Hi,

I'm a member of the New York City chapter and I have a colleague in London, England who has a project in Chicago.

They are designing a 2000 ft. tower and in his scheme, he wants to place a 130,000 gal. suction tank in the basement to feed standpipes and sprinklers halfway up. He is concerned about the weight of an intermediate tank feeding the second half, so he wants to know if it is possible to feed the intermediate tank, sized only for 26,000 gallons, with the basement fire pumps supplying makeup.

Just offhand, I don't think this can be done. He mentioned sizing the tank for 2 hours of supply. Here in NYC, we size the tank for 20 or 30 minutes of supply only. 2 hours seems like alot.

Can anyone advise the requirements in Chicago for high rise structures. I advised my friend that they need to buy a code and see what is required, but if I can get some info in the interim, that would be helpful.

Regards and see you in Tampa!

Tony Curiale
Buro Happold Consulting Engineers