I have a fire wall on a two-story building providing separation for purposes of having two control areas.

There is a small roll-up door on the 2nd floor (in the main egress corridor of the building) in the firewall that can be opened to bring up items from the 1st floor to the 2nd through a lift from the 1st floor.

Is it code compliant to only have smoke detectors in the immediate area of the roll-up door (on each side) trigger the fire pin that closes the door, or, does every single smoke detector (it's a large building) need to trigger the roll-up (fire) door to close?

I am not finding a concrete code section (IBC or NFPA) that all detectors need to trigger the roll-up door to close.

Again, it's a very large building with many detectors. Thanks in advance for any answers/feedback.

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NFPA 13 2016 Section 8.15.12 outlines requirements for Concealed Spaces Not Requiring Sprinkler Protection.

I am building a Type V-A (wood-framed) apartment complex.

Are sprinklers required in wood-framed drop ceilings (soffits), below exterior cantilever walkways?

Walkway construction is wood-framed, with insulation in the cavity, 5/8-inch gypsum below, and 2-1/4 inch hard rock concrete on crickets. The referenced assembly is GA FC 5420.

This space will have soffit vents along the entire length. The depth varies from 6-inches to 12-inches.

This project is under NFPA 13, thanks in advance.

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We have a hotel that is constructed with 12-inch TJI joists (composite engineered wood joists which have a continuous web, not an open web). There are gypsum ceilings attached directly to the bottom of the TJI joists. There is also at least 3.5-inches of insulation above the gypsum ceilings.

Are we required to calculate 3,000 sqft or 8 residential sprinklers, or do we meet the noted code exception below?

NFPA 13-2019 19.3.3.1.5.2(4) Item (10): Light or ordinary hazard occupancies where noncombustible or limited-combustible ceilings are attached to the bottom of composite wood joists either directly... , provided the adjacent joist channels are firestopped into volumes not exceeding 160 cubic ft, using materials equivalent to 1/2-inch gypsum board, and at least 3-1/2 inches of batt insulation is installed at the bottom of the joist channels when the ceiling is attached utilizing metal channels.

What are the "adjacent joist channels"?

And does the construction we have equal the firestopping as noted?

Does the gypsum ceiling attached to the bottom equal the firestopping, or is the firestopping something additional?

Roland Huggins wrote a good article on this issue, but I'm still not sure.
https://sprinklerage.com/sprinkler-protection-3000-ft2-modifier/

I have another senior tech convinced that this section is referring to an "unprotected" or non-firestopped combustible concealed space.

Thanks in advance.

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I have a flat exterior canopy that projects 10-feet from the building, constructed of 2x solid wood joists, ceiling attached directly to the underside, roof sheathing directly to the top.

There is no storage beneath the canopy; the area below would be considered light hazard.

I am having the architect change the sheathing attached directly to the underside from plywood to cement board, so I think I will meet the criteria to allow sprinklers to be omitted from beneath, per NFPA 13 Section 8.15.7.3 (2016 Edition), or Section 9.2.3.3 (2019 Edition), confirmed by the MeyerFire Canopy, Overhang, & Exterior Projection decision tree cheat sheet. (I realize I might have to take a closer look at the exposed material of the roofing.)

NFPA treats the area below, and the concealed space within the canopy separately. There are the combustible concealed space exceptions.

In my canopy, does the 4-foot width limit of 8.15.1.2.1.2 (2016), 9.2.1.19.2 (2019) mean I have to sprinkler the joists channels, or does the combustible concealed space omission of 8.15.1.2.5 (2016), 9.2.1.5(2019) overrule?

NFPA 13 9.2.1.5 (2019): Concealed spaces formed by ceilings attached directly to or within 6-inches of ... solid member construction shall not require sprinkler protection.

NFPA 13 9.2.1.19.1: Sprinklers shall be permitted to be omitted from within combustible... overhangs... that are constructed in accordance with 9.2.1.19.2 through 9.2.1.19.5.
NFPA 13 9.2.1.19.2 (2019): Combustible soffits, eaves, overhangs... shall not exceed 4-feet in width.

I’m thinking the section for sprinklering within canopies is more applicable to canopies with a larger void space within, that may not meet the usual combustible concealed space exceptions, where you’d have to make some minor modifications, no openings, and add draft-stopping to omit sprinklers from within the space.

The architect said on a canopy similar to this one, they had to fill the 2x joists channels with insulation, but I don’t where code would direct us to do this, unless they were TJI’s.

Does the 4-foot width limit specific to Exterior Soffits, Eaves & Overhangs overrule the Concealed Space Rules?

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NFPA 13, Section 8.15.8.1.1 exempts sprinkler coverage in bathrooms that do not exceed 55 square feet and have walls and ceilings of noncombustible or limited-combustible materials with a 15-minute thermal barrier rating, to include the walls and ceiling behind the tub/shower.

My question is - would a plastic shower assembly that has been tested in accordance with ASTM E162 and is classified as a Class II or Class B material be capable of providing the 15-minute thermal barrier alone?

Or, would a separate material still be needed behind the tub/shower assembly?

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I was asked to evaluate a warehouse that was built in 1996 for a new racking permit.

The original fire sprinkler system was designed with ESFR sprinklers with a K factor of 14.0. During the evaluation I found that the building peak was 40'-0" tall. Knowing that NFPA 13 no longer allows K-14 ESFR sprinklers in a building over 32'-0", I informed the building owner that the existing sprinklers need to be replaced with a larger-orifice ESFR sprinkler.

The building tenant has tried everything they can to find away around this and does not understand why the building is not grandfathered.

I am just curious if anyone else has encountered this situation and what the outcome was.

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I have a project for a Cast and Forging plant, which requires a "double interlock sprinkler system per NFPA 13". That's the first I've heard of a "double interlock sprinkler system".

My question is do I have to use a deluge valve or would this be an alarm check valve?

​Would nozzles be open or closed?

Many questions, thanks.

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A project I'm on has a lobby area with a 35-foot tall ceiling next to the elevator door. 

NFPA 72-2010/2013 Section 17.7.3.1.3 and 17.7.3.1.4 allows a smoke detector within 60-inches of the top of each elevator door to protect the opening. This can be used for elevator recall.

In addition to this smoke detector, do I also need one at the ceiling (35-feet) for normal coverage?

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To me, it makes more sense to locate a backflow on the suction side of a pump. However, I have recently run across a facility with the backflow downstream of the pump (discharge side).

The main fire pump controller is connected between the the first check valve and the backflow preventer.

The jockey pump is connected after the backflow preventer.

Here's the problem: when the first check valve fails, the main fire pump continuously starts & stops because the pressure is bleeding off they the relief valve while the jockey pump remains idle.

Is this an acceptable scenario?

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Distilled alcohol storage on single/double row racks. I feel like I am loosing my mind in a big way.

I currently have a larger liquor store that I am trying to design that will have a stock room which will utilize 10-ft tall single and double row racks. These racks can contain alcoholic beverages that exceed 20% (Everclear).

What standard/section does this fall under?

So far I've only found sections that exclude this kind of commodity. I am sure I'm missing something stupid simple on this one. Thanks ahead for the help.

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I am reviewing a building under construction for a client, specifically the wet sprinkler system installation.

There was a problem where the installer left caps off the pipe both on pipe being stored and pipe installed at the ceiling. My client stated concerns about debris falling into the pipe due to other trades doing work in the area and requested that the sprinkler installer perform corrective measures, they proposed using compressed air to blow out the pipe.

The client wants them to provide some type of justification, industry standard or NFPA guidance that says this is an acceptable means.

I looked in NFPA 13 and NFPA 25 and only found how to deal with in-service systems that have obstructions.

Has anyone dealt with a similar situation or know what the industry standards are for cleaning out pipe during the construction phase?

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I was hoping to get some feedback on whether interior Special Application Window Sprinklers would require a separate zone from the remainder of the floor fire sprinkler system?

I do not see any provisions that would require separate zoning per NFPA 13 nor the IBC. However, I can see why it would be important to zone these areas separately seeing as the intent of the window sprinklers is to maintain the integrity of the fire rated separation (as opposed to actively suppressing the fire).

Thanks in advance!

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We have a floor control valve and 2-inch drain pipe on a multi-story building.

Where should I drain this?

If I drain directly to a floor drain in a toilet room, I'm not confident that the floor drain can accept the flow. 

Can I connect it to an HDPE pipe and drain it underground to a gully trap? 

I fear connecting it to anything under tile as the drain lines are PVC and may not afford the pressure.

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Are wet sprinklers required in a woodworking dust collection system with a spark detection and arrest?

Are there any limitations or hazards to installing wet heads in this system such as heads struck by small debris?

Do dust collection system fall under industrial exhaust?

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We design fire protection systems for large industrial plants with a large area network running in the kilometers.

In such case there could be chances of surge due do sudden closure of a deluge valve, check valve, or fire pump. We do not have time/expertise to carry on surge analysis on software.

I have heard about using tanks for surge.

How would we go about sizing an anti-surge tank?

Is there any basic guidelines based on fire water flow rate/pump discharge pressure to get first cut sizing of a surge  protection tank?

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I'm reviewing a apartment building that meets the requirements for an NFPA 13R system.

My questions: A pump is going to be required for this project and they are proposing to use a booster pump on the incoming waterline at the property line to reach the required pressure for domestic and fire demands.

Is a combined domestic/fire pump like this allowed?

It would be a private pump.

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I am building mid-rise wood framed multi-family buildings and am looking into some of the concealed space options available in NFPA 13.

8.15.1.2.17 permits the omission of sprinklers in the concealed space between the underside of wood joists and top of a limited combustible suspended ceiling as long as the joist space is filled with noncombustible insulation within 2 inches of subfloor above.

It is 8.15.1.2.17.1 that I am looking for insight on. It requires that the exposed bottom chord of the joists that would be exposed to the concealed space is faced with a noncombustible product installed as per manufacturers specifications.

Is there a product that has been recognized to satisfy this requirement?

I was thinking about overlaying the fiberglass insulation used to fill the joist cavities to cover the bottom of joist. While it would be full depth in the 2x6 joist, I would compress it and mechanically fasten it so that the joists would not be exposed to the concealed space below.

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I'm reviewing a single-family home NFPA 13D system.

What is the proper way to calculate a 13D system? Is this a 2- or 4-sprinkler calculation?

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I am looking at a project that shows 6-inch underground lead-in to a riser room. The specs however call out the install of a 1,000 gpm pump. NFPA 20 shows that for a 1,000 gpm pump suction sizing should be no less than 8-inch diameter.

Is a 6-inch even allowed for this application?

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What is the proper hazard classification for an enclosed loading dock?

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We have a water storage tank and a diesel fire pump on our project.

Is there any requirement for the pressure relief valve discharge pipe, when connected to a supply tank, to be extended below the lowest possible water level?

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We are working on a project where the site engineer is asking if tapping into the underground fire line is acceptable to supply a water cooling line to a water source heat pump unit with a 3-inch line.

I'm having trouble finding where it is not acceptable and thought I'd reach out to the knowledgeable members here.

This site has a combination potable/fire line as shown in the picture below.

Should we require them to tie into the 8-inch tap from the potable water line upstream of the fire protection vault (blue line in the drawing)?

Or is it OK that they tap into the fire supply line downstream of the fire protection vault (red line below)?

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