Masonry Magazine April 1970 Page. 18
DESIGN AND CONSTRUCTION
Early in the design stages, building layout can be effectively employed in noise control. A multifamily residence building can often be planned so that areas with similar noise levels can be located adjacent to and above and below each other. In addition, closets, stairways and corridors can be used as buffer spaces to help provide insulation against airborne sound transmission between apartment units. Location of doors and windows is also important to noise control. Interior doors should be staggered on opposite sides of a corridor to reduce sound transmitted directly from one door to another. Windows should be located away from a common wall if possible and casement windows arranged so that when opened, sound will not be reflected from one window through the open window of an adjacent apartment.
All of the design elements that are employed in sound control proper layout, selection of walls, etc., can be made ineffective through poor or improper construction. Sound leakage will occur through any opening in a wall. An improperly fitted corridor door is a prime source of sound leakage, for example. An opening of only one-sixteenth of an inch around a typical door provides an open area of about 12 sq. in. This illustrates the importance of achieving good, tight construction where openings occur, and well compacted mortar joints in the masonry wall itself.
Between apartments units reduction in sound insulation will usually occur at piping and duct openings, back to back medicine cabinets and electrical outlets. Noise through piping, conduit and duct holes can be effectively controlled by isolating the element from the masonry wall using compressed, molded sleeves or tightly packing around the element with low density insulating material, and completely caulking with a resilient sealant, (Fig. 3).