Where is the code section that states the numbers (calcs) on the supply side shall be greater than the numbers at the base of riser (system side)?
 
Does the code address this with a code section?

​Thanks in advance.

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Our high-rise facility consists of apartments, condominiums, retail on the bottom floor, restaurant tenants on the top floor, and (3) levels of underground parking. We are 9 stories tall out of the ground.

They have great water pressure at the site with 140 static and 118 residual, flowing about 1,900 GPM, but with our floor-to-floor distances, I cannot get 100 PSI at the top of my standpipes. The building footprint is spread out, so I will need (8) standpipes to cover the hose lay inside the building (fully sprinklered). I'm assuming one 1,000 gpm pump will cover all the standpipe demand.

To complicate matters, this is in a seismic area D classification, and with it being a high rise, I am required to have a secondary on-site water supply. The intent was to install an underground tank to supply the fire pump or pumps, if necessary.

My thought was to supply water directly from the city main to the tank, and if there is ever a break in the city supply line, the pump would be served from water in the tank, which would have enough capacity to serve the facility for 30 minutes.

Is 30 minutes the duration I need?

What do you think about how I plan to serve the building? Would that meet the requirement for a secondary water supply?

Do I consider the standpipe demand when sizing the underground tank, or just the most demanding area of my sprinklers?

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I have seen this method of arranging fire suppression components (see attached schematic) several times where I live. The attached is a partial re-creation of the fire water entry schematic for a high-rise building with a fire pump. The system has low and high pressure zones.

The underground parking dry systems are served by the municipal water directly, and the standpipes and aboveground sprinklers are fed by the pump.

Questions: 1. Can you have a FDC serving the low pressure zones as shown on the suction side of the pump per NFPA-14 6.4.3.1?

2. If not, how should the schematic be arranged instead?

3. What could happen if the Low Pressure FDC were pressurized as shown?

​This project was built under the 2013 editions of NFPA-13, 14, and 20. I am asking because I am beginning design of a sprinkler system for a 22 story high-rise. Thanks for your help.

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Is there any requirement for a standpipe to be installed due to travel distance between stairwells in a 3-story R-2 building?

I am reviewing plans of a U-shaped apartment building with two stairwells on the ends. The distance between them is about 470 feet. We are under the 2018 IFC.

If not required by code, would you as the AHJ consider requiring them for improved fire operations?

Thanks for any feedback.

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What is the required pressure for a manual Class III standpipe, 65 or 100 psi?

We're working on a 44'-4" high, 5-story, Type V-B construction building that has a 1-story garage and amenities. The upper floor is R-2. 

The local code says I can have Class III standpipe. As I go through NFPA 13 and NFPA 14, it circles back around to 2-1/2" outlets, except with 2-1/2" x 1-1/2" reducers and caps.

It's going to be fully-sprinklered with a combination standpipe in one stairwell, and just one standpipe riser in the other.

Does this sound correct given the project?

Thanks in advance.

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We're working on a one-story school. The AHJ (Fire Marshal) is requiring inside 2 1/2-inch hose valves at the exit locations.

These hose valves are fed directly off the wet sprinkler system main - not fed from a dedicated standpipe main.

1. I'm having trouble finding code regarding feeding hose valves off of the wet system main.

2. I'm trying to determine if the pipe, off the main, to these hose valves, needs a control valve installed.

Appreciate the tips and insight. 

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Hello everyone. Looking to get some feedback on a building under construction.

I have a 3-story condo building with 4 stairwells, protected by an NFPA 13 sprinkler system. The condo building is exterior access via corridor which connects the stairwells and is about 20 units total.

There is a single fire sprinkler riser that enters one of the stairwells at the corner of the building and goes vertical to serve all levels. Overall, fairly typical.

Currently, the building is nearing the end of construction and they’re installing drywall.

However, a new Fire Inspector is asking for “more standpipes”, despite the fact that the building does not have standpipes, nor are standpipes required (3 stories, none below grade, and below height threshold to the top floor, etc.) The reason he is requiring them is because he is saying per NFPA 14, you cannot exceed ~200 feet in between standpipes. However, because the building does not require standpipes in the first place, this code section does not seem to make sense.

Of course, I know the AHJ is allowed to require things above and beyond the code but my big issue is that the building is about 80% complete now, and he asked for this on a typical inspection. The design criteria, FP shop drawings, civil plan, etc. were all approved by other inspectors/ AHJ / Reviewers, and has been for a couple of years.

I noticed he seems to be intermixing the word “Standpipe” and “Fire Riser” frequently which makes conversations more difficult. Just looking for some other opinions on this issue and I appreciate any input at all.

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Regarding: IFC 905.4 Location of Class I standpipe hose connections.

Class I standpipe hose connections shall be provided in all of the following locations: 1.in every required interior exit stairway, a hose connection shall be provided for each story above and below grade plane,. Hose connections shall be located at the main floor landing unless otherwise approved by the fire code official.

Does this mean a standpipe connection is not needed at the ground floor?

I've brought this up to numerous design/build sprinkler subs and they all say a connection is required at the ground floor.

Thanks in advance.

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I have a standpipe demand of 750gpm. I am providing a fire pump for the system demand.

Should I be selecting a 750 gpm pump or a 1000 gpm pump, based on adding a safety factor (or other reasoning)?

My sprinkler demand is less than 750 gpm so I would only need to provide the 750 gpm for the standpipes. Thanks in advance.

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We have a 3-family building with parking garage and three floors over parking for a total of four floors.

According to the IBC, a standpipe is required; my question is - is the standpipe required in all stairs?

We have two stars which are less than 30-feet between the stairs. 

Thanks in advance.

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A thread to discuss more on Post-Indicator Valve requirements from our blog hits series.

Original 2019 article link: www.meyerfire.com/blog/post-indicator-valve-required-for-my-project

Are you allowed to have a valve off the standpipe feeding a hose valve that is not in the stairwell?

Working in a high rise building with two stairwells. It is dual fed with combination riser standpipes.

On the tenant space there is a hose valve and they want a butterfly on the feed for the hose valve, always thought that was not allowed but couldn’t find it.

Thanks in advance.

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Occasionally, additional hose valve connections are required due to the failure of meeting a 150-ft / 200-ft travel distance to a hose connection.

Can you put a hose valve connection on a sprinkler system without a standpipe?

How do you reflect this in a hydraulic calculation?

A most-remote standpipe would require 500 gpm in a standpipe calculation. Thanks in advance.

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​I am currently evaluating a 7-story building that is being partially renovated and has an existing standpipe system (2 standpipes), but no sprinklers. My scope was to add sprinklers to the renovated areas, creating a partially sprinklered building.

The lack of pressure is leading the AHJ to require a fire pump due the 100 psi required for the standpipe system.

While the standpipe requires the fire pump, hydrant flow tests indicate that there may be sufficient pressure to supply a sprinkler system.

My question is two-fold. Is there really such a thing as a non-combined sprinkler/standpipe system where they are both required?

They both get their water supply from the same source.

Also, can I evaluate supplying the sprinkler system through a separate riser that tees off before the fire pump, while the fire pump supplies only the standpipe, significantly reducing the size of the pump?

The pump would be sized for 750 gpm total, 500 gpm @ 100 psi to the remote hose connections, and 250 gpm to the second standpipe.

What would that sprinkler calculation look like?

Would the sprinkler calculation remove the hose stream allowance and replace it with the 750 gpm to consider the flow to the pump/standpipes?

The flow potential is there based on the hydrant flow test just not the pressure for the standpipes (and it's close for sprinklers). I'm just wondering if I can give the client and rest of the design team options.

Thanks in advance.

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Is it a requirement to have a 42-inch handrail on the edge of the building, due to the standpipe hose connections and this needing to be accessible for the fire department use?

​If it's required, it seems that handrails could apply under IBC 2018 Section 1015.6.

Thanks in advance.

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I'd appreciate some advice.

What's the best way to regulate pressures on a combined sprinkler (OH2) and Class 3 standpipe system?

Obviously the pressures required vary between sprinklers, 2-1/2" standpipe outlets and 1-1/2" hose rack connections.

Pressure regulating valves are expensive to put in on all connections, but I was thinking about using pressure regulating valves for the 2-1/2" standpipe outlets.

I think it's great that we can all share our combined experience on this great website - thanks in advance!

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I'm working with a city inspector who is adamant that we add a second non-rising stem valve (NRS) in the fire sprinkler service main just before the building. The first valve being in the street at the live-tap location with the roadway box.

Is a valve required on the service main before the building?

The requested location would place the valve under the sidewalk, accessible by T-handle wrench only, prohibiting reliable supervision of any kind.

I can't seem to find any language in NFPA 24 that I can use to argue against the second unsupervised valve. I don't see any value in the position the inspector has taken and requested a copy of the city ordinance requiring the additional valve.

Installing the second valve wouldn't be a huge deal but certainly seems like an unnecessary opportunity for an unsupervised valve to get closed or fail. I would like to hear what others in this community think and if anyone has something to offer.

Thanks in advance.

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Has anyone designed a dry manual standpipe for a pier or dock standpipe system in the past?

My question is in regards to materials used for the pipe.

With the tides rising and falling my client is struggling to find an approved material that will allow for enough flexibility.

I walked an adjacent marina to our project and it looked like they used 4" heavy-duty rubber tubing to run out the standpipe lines and transitioned to steel only for the vertical 2 1/2" up to the hose valves on the dock.

Any information to point us in the right direction would be helpful. Thanks in advance.

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