Is an access panel or access door required for sprinklers that are installed in a concealed space?

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

For Fire Pump rooms located in a basement, that is accessed through a common corridor, is it acceptable to have other rooms (like plantrooms, storage, etc) off the same corridor coming from the staircase to the Fire Pump Room door?

We would provide the required fire resistance rating for the stair, the corridor, and the fire pump room. I'm assuming no storage would be allowed within the corridor itself.

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

Already made alternative arrangements for the immediate install, but it can't hurt to ask for the future if this ever comes up again:

Is there any listed upright K8.0 extended coverage sprinkler that is listed for light hazard and combustible construction?

Couldn't find any with Reliable, Tyco, or Viking; but if an alternate manufacturer makes one, it'd be nice to remember for the future.

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

We have a residential project where we are looking to use a residential sidewall sprinklers. The project is under NFPA 13 - 2016 Edition

On a wall where we have a sprinkler, there is a a projecting 3-inch x 24-inch wide x full-height obstruction bump-out of the wall. 

How far away from this would the sprinkler need to be? 

Or, do I need to add a sprinkler on the other side of the obstruction?

I'm wondering if these could be considered "shadow areas" because the shadow area would be under 3 sqft (NFPA 13-2016 8.10.7.1.4, and A.8.1.1(3)).

Thanks in advance.

​​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

I purchased a house with fire sprinkler system that is 30 years old. The previous owner had the sprinkler disconnected about 10 years ago when a furnace repairman stepped on one of the sprinkler pipes. The damage was repaired but the water line to the sprinkler system was not reconnected (not sure why).

I was wondering if it would be okay to have it reconnected now?

It is a 30-year old system and has been inactive for 10 years.

Do the pipes become brittle are there other concerns in reconnecting?

Thanks for you help.

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

A firestop question from someone who doesn't venture much into that space - if we are using a firestop sealant around through-wall pipe and duct penetrations, and there is exposed structure in the room where everything is being painted black, can the sealant also be painted black?

The concern would be possibly compromising the sealant itself, or making future inspections more difficult.

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

I ran into a wet pipe fire sprinkler system that has a small pressure pump installed on the riser.

The control valve and the alarm valve are dated 1957.

Since this pump was installed and accepted, can it be removed or taken out if it's not working?

I understand the pump was used to keep the alarm valve from opening during water pressure fluctuations to keep the false alarms from happening.

​​​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

How should I properly be sizing a vertical branch line that feeds only a five-story trash chute?

Would a hydraulic calculation be a line calculation, so I would calculate as many as five sprinklers?

I typically feed sprinklers from the adjacent floor level, so I've never ran a separate calculation just for a trash chute. My gut says a 1-inch threaded line isn't enough for a trash chute, but I'm not 100% positive how a hydraulic calculation should be done here.

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

Do you specify single phase or 3-phase power for dry system air compressors?

If 3-phase, what horsepower?

I've always gone with single phase but I had a sprinkler contractor tell me recently that they prefer 3-phase compressors because they fill the system better and last longer. I was curious what others would recommend as better practice.

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

So the issue of "forward-flow testing" of the backflow preventers has come up a lot as of late, at least here in Massachusetts. More and more design drawings are calling for "provisions" to forward-flow test the backflow preventer. I've seen multiple ways of doing this and I'm curious as to which method is best.

One method I see is adding a bypass around the FDC check with a normally-closed butterfly valve in it. This allows you to open the butterfly valve when you want to test the backflow preventer and flush through the FDC piping.

The other method I see is to extend the manifold and install a couple hose valves to use in testing.

My personal opinion is that if you have the ability to run the hoses outside, use the second method. The reason for this is that if each zone has a control valve, you can shut off the sprinkler system while flushing and not introduce any of the debris in the underground into your system. By doing it the other way with the bypass, you have to mess with the FDC, and if the FDC is fed from anywhere on the system other than the end of the manifold, you can introduce debris into your system.

Is this a better approach?

​​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

Is there any reason in code (NFPA 13 or 20) that you cannot tie a Fire Department Connection (FDC) line to a pump bypass line as long as the FDC line is downstream of all control valves on the pump bypass?

​​​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

We're doing a full remodel on an existing, vacant, 3-story building.

During the remodel, there won't be any heat in the building. There is an existing fire sprinkler system that would freeze during the winter.

How should we proceed during the remodel? 

Are we required to keep the sprinkler system active? Is the owner required to provide heat? What would you recommend from experience?

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

We have a project that has Class III liquids in Non-metallic IBC (Intermediate Bulk Containers).

NFPA 30 Tables 16.5.2.9 and 16.5.2.10 list storage requirements for Class III liquids in Nonmetallic IBCs. Stacked IBCs are limited to two-high (~8 feet), and in racks, only single and double row racks are allowed.

Under Section 12.8, these containers may be protected as "high storage of Class IV commodities" through NFPA 13, provided that the volume is limited to 13,750 gal (Class IIIB).

Does this mean that under NFPA 13, IBCs can be stacked up to 40-feet with 45-feet ceilings as per Table 23.3.1, or in multiple-row racks up to 40-feet high with 45-feet ceilings as per Table 23.5.1?

Or similar configurations as per Chapter 22 (CMSA)?

Provided the volume limit is not exceeded, of course.

​​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

In my area many designers use the main test/drain or one of the FDC inlets to conduct forward flow for the double check backflow assembly. They use the velocity pressure pitot equation to demonstrate that they will achieve the system demand flow. During the acceptance testing, I verify that the system demand is achieved by measuring with a pitot gauge and calculating the flow.

I generally use a coefficient of 1 when a hose monster or the main drain piping is flowed from, because they are long runs of smooth continuous pipe.

Is this appropriate or should I be using some other coefficient?

​​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

Looking at installing a cable tray that runs the length of the room in an Ordinary Hazard Occupancy.

The cable tray is about 2-feet wide and the sprinklers are standard uprights. The cable tray is less than 18-inches below the sprinkler.

However, the cable tray may be centered directly below some sprinklers, but off to the side for other sprinklers.

What obstruction criteria from NFPA 13 (2016 Edition) would apply?

Three Times Rule (Section 8.6.5.2.1.3)?

If Three Time Rule applies, is that measured vertically, horizontally, diagonally, or all?

Thanks in advance.

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

I'm designing a sprinkler system that uses 1-1/2" diameter pipes working their way through a roof structure.

Once I got the branches run, it occurred to me that they could be sufficient to provide water to the system on their own. I looped the ends together, ran hydraulic calculations, and that theory checked out.

The issue is - how am I to seismic brace this pipe?

I have the pipe "restrained" as branch lines, but there is no main that they tie into. Even if I had a main, these branch pipes take so many turns that functionally it would act isolated from the bracing on the main.

How best should I approach this situation?

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

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.

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

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.

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

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.

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

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?

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

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?

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

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.

​​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

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.

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

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?

​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

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?

​​​​​​​​​​​​​​​​​​​​​​​Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe