Value of Concrete.
At the sixth annual meeting of the National Association of Cement Users, Emil G. Perrot, of Philadelphia, presented a paper, entitled “An Incident of Value of Concrete in Reducing the Cost of Insurance.” Mr. Perrot’s firm had occasion recently to build in the city of Camden, N. J., an elevated water tank resting upon a tall structural steel tower. This tank was in the heart of the city, immediately adjacent to two business properties, the owners of which were somewhat fearful of the disastrous effect which might follow an adjacent fire and the possible collapse of the tower. It was found that the insurance rates on this structure, with its unprotected steel column legs, would amount to about $500 per annum. It was figured, however, that each of the columns and horizontal members of the tower could be encased in concreate at a total expense of $4,000. This fireproofing was thereupon done. It will be noted that the $4,000 cost of fireproofing means an annual expense of $240 at a 6 per cent, interest rate, whereas the insurance of the tower would have cost $500. In addition, it is probable that the tower is so fireproof that a tire in one of the adjacent buildings would not harm it, although, if it had been left unprotected, the damage to the surrounding structures might have been very great. The total cost of the tower, with its fireproofing, was about $13,000.