Standpipe Question

[MechEng2007]

We are installing a sprinkler system and standpipe in a 4-story hotel. The system is design/build and the local AHJ doesnt have much knowledge about sprinklers/standpipes.

Can I install a dry manual standpipe rather than a wet manual one? Floor control valves are not required and the local AHJ does let us install manual standpipes over automatic. Is there any code that requires a wet over a dry?

Also, I have always thought that NFPA 13 & NFPA 14 are very vague on combination standpipe/sprinkler risers. Do newer versions of NFPA 14 tackle this issue at all?

Thanks in advance. This board always has good information.

 

[PEDARRIN2]

Look in your building code.

There might be a height restriction for the dry manual.

NFPA 14 requires 100 psig at the top fire department valve - which might be on the roof if there is roof access from a stairwell.

Also check with your local fire department. If the height is too high and the local fire department doesn't have equipment able to produce enough pressure when they hook into the system, you may be required to provide a wet standppipe and a pump.

 

[SprinklerDesigner2]

These things vary so much between jurisdictions it is hard to say.

In some states, Georgia for example, manual standpipes are only allowed in open parking garages.

But there is a trade off. In buildings other than high rise automatic standpipes do not have to meet any pressure or discharge requirements as long as all the pipe is a minimum 8" diameter. Lots of 4 story motels with 8" standpipes in the stairwell but no fire pump.

 

[cdafd]

http://www.eng-tips.com/search.cfm?action=Search&pid=184&requesttimeout=75

do a seaqrch on this forum and put in standpipe and there are some answers to your question.


I think once you hit high rise you go wet, and also may depend on climate and ahj