Use Fire-Rated Construction in lieu of Sprinklers?

10/31/2024

Is fire-rated construction ever enough to not warrant sprinkler protection?

Is there a NFPA 13 section that would validate this one way or another?

Thanks in advance.

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

14 Comments

Brett

10/31/2024 06:28:40 am

Typically, no, but this is too vague of a question to give a straight answer to. The answer to your question will be found in your relevant building and or fire code.

NFPA 13 tells you how to design and install sprinkler systems. It does not tell you when a sprinkler system is required.

Jen McHale

10/31/2024 08:18:41 am

There is but only for electrical equipment rooms and there are specific criteria that need to be met (2 hour rated enclosure, no storage, dry electrical equipment only, etc). 2019 edition NFPA 13 9.2.6

franck

10/31/2024 08:22:51 am

And this is only as some regulations prohibit the presence of water pipes over electrical cabinets (at least at a certain distance)

franck

10/31/2024 08:21:07 am

It is definitely not in nfpa 13 as it is for the design of sprinkler systems, not for not the need of sprinklers

Answer may come from the Insurance company that may accept or not having no sprinkler protection.

But non combustible constructions is not the same purpose than sprinklers.
One is passive protection and the other is active protection
A non combustible construction does not prevent that everything can burn inside the building

This means that a combustible construction with nothing to burn inside requires sprinklers (to protect the building) and a non combustible construction may require sprinklers as well to protect the inside.

Glenn Berger

10/31/2024 08:21:51 am

Per the IBC, you can potentially avoid sprinklers with a more robust construction type. But this is based upon occupancy and other building parameters.

NFPA 13 provides details for the design, installation, testing and maintenance of sprinkler systems. It is very limited on where sprinklers may be omitted in an otherwise fully sprinklered building.

Adam

10/31/2024 08:22:09 am

I have been involved in projects in small towns where the water supply is inadequate to support a sprinkler system, but the Code may require one. This has either stopped projects entirely, or created conflicts between building owners and the AHJ.

I am aware of one instance in my area where an Architect has provided a robust fire-rated assembly in lieu of a sprinkler system, but this is a great risk. I know from speaking to the Architect that they were not at all comfortable providing that Alternative Solution.

A fire-rated assembly supposedly contains a fire to a set space for a minimum amount of time, but without intervention, it can be assumed that the entire space would be destroyed by the fire, and people could be trapped within. With a sprinkler system, there is a good chance that the fire will be extinguished, or at least controlled, in order to allow for people to leave the space, and maybe prevent complete loss of the space.

In my opinion, no amount of fire-rating is equivalent to a fully-functioning sprinkler system.

Greg

10/31/2024 09:41:09 am

Adam's post is similar to my thoughts and experience regarding rural locations. Alternates for sprinkler coverage seems to occur in Ag-related seed process and manufacturing, where building separation is used as a key provision for loss-control. Fire wall separations in low-hazard storage warehouses, Type II construction and in a few instances, the construction type of dryer-buildings is inherently fire resistive, Type I.

For some companies who operate in the Ag-seeds business, the installation smoke detection systems is cost-effective and used for improving life-safety and initial response from rural fire departments.

In nearly all cases where sprinkler decisions arise, the predominant factor is the availability of a meaningful underground water supply from the local water utility, and/or the distance to connect to water line service.

J.H.

10/31/2024 08:40:31 am

The answer is not in NFPA 13, and will depend on the local adopted Codes.
If NFPA 1 is adopted, you will find sprinkler requirements in NFPA 1, Chapter 13, Section 3.2, "Where Required".

Jay

10/31/2024 09:40:43 am

If you compartmentalize a building sufficiently into separate fire areas that are each less than that which requires a sprinkler system to be installed per the occupancy in the IFC, IBC, NFPA 1, then yes. Of course there are those occupancies that require a fire sprinkler system regardless of fire area such as residential.

Charles Riforgiate

10/31/2024 09:44:36 am

2018 IBC Section 901.7 Fire Areas
Where buildings, or portions thereof, are divided into fire areas so as not to exceed the limits established for requiring a fire protection system in accordance with this chapter, such fire areas shall be separated by fire walls constructed in accordance with section 706.

Fire wall construction is permitted to reduce the fire area of a building or structure beneath the fire sprinkler thresholds indicated in sections 903.2 through 903.2.12.

i.e. - Group F-1 requires fire sprinklers where the fire area exceeds 12,000 s.f. (proposed F-1 13,000 s.f. building)
Use fire wall construction to create "separate buildings" resulting in 2 fire areas - #1-9,000 s.f. - #2 - 4,000 s.f.

Mark Harris

10/31/2024 01:57:00 pm

All great comments. In smaller towns in IL I have seen 2 or 3 less than 12,000 SF metal buildings built with some separation and a corridor between buildings with rollup fire door at corridor entrance. Only reason I can imagine for that was to avoid fire sprinklers. And as noted above probably inadequate water supply.

Todd E Wyatt

10/31/2024 09:56:18 pm

SUMMARY
ASPS are not permitted to substitute for the minimum FRR of building elements, components or assemblies UNLESS an “alternative design” is submitted to the AHJ and they approve it (per IBC-2021 104.11).

EXPLANATION
The scoping Code (e.g. IBC-2021) identifies WHERE an automatic sprinkler system (ASPS) is required based on the Occupancy Classification(s) (OC) assigned to the building (Group R-2) and/or “Specific Building Areas and Hazards”, not the Type of Construction (TC) of the building.

The referenced ASPS standard (e.g. NFPA 13-2019 or NFPA 13R-2019) prescribes HOW a building’s/structure’s ASPS is to be designed, installed, inspected, and maintained.

The IBC-2021 includes “EXEMPT LOCATIONS” per 903.3.1.1.1 (7 exemptions) & 903.3.1.1.2 (1 exemption) … see REFERENCES below.

There are (3) methods for determining the fire-resistance rating (FRR) of building elements (including FRR for primary structure (e.g. columns)), components or assemblies:

1. 703.2.1 Tested Assemblies
2. 703.2.2 Analytical Methods
3. 703.2.3 Approved Alternate Method

Based on the 703.2, the “703.2.2 Analytical Methods” is to be used “WITHOUT the use of automatic sprinklers or any other fire suppression system being incorporated” so this option is out.

That leaves “703.2.1 Tested Assemblies” or “703.2.3 Approved Alternate Method”.

If the life safety engineer can provide a tested assembly that includes an automatic sprinkler system (ASPS) meeting the requirements of the required FRR assembly for the column, the AHJ may permit it.

However, many AHJs will NOT approve the substitution of a required passive FRR assembly (e.g. encasement, FRR membrane protection of a wall, or SFRM) with an “active system” such as an ASPS. ASPS are not always 100% effective and some AHJs may use the intent of “WITHOUT the use of automatic sprinklers or any other fire suppression system being incorporated” per “703.2.2 Analytical Methods” against the requirements of “703.2.1 Tested Assemblies.”

“Water curtains” are permitted to be substituted for fire-resistance rated (FRR) opening protectives in buildings protected throughout by an automated sprinkler system (ASPS) by the scoping Code (e.g. IBC-2021 705.8.2) if approved by the AHJ (e.g. Building Official).

Opening Protectives (OP) are (typically) required based on the Fire Separation Distance (FSD) between the Exterior Walls (EW) and adjacent building(s) and/or the property line(s). Other than the exception for Opening Protectives per 705.8.2, the 1-Hr Fire Barrier (1FB) protection of atrium (window) walls can be downgraded to a 1-Hr Smoke Barrier (1SB) if IBC-2021 404.6 (3) Exceptions are met. ASPS providers have tried to use this atrium ASPS exception as a substitution for other FRR assemblies. Only the AHJ can approve of these “alternative designs.”

REFERENCES
Chapter 9 Fire Protection and Life Safety Systems
Section 903 Automatic Sprinkler Systems
903.3 Installation Requirements
903.3.1 Standards
903.3.1.1 NFPA 13 Sprinkler Systems
Where the provisions of this code require that a building or portion thereof be equipped throughout with an automatic sprinkler system in accordance with this section, sprinklers shall be installed throughout in accordance with NFPA 13 except as provided in Sections 903.3.1.1.1 and 903.3.1.1.2.
903.3.1.1.1 Exempt Locations
1. Automatic sprinklers shall not be required in the following rooms or areas where such rooms or areas are protected with an approved automatic fire detection system in accordance with Section 907.2 that will respond to visible or invisible particles of combustion. Sprinklers shall not be omitted from a room merely because it is damp, of fire-resistance-rated construction or contains electrical equipment.
2. A room where the application of water, or flame and water, constitutes a serious life or fire hazard.
3. A room or space where sprinklers are considered undesirable because of the nature of the contents, where approved by the fire code official.
4. Generator and transformer rooms separated from the remainder of the building by walls and floor/ceiling or roof/ceiling assemblies having a fire-resistance rating of not less than 2 hours.
5. Rooms or areas that are of noncombustible construction with wholly noncombustible contents.
6. Fire service access elevator machine rooms and machinery spaces.
7. Machine rooms, machinery spaces, control rooms and control spaces associated with occupant evacuation elevators designed in accordance with Section 3008.
903.3.1.1.2 Bathrooms
In Group R occupancies sprinklers shall not be required in bathrooms that do not exceed 55 square feet (5 m2) in area and are located within individual dwelling units or sleeping units, provided that walls and ceilings, including the walls and ceilings behind a shower enclosure or tub, are of noncom

Todd E Wyatt

10/31/2024 09:57:04 pm

903.3.1.1.2 Bathrooms
In Group R occupancies sprinklers shall not be required in bathrooms that do not exceed 55 square feet (5 m2) in area and are located within individual dwelling units or sleeping units, provided that walls and ceilings, including the walls and ceilings behind a shower enclosure or tub, are of noncombustible or limited-combustible materials with a 15-minute thermal barrier rating.

Todd E Wyatt

10/31/2024 09:58:17 pm

ASPS = automatic sprinkler system

Use Fire-Rated Construction in lieu of Sprinklers?

Leave a Reply.

ALL-ACCESS

SUBSCRIBE

COMMUNITY

YOUR POST

PE EXAM

FILTERS

ARCHIVES

PE PREP SERIES