, thoroughly mixed with water to a stiffness that can be troweled. This plaster is spread on with a large mason's trowel, leveled by rubbing with a piece of flat board, and given any finish that play be desired, smooth or textured. This coating should not be allowed to dry quickly; the more slowly it dries, the harder and firmer it will be. It should be frequently sprinkled and protected by hangings of tarpaulin, burlap, carpet, or some other thick fabric. This should be continued for four days, although a week would be better.
