_Pre-fabricated Houses._--The field of house construction has been occupied almost exclusively by the individual architect or builder who has wrought according to the general ideas of the intending occupant or the real estate developer. When the plans are completed and approved, the contractor assembles the necessary materials from local sources, builds and equips the house and turns it over to the buyer in completed condition. Under such a procedure there is little application of mass production measures which have reduced costs and raised quality standards in many industries, notably in automobile construction, for example. Thousands of houses built to sell in the recent construction era of the 1920's have proved unsatisfactory and costly to the occupants as the result of shoddy building methods. Such methods seem to be typically American as distinguished from the far more solid and permanent Old World procedure. It now seems likely that the problem of economical and substantial housing will be met in the method that is also American--namely, by the pre-fabricated house to which various natural resources of the country contribute. The parts of such houses are made under mass production methods and easily assembled on the owner's lot. The same idea can be applied with ease to apartment house construction in any location. The first step in this direction has already been mentioned in the case of mail-order companies which cut the lumber to fit and supply every needed accessory to the last detail. The next step, and the one that bids fair to inaugurate an entirely new house-building procedure, is now in the making, although as yet it is in the experimental and testing stage. Examples of such construction made their first public appearance at the Century of Progress Exposition at Chicago in 1933. Materials that enter into the construction of these new-type houses include steel, asbestos, aluminum and cement. As a rule, the buildings have a steel frame erected on cement foundations and without a cellar; the walls and partitions are of asbestos composition and the roof constructed of steel sheets with aluminum insulation. Such a building is fireproof and proof also against vermin, lightning, wind and earthquake. The house is also adapted to and equipped with heating, lighting, plumbing and air conditioning facilities. The whole building is pre-planned and pre-fabricated as a unit with its component parts constructed under economical and interchangeable mass production methods. Modifications of the construction above mentioned include the use of sound-proofed steel panels or insulation board for partitions and walls with an exterior of painted steel. Many other modifications are being developed to insure individuality, stability, insulation and economy in first cost and maintenance. The lines of most of these houses are severe and modernistic in design, although decorative and unique effects are easily obtainable.