13. Walls and partitions Part I

Some important factors that influence the selection of the materials and construction of walls for buildings are the following:

Architectural Appearance. — Although the shape of an industrial building may affect its aesthetic value considerably, the exterior walls are generally the features that determine whether or not its appearance is pleasing. Of course, along with the texture, color, and pattern of the exterior surface of the wall material must be included the pilasters, paneling, and any other elements that contribute to the total effect of the ensemble. For example, a high, long, blank wall almost cer­tainly will be unattractive regardless of the nature of the surface of the mate­rial of which it is made. Vertical and horizontal offsets, changes in color and texture, arrangement of windows are some means whereby an architect may skilfully enhance the appearance of a structure.

Cost.— The cost of the material used for the solid portions of the exterior walls is usually a relatively small part of the total cost of a building; the difference in cost of one desirable material over that of a less desirable one is still less important. Nevertheless, the aesthetic effect produced by the structure is permanent and will con­tinue long after any reduction of initial expenditure is forgotten. The engineer should consider all impor­tant features, then make his choice.

Suitability of the wall material depends on the structure in which it is to be used, and its harmony with neighboring structures. It is difficult to define the quality be­cause of the varying uses to which structures may be put, the climate of the region, the availability of materials, insulating properties, and the different kinds of construction that may be desirable and practi­cable. For instance, a 60- by 200-ft. building with walls of neat yellow face brick may appear out of place among buildings with corrugated metal siding, not because the new building of itself is unsightly but because it emphasizes the difference between the new and the old. It is even more self-evident that a building with corrugated, galvanized metal siding may appear incongruous when set among others having attractive walls of red bricks, concrete, or stucco.

(2250 signs)

Part II

The selection of the materials and construction of walls for buildings is influenced not only by architectural appearance, cost and suitability. There are also some other factors such as:

Durability. — A wall covering need not last longer than the rest of the structure, or the purpose for which the structure is built. In general, the durability and weather-resisting qualities of the walls and roof determine the useful life of the building.

Strength. — Aside from wall-bearing structures and those erected in regions that are subjected to earthquakes, the strength of wall materials is seldom critical unless the structural supports are improp­erly designed, or the walls are too thin and tall. Resistance to wind should be provided for, and buckling of thin walls under their own weight should be prevented. It is the structural frame rather than the wall itself that should generally be relied upon to hold a thin, flimsy wall in place.

Weight.— The weight of a wall may be especially worthy of consideration when continuous windows are used, because the lintels and any beams must carry to the columns all the wall loads supported by these members. Heavy brick may add considerably to the cost of the framing.

Resistance to Fire. — Combustible materials, such as wood, may be well adapted to use as walls except for the hazard of fire; incom­bustible materials like steel may be fire-resistant although not truly fireproof. The dangers and the risks involved should be studied in each case before anyone makes his selection of the material to be used.

It is difficult for one to illustrate and compare all—or even nearly all — possible types of wall construction. A large amount of development and experimental work is being-carried on with the object of securing lighter, cheaper, and better walls than those that have hitherto been in common use. These will be especially important in tall, multistory buildings; lightness alone is not so important in factory buildings. Even in the case of indus­trial, structures, the use of prefabricated panels may bring about con­siderable changes in one's ideas of suitable construction.

(2150 signs)