# Class III standpipe-dry vs. wet question



## Truck3capt (Jun 2, 2017)

I have a designer that has proposed a Class III standpipe system for a 4-story Type I ,  B Occ, structure.  The first two floors are open parking garage subject to freezing.  The two upper floors are general office space.  The top of the 4th floor is 34' above the lowest level of fire dept. access. We're working from the 2012 IFC/IBC.

The locations provided meet the NFPA standard, but they are proposing that the entire system be a manual dry system based on the language concerning locations subject to freezing.  

I don't think the intention is to allow the exception for the dry system throughout the building just because the two parking garage levels are subject to freezing, but I haven't found any commentary anywhere that tells me that specifically unless I'm missing something in the IFC or NFPA 14.  

I assumed two separate systems, one for the garage and  one for the conditioned floors, or a dry valve in the conditioned space that supplies  the system in the garage.  Am I missing something?


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## cda (Jun 2, 2017)

Of course

What does it matter

Is the building sprinkled???

Not near the book it is quitting time and Friday

But if sprinkled it may not be required except in the garage



Where a standpipe is required in the code it will say "automatic" if automatic is required.  Which I think for sure high rise and maybe mall??


If a non required standpipe and you have no admendment saying this type is required, than it is what you can neogiate


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## cda (Jun 2, 2017)

Good article

https://sprinklerage.com/standpipe-systems-design-installation-requirements/


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## Truck3capt (Jun 3, 2017)

Thanks, cda.  Sorry to drop that on a Friday afternoon. I've been tied up with the fire investigation side of the house for the last 24 hours and just now got back to this to respond.

The building will not be provided with a sprinkler system. The height above the level of FD access requires the standpipe system. I think the rub we're having is the designer's interpretation that the freezing of the pipes allows the dry system throughout.  It doesn't help that this building will be connected to an existing building of almost identical construction  with a sky bridge.  That building has a manual dry standpipe.  I'm not sure how it happened, but that's been part of the discussion too.


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## cda (Jun 3, 2017)

What section are you using to require it?


Not a designer or engineer


Well if you push for automatic, that may mean a fire pump


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## Truck3capt (Jun 3, 2017)

905.3.1 Height. Class III standpipe systems shall be
installed throughout buildings where the floor level of the
highest story is located more than 30 feet (9144 mm)
above the lowest level of the fire department vehicle
access, or where the floor level of the lowest story is
located more than 30 feet (9144 mm) below the highest
level of fire department vehicle access.
Exceptions:
1. Class I standpipes are allowed in buildings
equipped throughout with an automatic sprinkler
system in accordance with Section 903.3.1.1 or
903.3.1.2.
2. Class I manual standpipes are allowed in open
parking garages where the highest floor is located
not more than 150 feet (45 720 mm) above the
lowest level of fire department vehicle access.
3. Class I manual dry standpipes are allowed in
open parking garages that are subject to freezing
temperatures, provided that the hose connections
are located as required for Class II standpipes in
accordance with Section 905.5.

My interpretation would be that the two lower levels of open parking subject to freezing could be Class 1 manual dry, but the 3rd and 4th floors that have office space would need to be a class III automatic wet based on NFPA 14 -10 below:

5.4.1.4 Class I standpipe systems shall be wet systems except
where piping is subject to freezing.
_5.4.2 Class II and Class III Standpipe Systems. Class II and
Class III standpipe systems shall be automatic wet systems unless
located in a facility where piping is subject to freezing and
where a fire brigade is trained to operate the system without 
fire department intervention, in which case an automatic dry
or semiautomatic dry system shall be permitted._
5.4.2.1* The automatic portion of a Class III system shall be
permitted to be only what is required for a Class II system
unless the Class I portion requires an automatic water supply.

Unless the cubicle dwellers are a trained fire brigade with access to high pressure service water and hose to supply the FDC.


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## cda (Jun 3, 2017)

Will have to read thru IFC

That is the driving code, no matter what 14 says.

At least that is what I would argue.


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## cda (Jun 3, 2017)

ok after reading reading and reading, and having to de cypher the standpipe requirements, because we are getting hit by them,

Yes appears in an enclosed building, when required because of height, a class III is required, and  required to be automatic.


Double check one thing on your project:::

""""The top of the 4th floor is 34' above the lowest level of fire dept. access""""

What is the distance from where the fire truck parks to the """"bottom""" of the top floor???


Look at the example on the fourth page:::


http://www.campusfiresafety.org/Por...ternational Code Council/Feb13-Codecorner.pdf


Good luck, like I said I am having to relearn standpipes also,


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## Truck3capt (Jun 3, 2017)

Thanks again.  I'm having to dig deeper into the standpipe requirements on other projects right now also.  I'll take a look at the reference you linked.  The 34' is from the top of the first level of the parking garage at grade to the top of the finished 4th floor.  Our access in the parking appears to be slightly lower based on what I know about the site.  That said I haven't seen any final grading or drainage plans to confirm the final elevation of the paving.


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## cda (Jun 3, 2017)

Not sure on having two standpipe systems

Might help the installer, if it winds up being automatic in the building.

Unless the water pressure is say less than 100 or so


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## Truck3capt (Jun 4, 2017)

cda said:


> Not sure on having two standpipe systems
> 
> Might help the installer, if it winds up being automatic in the building.
> 
> Unless the water pressure is say less than 100 or so



Good point.  I'd probably prefer one system for simplicity for our suppression crews with a dry valve for the system in the garage. One FDC for the entire building simplifies things.  I haven't seen any recent flow data yet so that might play into it too.


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