Q.: I plan to build a house on one of the Florida keys. The code requires the house to be built 8 feet above the waterline, so new houses are built on stilts. What literature or guidance can you give me on the proper steel to put in concrete pilings and in the concrete for the first floor? I also need guidance on the number of piles, spans, floor thickness and reinforcement. I have not been able to find the information or rules of thumb in homebuilder or handyman books and publications.
A.: This type of construction is something for which it is not possible to simply supply rules of thumb or instructions for the handyman. You might wish to begin by looking up the local requirements for the area. Then you might wish to obtain a copy of CRSI Handbook, an 850-page book available for $32.95 from Concrete Reinforcing Steel Institute, 180 North LaSalle Street, Chicago, Illinois, 60601. This is a collection of tables and formulas for reinforced concrete design. Then you might apply the data from the handbook conservatively for a heavier design load.
You might also be interested in the Problem Clinic item "Sound the Alarm," CONCRETE CONSTRUCTION, June 1981, page 532, telling of the necessity of providing adequate cover over the steel in concrete exposed to ocean spray.