BUILDING LAWS 357 



BUILDING LAWS, SPECIFICATIONS, 

 AND COST 



BUILDING LAWS 



The construction of reinforced-concrete buildings is regu- 

 lated by the laws of the municipality in which the work is 

 carried on. These building laws differ for each city. The 

 following laws are used in the City of Philadelphia. They 

 are among the latest and may be considered as a good 

 example. 



"The term reinforced concrete shall be understood to mean 

 an approved concrete mixture, reinforced by steel or iron of 

 any shape, so that the steel or iron will take up all the 

 tensional stresses and assist in the resistance to compression 

 and shear. 



"Before a permit to erect any reinforced-concrete structure 

 is issued, complete specifications and drawings shall be filed 

 with the Bureau of Building Inspection, showing all details 

 of the construction, size and position of all reinforcing rods, 

 stirrups, etc., and giving the composition and proportions of 

 the concrete. 



"The execution of the work shall be performed by work- 

 men under the direct supervision of a competent foreman 

 or superintendent. 



"Reinforced-concrete construction will be accepted for 

 fireproof buildings of the first class, if designed as herein- 

 after prescribed; provided, that the aggregate for such 

 concrete shall be clean, broken, hard stone, or clean, graded 

 gravel, together with clean siliceous sand or fine-grained 

 gravel; should the concrete be used for flooring between 

 rolled-steel beams, clean furnace clinkers entirely free of 

 combustible matter, or suitable seasoned furnace slag may- 

 be used; when stone is used with sand or gravel it must be 

 of a size to pass through a 1-in. ring, and 25% of the whole 

 must not be more than one-half the maximum size; and 

 provided further, that the minimum thickness of concrete 



