Metals, Glass and Plastics as Building Materials

1. The history of building in iron and steel is hardly more than a hundred years old. The construction of the first railways has given considerable impetus to cast and wrought iron production. The commonest quality of steel for building construction is that known as mild steel (m.s.). Several qualities of high tensile steel are widely used everywhere. They vary both in their chemical composition and their mechanical properties. The elements used for most steel structures are the hot-rolled sections, produced in a great variety by the rolling mills.

2. Aluminum is the most important of the light metals used in the building industry. Magnesium is still lighter, but it has not yet become a building material. It is only used as an alloying metal in conjunction with aluminum. The major characteristics of aluminum in which the architect is interested are its durability and its light weight.

3. Glass is now generally employed in the construction of industrial buildings, office blocks and schools. In recent years it has eclipsed all other materials for heat and sound insulation purposes.

4. Plastics are a new building material. Nearly all the plastics are compounds of such simple elements as carbon, hydrogen, oxygen and sometimes nitrogen. The characteristics of the various plastics depend upon the way in which these elements are combined. Plastics are used where the older materials are not satisfactory, or for the development of entirely new uses. Since plastics combine all the fine characteristics of a building material together with good insulating properties, and are fireproof as well, it is no wonder that the architects and engineers have turned to them to add color and beauty to modern homes and offices.