11.47.1 Wood Windows These can be used for most types of construction and are particularly adaptable to residential work. The most important factor affecting wood windows is weather exposure. However, with proper maintenance, long life and satisfactory service can be expected. Sash and frames have lower thermal conductivity than metal. The kinds of wood commonly used to resist shrinking and warping for the exposed parts of windows are white pine, sugar pine, ponderosa pine, fir, redwood, cedar, and cypress. The stiles against which a double-hung window slides should FIGURE 11.31 Dimensions for multiple modular openings for double-hung wood windows. be of hard pine or some relatively hard wood. The parts of a window exposed to the inside are usually treated as trim and are made of the same material as the trim. (See also Fig. 11.32.) 11.47.2 Steel Windows These are, in general, made from hot-rolled structural-grade new billet steel. However, for double-hung windows, the principal members are cold-formed from new billet strip steel. The principal manufacturers conform to the specifications of The Steel Window Institute, which has standardized types, sizes, thickness of material, depth of sections, construction, and accessories. The life of steel windows is greatly dependent on proper shop finish, field painting, and maintenance. The more important aspects of proper protection against corrosion are as follows: Shop Paint Finish. All steel surfaces should be thoroughly cleaned and free from rust and mill scale. A protective treatment of hot phosphate, cold phosphatechromate, or similar method such as bonderizing or parkerizing is necessary to FIGURE 11.32 Details of installation of double-hung windows. protect the metal and provide a suitable base for paint. All windows should then be given one shop coat of rust-inhibitive primer, baked on. Field Painting. Steel windows should receive one field coat of paint either before or immediately after installation. A second coat should then be applied after glazing is completed and putty set. Hot-Dipped Galvanized. Assembled frames and assembled ventilators should be galvanized separately. Ventilators should be installed into frames after galvanizing and bonderizing. Specifications must guard against distortion by the heat of hot dipping, abrasion in handling, and damage to the zinc galvanizing by muriatic acid used to wash brickwork. Painting is optional. 11.47.3 Aluminum Windows Specifications set up by the Aluminum Window Manufacturers Association are classified as residential, commercial, and monumental. These specifications provide for a minimum thickness of metal and regulate stiffness of the component parts, as well as limiting the amount of air infiltration. The manufacturers offer about the same window types that are available in steel. However, in addition to these standard types, substantial progress has been made in the development of aluminum windows as an integral part of the walls of a building. With the exception of ventilator sections, which are shop-fabricated, some windows are completely assembled at the job. The wide range of extruded aluminum sections now manufactured has made it feasible to treat large expanses of glass as window walls. Picture windows with many combinations of ventilating sash are also furnished in aluminum. Many features are available, such as aluminum trim and casing, weather stripping of stainless steel or Monel metal, combination storm sash and screens, sliding wicket-type screens, and metal bead glazing. Aluminum windows should be protected for shipment and installation with a coating of clear methacrylate lacquer or similar material able to withstand the action

Without edge beams With edge beams* Interior panels With drop panels Exterior panels Without edge beams With edge beams* Interior panels Ln Ln Ln Ln Ln Ln *Beams between columns along exterior edges;  0.8 for the edge beam. years or more, 1.4 for 12 months, 1.2 for 6 months, and 1.0 for 3 months, and 

compression-steel ratio, the area of the compression reinforcement A
, in.2, di- s vided by the concrete area bd, in2. The sum of the short-term and long-term deflections should not exceed the limits given in Table 9.14. Two-Way Slabs. Unless computations show that deflections will not exceed the limits listed in Table 9.14, the ACI 318 Building Code prescribes a minimum thickness for non-prestressed two-way slabs. For two-way slabs without interior beams, with a ratio of long to short span not exceeding 2, and with Grade 60 reinforcement, the Code requires that the thickness h be at least the fraction of the clear span given in Table 9.16. The thickness based on Table 9.16 cannot be less than 5 in. for slabs without drop panels nor less than 4 in. for slabs with drop panels. For two-way slabs having beams on all four edges, with m  0.2, the minimum thickness h should be based on the preceding criteria for two-way slabs without interior beams. For 0.2  m  2.0, the minimum thickness should not be less than L (0.8  /200,000) n y h
(9.68)

Temp,
F State City Temp, Ala. Birmingham 10 Miss. Vicksburg 10 Ariz. Flagstaff
10 Mo. St. Louis 0 Ariz. Phoenix 25 Mont. Helena
20 Ark. Little Rock 5 Nebr. Lincoln
10 Calif. Los Angeles 35 Nev. Reno
5 Calif. San Francisco 35 N.H. Concord
15 Colo. Denver
10 N.J. Trenton 0 Conn. Hartford 0 N. Mex. Albuquerque 0 D.C. Washington 0 N.Y. New York 0 Fla. Jacksonville 25 N.C. Greensboro 10 Fla. Miami 35 N. Dak. Bismarck
30 Ga. Atlanta 10 Ohio Cincinnati 0 Idaho Boise
10 Okla. Tulsa 0 Ill. Chicago
10 Ore. Portland 10 Ind. Indianapolis
10 Pa. Philadelphia 0 Iowa Des Moines
15 R.I. Providence 0 Kans. Topeka
10 S.C. Charleston 15 Ky. Louisville 0 S. Dak. Rapid City
20 La. New Orleans 20 Tenn. Nashville 0 Maine Portland
5 Tex. Dallas 0 Md. Baltimore 0 Tex. Houston 20 Mass. Boston 0 Utah Salt Lake City
10 Mich. Detroit
10 Vt. Burlington
10 Minn. Minneapolis
20 Va. Richmond 15 Accordingly, design outdoor conditions should be selected in accordance with the manner in which the building will be used and, just as important, to obtain reasonable initial cost and low operational costs. Outdoor design conditions for a few cities are shown in Tables 13.4 and 13.5. Much more detailed data are presented in the ASHRAE HandbookFundamentals. The use of outdoor design conditions does not yield accurate estimates of fuel requirements or operating costs, because of the considerable variations of outdoor air temperature seasonally, monthly, daily, and even hourly. These wide variations must be taken into account in attempts to forecast the operating costs of a heating