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To what extent are sprinklers required for an above-ceiling mechanical platform in noncombustible construction? See the building section attached. In this case, the platform is nearly the full length of a classroom building. 
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For a single-family home with a 6 in 12 sloped ceiling (roof) that is a combustible wood structure.
Does this need a 1,950 sqft calculation due to the slope, or just two sprinklers as NFPA 13D requires? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Imagine you have a 6-unit, true townhouse-construction building covered by the 2018 IRC under construction. It has an NFPA 13D sprinkler and a one-hour separation between units, but there is one common closet for the sprinkler riser and domestic water main. This closet is accessed only through a door on the exterior and is under the control of the landlord, not the tenant.
What is the code path to require any fire separation between that closet and the dwelling units? There is no dog house off the side. The IRC only seems to call out separation between units, and even if you go into the IBC, it is not apparent. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe How have people been addressing the IFC (2021) Section 907.5.2.1.3.2 requiring 520Hz single/multiple station smoke alarms in residential units being addressed?
It sounds like there are no 520 Hz smoke alarms available on the on the market meet these requirements. We have a roughly 300-unit building and the AHJ is pushing us to put smoke detectors with sounder bases in each unit instead of 120v smoke alarms. We know this could be done, but the cost impacts would be substantial and the future maintenance and inspections in the building would be very difficult. This is the first time we've seen this be pushed by an AHJ, so looking for information on how others have handled this. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We were looking to tie multiple fire alarm systems together from various vendors such as Honeywell, Siemens, Notifier, intermesh, etc. The end goal is to bring all the zone data for a building to a Siemens Desigo Fire Server.
Currently, the Monitoring-Only Solution Assembly (MOSA) ring will not accommodate the Honeywell, Notifier, or other non-Siemens panels to bring in a complete data stream in. We are limited to the standard supervisory signals for trouble, alarm, duct detectors, pull station, and smoke detectors as a limited set of data. Does anyone have an interface that would bring multiple data points from other vendors' fire alarm panels to the Desigo front-end? Siemens and Honeywell do not support each other’s components. The MOSA ring is a Siemens product. A 3rd party would be required to facilitate the interface panel. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe If the system demand is 321.5 gpm for an Ordinary Hazard Group 2 system, do you add the 250 gpm hose allowance before or after calculating the 90-minute supply?
For example, 321.5 gpm + 250 gpm = 571.5 gpm x 90 minutes = 51,435 gallons, or, 321.5 gpm x 90 min + 250 gal = 29,185 gallons. Looking for input to order a water storage tank and the owner is disputing the water storage tank size. We told them we would need a 52,000 gallon tank. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a 5-story building going up with 4-story residential over 1-story parking.
Can the residential portion be NFPA 13R? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Can we connect 2 or three buildings to the same fire alarm system? What about sprinkler?
What code basis (IBC or NFPA 13/72) would allow or disallow multiple buildings on the same system? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe If you have an open office area with (2) AHUs, each AHU supply fan provides 1,500 cfm of supply air and return air that is fully ducted and has no common plenum.
Would duct detectors be provided on the supply side of each AHU? Do you combine the "CFM" since both units serve the same area? If not, would you ever cumulatively add multiple units of CFM? This has been an ongoing question as each of our AHJs sees it differently. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe When retroactively adding a Double Check Valve Assembly (DCVA) to an existing system, we need to verify that the new DCVA does not adversely affect the system's performance.
If no significant adjustments are required, I usually use the hydraulic placard information and compare it to a new hydrant test to determine the system's available pressure. I then subtract the pressure loss from the DCVA at the flow rate indicated on the placard. How do people deal with adding a DCVA to a pipe schedule system with no existing documentation? Thanks in advance! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Suppose on-site water storage for firefighting is required, and an existing tank is on-site sized for the existing building.
Can I add a second tank on site (not connected to the first tank) and just size it for the additional water required for the second building? Ex. A larger building requires a 10,000-gallon tank, while a smaller building requires a 5,000-gallon tank. Can I just install one new 5,000-gallon tank (10,000-5,000 = 5,000 gallons)? Or would the tanks need to be connected so there is no shortage of water? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Is an alarm check valve required in a sprinkler system?
Is there an alternative to an alarm check valve? Are there any restrictions on where the alarm check valve is required to be (i.e., inside or outside of a fire pump room)? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe The hot topic of AFFFs and PFOS. Where is the requirement stating foam must be used for fire protection for a diesel generator inside a building?
We're looking to eliminate the need for foam instead of replacing it with "fluorine" free foam. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I am designing the sprinklers for a building with unusual seismic criteria (it's designed to be seismically resilient and "floats" on seismic isolators).
The structural drawings note that design should be in accordance with ASCE 7-16 equation 13.3-4: Fp = ai ap Wp Ax / (Rp / Ip) I see from NFPA 13 (2022) appendix E that the simplified method is based on ASCE 7-16 equation 13.3-1. Do you think the NFPA 13 simplified bracing method can still be applied/adapted to this alternate equation (without hiring a structural engineer)? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Can a company who is licensed in the installation of fire sprinkler systems perform the acceptance testing of the system or does that company need to be licensed to perform testing and inspections?
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Can ESFR K-Factors be different within the same area, just at different roof elevations? The roof elevations here are dictating different design requirements.  We have multiple ESFR sprinkler systems throughout a new building. The building has two different roof elevations, 38'-4" for the majority of the building, 43'-4" on remainder. We're under NFPA 13-2019 Edition.
The Contractor is wanting to use K-16.8 pendents at 52 psi at the low roof. K-25.2 at 40 psi at the high roof. One sprinkler system will cover the area where the roof steps, with two design areas (high/low roof). The outer thirds of the building separating the roof elevations will have full height concrete tilt-up walls. The center third only has a large open girder truss, with nothing stopping heat from traveling between the low and high roof. Section 7.2.2.6 says ESFR K-factor shall be selected for appropriate hazard. Sections 20.6.2.6 & 23.6.2 indicate ESFR shall be based on building height (amongst other things). Section 23.1.2 for Draft curtains, only reference the adjacent system with standard response sprinklers, not ESFR with different K factors. Section 27.2.4.9.2 says K-factors can't be mixed "for the purpose of minimizing sprinkler over discharge" (consolidated), which is not the case in this scenario. The Roof elevations are dictating the different design requirements. The K-25.2 sprinklers could be used throughout, but the low roof would only require 25 psi and the high roof 40 psi. However, there is a large cost savings going with the K-16.8 sprinkler for the majority of the building, along with additional storage allowance of exposed nonexpanded plastics. My thinking says that there should be some kind of draft stop at the girder truss/roof step to collect the heat, separating the two K-factor/roof elevations, but I am not finding a code reference that dictates it. Any input will help. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe NFPA 20 is pretty clear on the orientation of the eccentric reducer on the suction (upstream) side of a fire pump.
But the diagrams seem to suggest that the diagonal slope (not the flat side) of the eccentric reducer is always on the bottom. Is this true even when the supply is being fed from above? For instance, we often have a stub into a fire pump room from the floor, then a vertical backflow preventer, then the feed comes vertically-down and to the fire pump. Which way is correct for the eccentric reducer when the feed is from above? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have an old existing 3 story building with a basement that is being converted into an apartment building. It used to be a small paint factory.
The architect is calling for a NFPA 13R system, which is understandable since it has all the qualifications for 13R. However, about 90% of the building is exposed 2x12 construction sitting on 10x14 wood beams. The only areas designated to get ceilings are the bathrooms and some kitchen soffits. That leaves most of the building having obstructed combustible construction, which creates a whole series of problems. First, I cannot find any residential sprinklers listed for installation below this type of construction. A smooth, flat or sloped ceiling is required for all of them. The AHJ is using the 2019 version of 13R, and Section 6.2.1.3 allows the use of QR sprinklers in dwelling units, but only if there are no more than four sprinklers in the dwelling unit. All of the dwelling units require more than four sprinklers, so it seems to be that I cannot use 13R at all? Could someone please tell me if I am interpreting and applying these code sections correctly? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Can an elevator hoistway connecting two adjacent stories be considered a "convenience opening" and avoid a fire resistance rating altogether based on NFPA 5000?
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Does a standalone mass notification system (MNS) require a smoke detector in front of the panel for a drug reduction facility?
The facility is 2,100 sqft and houses a minimum of 11 persons. Basically a drug testing and counseling facility. No Fire Alarm required for the building; being governed by UFC 3-600-01 for the US Air Force. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a low-rise building with a manual wet standpipe and a sprinkler system. One combination riser is 6-inch and the other is 4-inch. Standpipes will be Class I.
The calculated sprinkler demand is 195 gpm (Light Hazard). My total manual wet standpipe system demand will be 750 gpm (500 gpm first riser + 250 gpm second riser). Does my fire pump need to accommodate the 750 gpm of the manual standpipe system, since they're interconnected? I know the fire department will handle the standpipe demand, but does the flow rating for the fire pump need to accommodate 750 gpm? I've searched but haven't found specific code references in NFPA 13 or 20 to address this sizing. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Shoutout to another great month of collaboration here on the Forum. Here's our Top Contributors for June:
We have a airplane hangar that is over the 2,000 sqft threshold for a residential hangar, which makes it a Group III Hangar.
I'm having a hard time determining what fire suppression system would be necessary - would it be an NFPA 13 system? It's not really clear in NFPA 409. Thanks for any help. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe When should a red tag be issued for exterior rust on a sprinkler system?
The rust has heavy flaking especially around the weld-o-lets. NFPA 25 leaves a vague interpretation and I just need something a little more concrete to make sure we are covering ourselves. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe |
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