"In these same protected factories and warehouses, the actual fire and water loss is less than four cents on each one hundred dollars of insurance, and, being so small, it would seem that they must be almost impossible of reduction; but nevertheless it is possible.
"How can this be accomplished? This is the problem of the designer and builder of the concrete factory.
" (1) By avoiding vertical openings through floors— a common fault in many factories with wooden floors. To be a perfect fire cut-off, a floor should be solid from wall to wall, with stairways, elevators, and belts enclosed in vertical fireproof walls having fire-doors.
" (2) By provision for making floors practically waterproof, that water may not cause damage on floors below that on which fire occurs. Scuppers of ample size to carry water from floors to outside are an essential part of the design. In the ordinary factory with wooden floors, loss from water is almost invariably excessive as com pared with the loss by actual fire.
" (3) By making the buildings as incombustible as possible, thus reducing the amount of material upon which a fire may feed. Also by provision for sufficient thickness of fireproofing to insulate all steel work thor oughly, the fireproofing being sufficiently substantial that it may not scale off ceilings or columns at a fire or from other causes, thus allowing failure of steel work, by heat ing or deterioration. An owner is thus more secure if the fire protection or any parts of it fail at a critical moment.
" (4) By good judgment as to the extent or amount of fire protection required in each individual case. While the value of the automatic sprinkler is recognized and the general rules specify its installation, the Factory Mutual companies do not require it in the concrete build ing, except where there is sufficient inflammable material in the contents to furnish fuel for a fire. An essential feature of good factory construction includes not only consideration of the building, but protection adequate to its needs only.
"The extent to which the above is faithfully carried out, will eventually be the determining feature in the cost of insurance." G. C. Nimmons, a Chicago architect, has ex pressed the following views on the relation of concrete construction to fire insurance rates: "One of the strongest influences toward the increase of the number of concrete buildings nowadays comes from fire insurance companies. The Factory Mutual in surance companies of New England are strong advocates of reinforced concrete buildings for commercial and man ufacturing purposes. Not so much for any superior fire proof qualities of reinforced concrete, but on account of the superior waterproof qualities of concrete buildings. I believe it is a matter of record that the Factory Mu tuals of New England have paid more for water damage than for fire damage." forced Concrete Design