Fireproof Buildings. A PLEA FOR FIRE-RESISTING METHODS OF CONSTRUCTION.

Progress, Volume II, Issue 2, 1 December 1906, Page 44

Fireproof Buildings. A PLEA FOR FIRE-RESISTING METHODS OF CONSTRUCTION.

In the September number of the Engineering Magazine there is an interesting article by Mr. Joseph K. Freitag on fire losses in the United States. It is suggested ,of course, by the San Francisco disaster, but deals with problems of importance to the whole building world. The author shows that the loss of life and property in the great dramatic catastrophe, which so startled the world, is equalled by the regular annual aggregate of similar losses in the United States, and much of this loss he thinks is preventable. The remedy for these great losses in life and property is not to be found, the author thinks, in either increased insurance, or in improved methods of fire fighting. Insurance is a palliative, and not a cure, and the same may be said of fire departments. Neither reaches deep enough to effect the removal of the cause, and make impossible fires of any degree of magnitude. Of course, fire-fightmg facilities will always be required to cope with incipient fires but the true underlying remedy for this great loss of life and property must lie in the universal application of fire-resisting methods to building construction — not in mercantile buildings in con-

gested city areas alone, but in all schools, churches, places of amusement, hospitals, town halls and even in city and country residences.

Fire-resisting Construction to be Universal. For the efficiency of fire-resisting construction vanes with the universality of its adoption. No building can be considered as a unit, regardless of its neighbours, for as long as a modern fireproof (or fire-resisting, as it is now generally called by fire protectionists) building stands in the midst of highly dangerous inflammable neighbours, just so long is the term fireproof a misnomer, and highly misleading to the layman who thinks that because termed " fireproof " the structure is therefore proof against all fire damage to itself or to its contents. This was well exemplified in the Baltimore fire, where the structures which had been built after fire-resistmg methods were found to have been gutted by fire, and to have sustained great damage, although still standmg and capable of being re-used, at least as far as essential structural portions were concerned. But it must be remembered that no building erected of the materials which Nature has given us to use can be designed or constructed to withstand conflagration at its height.

Fireproof Cities Needed. Fireproof buildings must stand in fireproof cities, for each added example of fire-resistmg construction contributes just so much to the bulwarks protecting all. We know by ample experience that buildings can be and are being constructed which will safely withstand all that can reasonably be expected of them as to fireresistance — namely, that under any ordinary conditions they will safely confine fire within the edifice or compartment where it ongmated, or safely exclude fire from any exterior hazard of not too great intensity. Their ability to fulfil these conditions has been fully demonstrated, both by buildings threatened by destruction from without, where the construction has prevailed against the attack, and in other cases where the fire resistance of the structure served to confine an otherwise dangerous fire to the compartment where it originated, almost without the knowledge of other occupants of the building. But individual examples are not sufficient. The practice of fire resistance must be so universal in building construction that no conditions could result in the spread of fire beyond the original premises, or at least, beyond immediate neighbours. Both the Paterson and Baltimore fires plainly demonstrated the ability of adequate fire-resistmg structures to obstruct even conflagration m its path.

Europe and America Compared. The author proceeds to compare fire losses in American cities with cities in England and Europe, to the great advantage of the latter. In American cities the fire losses are much greater than m most European cities, and this in spite of the fact that the daily number of fires is about the same, and in spite of the unusually marked superiority of American fire-fighting facilities. The real reason for the difference is to be found m the methods of building construction, While American cities have permitted the erection of " fire- traps " on every hand, Continental municipal regulations limit the height and area of buildings, and the character of the building materials, and generally enforce adequate fire-resistive construction throughout all city buildings. In Europe it appears fires seldom spread beyond the building in which they originate whereas, in America, a small fire rapidly becomes a wide-spread' conflagration. Mr. Freitag takes, by way of example, the Spanish city of Malaga, where the fire losses in 1890 amounted to but ;£ 1,000, with a population of 135,000 persons. The entire fire department was most primitive, about equal to what would be found in a small American town, say, fifty years ago; yet the pievalent mode of building of brick, stone, and iron, with heavy firewalls between all buildings, has accomplished this most insignificant fire loss.

Supply and Cost of Material. Naturally the scarcity of lumber for building purposes, and its consequent high price, has had much to do to bung about this status of building

methods ; while in the United States lumber has been available, cheap, and most readily adaptable to building uses. But, tortunately m this respect at least, lumber has been steadily advancing m price until some grades have increased as much as 1 50 per cent, during the past few years, while steel, brick, stone, cement, and the clay products have been gradually decreasing in price, until there are good commercial, as well as civic, reasons to hope that the hitherto Utopian accomplishment of universal fire-resistmg construction may soon replace the era of jig saw and wood frame. Independent of the added element of security against fire, fire-resistmg construction of the proper materials will be found to be cheaper in the long run, decreasing repairs and insurance premiums, giving immunity from vermin, reducing the transmission of sound, and proving warmer m winter and cooler in summer than the older non-fireproof methods. At present prices adequate fire-resist-ing construction may be estimated about ten per cent, dearer than ordinary methods of building ; but as the deterioration of a well built example of the former type has been estimated to be but one-tenth of one per cent, a year, while that of an ordinary wood joist structure is nearly four per cent, a year, this initial difference is soon overcome The Case of San Francesco. It may be objected that the previous argument in favour of fire-resisting construction is all very well on general principles, but that it has no direct bearing upon the catastrophe at San Francisco, because, in this instance the loss was largely the direct result of earthquake. Even from the earliest accounts of the San Francisco fire this view may be rightly disputed, for reports so far received from the stricken city tend to show that comparatively little damage was done to the modern fire-resistmg buildings by the seismic upheaval. The principal earthquake damage undoubtedly resulted to the flimsy non-fireproof buildings, which, in falling to destruction, started ■t conflagration on every hand, through which the V'better buildings were made to suffer. San Francisco has long been known as a particularly hazardous fire risk, and insurance officials have even gone so far as to say that it only was the excellence of her fire department that prevented a conflagration long since. To quote from a description of San Francisco written in 190=; "In San Francisco, for instance, there is little being done to improve the standard of construction It is notoriously a wooden city, yet insurance rates are fairly low, because, forsooth, the fire department is so excellent. That is like extolling the advantages of a certain locality as a health resort. It may be miasmatic ; yellow fever may stalk amuck ; its houses and streets may be foul, but, glory be, its doctoib are skilful ! "

Fireproof is also Earthquake Proof. Had the construction been uniformly fire-resisting, what a different result might have followed. For it so happens that our present methods of fireproof building are, undoubtedly, the most effective possible against earthquake disturbances. Our city buildings at least, unless they are public monumental buildings, are seldom constructed, when made fire-resisting, of solid masonry. On account of the area occupied by the foundations and piers of the older, solid construction, on account of the added height permissible with steel construction, and also because of its rapidity of erection, nearly all fire-resistmg buildings of any magnitude are now built on the " skeleton " or " cage " construe-

tion, so called because the vital steel skeleton or framework, consisting of columns, girders, and floorbeams, when riveted together, partakes of the nature of a metallic bird cage — strong, rigid, and proof against distortion. The introduction of these methods in Chicago was the direct outgrowth of the necessities in the larger American cities for centralisation within limited business areas, thus requiring the extension of buildings into the air to secure added floor space. This need was also felt in San Francisco, and the last previous seismic disturbance of any severity in that city having occurred in 1868, the introduction of steel-skeleton buildings in Chicago and New York m the latter "eighties" immediately raised the question as to whether such construction could be made safely to withstand any earthquakes to which the locality of California might be subjected. The question was much discussed by architects, builders, and structural engineers, until, in 1890, the skeleton-construction Mills building was erected in San Francisco by Mr. D. O. Mills, as an evidence of his, or his architects', faith in the efficacy of this type of building. This faith was founded on the knowledge that steel frameworks of this character .can be so designed as practically to permit of bodily overturning before failing in any portion. Indeed, in very high narrow buildings, exposed to severe wind pressure, it is no uncommon thing to anchor down the windward columns against possible overturning. Hence, in localities subject to earthquake, the only serious danger would be in the construction or safety of the exterior masonry walls, and this is accomplished by tying m the brick or stonework by metallic anchors attached to the steel frame. The Mills building was soon followed by other similar structures, until, in 1897, the nineteen story Spreckels building was erected, 300 feet high ; and it is well to know that later accurate accounts completely show that these steel buildings were practically immune from earthquake damage, succumbing only to the wide-spread conflagration caused by the demolition of inferior, non-fireproof structures. The author concludes with a plea for the passing of more drastic building regulations by State legislatures. — Carpenter <S- Builder.