I'm working on a project that is using cold-formed steel joist framing to build a mezzanine in a existing warehouse. They are using 3/4" plywood as the subfloor. They are actually forming the studs on site as they go.

​Is this considered a combustible concealed space?

Would this require COIN (combustible interstitial) sprinklers per NFPA 13 Section 8.15.1.6?

The framed joists are 2-inches deep, and from deck to ceiling is 60 inches.

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From Joe - first - thank you for being a part of this community. This forum really has turned into something outstanding, and far better than I could have hoped for when we brought it to life a few years ago. You may be surprised to know just how popular this is now with over 4,000 daily email subscribers. Keep up the great work, and thanks for being part of it!

Today I'd like to open up a discussion and ask for some feedback on a draft we created for design of Fire Alarm for Elevators.

A lot has changed in this space. I first put this draft version together a year ago, and now with the 2022 Edition of NFPA 72 out (among other code updates). 

Well, now a year later, it's time I kick this into gear and get a formalized version together. Before I wrap this up and get through my own updates, I'd like to extend an invite; if you're a fire alarm junkie and you hear intelligibility whale noises in your nightmares, please take a look and let me know what feedback I might be able to incorporate. 

We're all in this together and we're certainly trying to get things spot-on, so as always I appreciate and welcome the input. Feel free to post below, or if you'd rather just let me know directly, at [email protected].

​Thanks so much for being a part of what we're doing here!

​- Joe Meyer

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I'm new to the estimating space, and I was wondering if there is any good material or training outlets to learn best practices in quoting projects.

I'm on the fire sprinkler side, so I'd be interested in learning as much as I can about labor, labor hours, material quotes, etc. 

Thanks in advance!

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How do you determine the sprinkler temperature when placed within range of a mini-split HVAC unit?

Is there any reason to have sprinkler temperatures different from the "Unit Heater" detail we've known for a very long time?

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We have a military project in the US, so the project is mandated to be compliant with UFC criteria.

We are required to locate an LOC (Local Operating Console) within 200-ft of all portions of a building.

Is exiting the building, and re-entering, to access an LOC permissible? 

If we have exterior-only mechanical rooms, electrical rooms, or maintenance bays (which each only access the outside), then at what point would an LOC be required in each of these spaces?

I'm not trying to be facetious or dramatic, just looking for outside opinion on working through a gray area in my mind.

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We are adding a vertical backflow preventer to my riser assembly.

What minimum dimension do I need for the closet doors to keep it accessible for testing and maintenance?

If there are large doors, can the doors be adjacent to the backlfow and open to provide the access to the backflow?

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We're designing a Wet Manual Class I standpipe in a low-rise building with 4 stairs/standpipes and therefore 4 isolation valves. There are 7 total levels of this building.

The horizontal supply pipe must be located in the level 5 ceiling.

​Is it allowable to locate the standpipe isolation valves at this 5th level versus the more typical location near the bottom of each standpipe?

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NFPA 13 Chapter 19 indicates that for sloped ceilings over 16.7 percent or 9.5 degrees, the system area shall be increased by 30 percent.

My understanding is that the test facility used had this limitation.

We further do recognize that highly sloped ceilings will cause heat to move fast towards the apex and will result in a delayed response of sprinklers, or worse, heads operate over areas not affected by fire.

With a ceiling of 10 degrees which is 0.5 degrees over the limit, will the affect on sprinkler operation really be affected to the extent where the 30% corrective is considered essential?

Without running a full CFD model, the three means of calculating response times of sprinklers we have do not consider ceiling pitch adequately. Looking at calculated results it simply would be more effective to just have lower sprinkler temperature ratings and use quick-response. 

Would use of quick response sprinklers be enough to mitigate the concern in CMSA design instead of high temperature sprinklers (K11.2 or more)?

Thinking a little outside the box here, thanks in advance for the advice/input. 

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Canopies and overhangs have been discussed extensively, including the Meyerfire article and Exterior Projection Cheatsheet.

I know when and how NFPA 13 requires protection, but I am finding architects often provide a "gap" between the face of the building and an exterior canopy. Sometimes this gap is very small.

I have had an AHJ tell me a gap of any size results in no protection required, even if a roof overhang overlaps above.

I'd like to ask the building code experts here if this is a function of if the area beneath is considered part of the Fire Area.

Once again I have a project where it is a wide canopy of combustible construction, would require protection beneath, but it is free-standing, with just a couple inches gap between the canopy and the exterior wall of the building.

Sprinklers required, or not?

Thanks in advance.

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Does NFPA 13 require pipe hangers and supports (that are not UL/FM listed) to account for pressure thrust forces and any other forces beyond NFPA 13-2019 Section 17.1.2 for five times the weight of the water-filled pipe plus 250 lb at each point of piping support?

We have a 6-inch dry standpipe and we calculated a downward force of around 2,000 lbs to satisfy NFPA 13-2019 Section 17.1.2.

However, taking thrust into account at a specific location with a 90 degree elbow, the calculated thrust force is around 6,000 lbs. This appears very high and wondered whether any other fire protection professionals can weigh in on whether thrust force should be accounted for in the calculation.

I do not see any NFPA 13 requirements to satisfy thrust forces for aboveground piping. Thanks in advance.

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Is there a code or standard that specifies floor clearance in front of a fire pump controller cabinet?

I am installing a fire pump in an existing building which has a controller with a transfer switch. Of course the fire pump room size presents clearance issues.

I have clearances I need for sprinkler pipe, but I do not know the working clearances required in front of the cabinets. 

I do have door swing clearance, but was wondering about a working clearance. Thanks in advance.

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Do you know of jurisdictions that require Aboveground Test Certificates for sprinkler system modifications that do not involve hydrostatic testing?

Aboveground Test Certificates are provided for documentation of the modifications, however these include provisions for hydrostatic testing. Am I missing something here?

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I have a question that I have been pondering for a while. As an AHJ we have some strip malls (or similar construction where there are multiple businesses in different suites), and in a few instances I have come across a single suite that is sprinklered due to the occupancy type within that suite.

For example an older strip mall gets a casino to move into a single suite changing it to a Group A occupancy, which now requires sprinklers. They have been allowed to sprinkler just that suite as long as there is a 2-3 hour rated fire separation between the neighboring suites.

Is this in alignment with the code?

Are they considered “separate buildings” due to the fire separation provided between suites?

If so, how do we avoid confusion when our crews respond for a fire?

They see a PIV and FDC and connect, only to realize when they go inside that there aren’t even sprinklers in the suite on fire. It just doesn’t seem operationally sound to me. Do you have any thoughts on this?

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We have a 6-inch Schedule 10 main being hung with a trapeze hanger. The span on the hanger is 6-ft. 

We're using a 2-1/2 inch Schedule 40 pipe as the trapeze.

Does the 2-1/2 inch hanger rings and rods with beam clamps need to use 1/2-inch diameter rod, since it is supporting 6-inch pipe, or can it use 3/8-inch hanger rings and rods? 

NFPA 13 2016 Section 9.1.1.7.5 states "all components of each hanger assembly that attach to a trapeze member shall conform to 9.1.1.5 and be sized to support the suspended sprinkler pipe." Table 9.1.2.1 shows pipe sizes up to 4-inch require a minimum 3/8-inch rod and 6-inch requires a  minimum of 1/2-inch rod. 

Thanks in advance.

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When using loop hangers in fire sprinkler systems, is there a distance (minimum or maximum) that the end of the all-thread rod needs to be from the top of the steel pipe?

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I have a job where the plans have a detail of the underground fire service entry into the building that shows us bolting to friction clamps. I've always used the 90-degree I bolts on the flange to shields.

Looking for some detail on this - are there other methods I should be considering? Is this acceptable?

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When is sprinkler protection required for a building column?

We have a New York City project with cast iron columns, and we're not sure of any code requirement that would address sprinkler requirements for protection of a cast iron column.

Any help is much appreciated.

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According to the International Building Code Section 905.3 (2018 Edition), a standpipe is required in any building with four or more stories.

We have a small building (three family homes) but the first floor is all a parking garage, and then 3 more floors over the parking garage (one home per floor).

According to the IBC, do we still need a standpipe even if it's such a small building?

If we do need a standpipe, does the service have to be 4-inches or can we have it at 2-inches and increase the riser up to 4-inches to feed the manual wet standpipe?

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Why does NFPA 13 limit the use of ESFR sprinklers in storage occupancies to 46 feet (14 meters)?

Looking for some next-level insight here.

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I have a surface-mounted light fixture on the ceiling, and I have to have a sprinkler at least 12-inches away from it in order to clear it as an obstruction. The light fixture is rectangular in shape.

The question is, when doing all of the spacing and the sprinklers are not exactly next to the object, they will have an offset from one side, and another offset from the other (short) side of the light fixture.

Does the sprinkler distance from the object need to be measured diagonally?

Or is the measurement "aligned" with one (or all) sides of the light fixture?

I may be overthinking this, and hopefully am explaining it correctly. Just because I'm 1-foot from the long side I could still be 6 or 8-inches offset from the other side of the fixture. Any help is much appreciated.

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​Thanks to everyone for another great month here on the Forum! Here's our top contributors from May 2022:

Our project is a 16-bed hospice facility. The project site does not have a municipal water supply. The project is under NFPA 13, mostly Light Hazard, and an ancillary storage space in the basement is Ordinary Hazard.

We've designed a water storage tank which is buried outside. The discharge of the tank is approximately 5-feet above the suction side of a fire pump supplying the sprinkler system.

I've designated the pump as a sprinkler booster pump and supplied power from an emergency MDP (main disconnect panel). The electrician is asking for a few details concerning the pump designation.

Is the fire pump required to have a separate service with a dedicated ATS (automatic transfer switch)?

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