When prescriptive codes reach their ceiling, FM 8-9 Table 17B and engineering analysis open the door — and today’s ESFR sprinklers are ready to walk through it. 

 Warehouses keep getting taller. Driven by rising land costs and the relentless demands of e-commerce logistics, modern distribution facilities routinely push storage heights past 13 meters (43 feet) — and the buildings that house them often exceed 14 meters (45 feet) under the roof deck. For most of the fire protection industry, that height marks a wall. NFPA 13, the dominant prescriptive standard for sprinkler system design in the United States, does not address ceiling-only sprinkler protection above approximately 13.7 meters (45 feet). For designers working under NFPA 13 alone, the answer has traditionally been in-rack sprinklers: additional automatic fire sprinklers installed within the rack structure itself, adding cost and complexity. 

 But there is another path. FM Global’s Property Loss Prevention Data Sheet 8-9 — widely used by insurance and risk engineers worldwide — does address taller buildings through Table 17B. And the mechanism for unlocking Table 17B in a jurisdiction governed by prescriptive codes is Performance-Based Design (PBD). This article explains how that pathway works, why it matters, and what products are available right now to make it real. 

The Prescriptive Ceiling and Why it Exists 

Prescriptive codes like NFPA 13 work because they are clear, consistent, and easy to enforce. A designer follows the rules; an inspector checks the boxes. There is no ambiguity. The trade-off is flexibility. Prescriptive rules are written around the most common scenarios. When a project falls outside of those scenarios — unusual geometry, novel hazards, or extreme building heights — the code either prohibits the approach outright or goes silent. 

 The 13.7-metre (45-foot) ceiling height limit for ESFR-only protection under NFPA 13 is not arbitrary. It reflects the fire test data that existed when those rules were written. Higher ceilings allow fire plumes to develop more energy before an automatic fire sprinkler activates. The concern is that a single tier of ceiling sprinklers may not be able to deliver enough water, fast enough, to suppress a fire in very tall high-piled storage. 

FM 8-9, by contrast, has kept pace with large-scale fire test programs conducted at heights beyond what NFPA 13 currently covers. Table 17B provides approved design criteria for ceiling-only ESFR protection of storage up to 15.2 meters (50 feet) under ceilings up to 16.8 meters (55 feet) — without in-rack sprinklers. That is a significant competitive advantage for any facility that qualifies. 

What Is Performance-Based Design? 

Performance-Based Design is an engineering approach that asks a different question than prescriptive code. Instead of “Does this system comply with the rules?” it asks: “Does this system achieve an equivalent — or superior — level of fire safety compared to what the standard requires?” 

Both NFPA 13 and the International Building Code (IBC) explicitly permit PBD. Section 1.4 of NFPA 13 allows alternatives to prescriptive requirements when a design is supported by engineering analysis and approved by the Authority Having Jurisdiction (AHJ). The IBC similarly includes a provision — often referenced as the “alternative materials and methods” clause — that allows code-compliant alternatives when equivalency can be demonstrated. 

In practice, this means a fire protection engineer can present the AHJ with a documented case that FM 8-9 Table 17B — backed by FM Approvals’ own large-scale fire test program — represents an equivalent or better level of protection than NFPA 13 prescriptive requirements for that specific project. It is not a workaround. It is an engineered alternative, supported by data, and subject to AHJ approval. 

FM 8-9 Table 17B: What it Actually Allows 

FM 8-9 Table 17B establishes design criteria for ceiling-only ESFR protection of Class I–IV commodities and cartoned unexpanded plastics. The key parameters that make it valuable for tall warehouses are: 

• Maximum storage height: 15.2 metres (50 feet) — well beyond the NFPA 13 prescriptive limit. 

• Maximum ceiling height: 16.8 metres (55 feet). 

• No in-rack sprinklers required when ceiling-only K-factor and pressure criteria are met. 

• Approved for both K-28.0 (400 metric) and K-33.6 (480 metric) ESFR sprinklers. 

That last point is critical. The approved products are not theoretical. They are commercially available, listed, and tested today. 

The Products Behind the Performance 

Three manufacturers currently offer FM Approved ESFR pendent automatic fire sprinklers suited for Table 17B applications. All three products meet the FM 8-9 storage protection requirements when installed in accordance with the Data Sheet. 

Reliable Automatic Sprinkler — Models N28T6 and N28T3 (K-28.0 / 400 metric) 

Reliable’s N28T6 (SIN R603) and N28T3 (SIN R604) are FM Approved as Quick Response Storage sprinklers with a K-factor of 28.0 (400 metric). Under FM Data Sheet 8-9, they are approved for storage up to 15.2 metres (50 feet) under ceiling heights up to 16.8 metres (55 feet). Both models use a robust nickel alloy fusible link operating element and a 1″ NPT or ISO7 R-1 thread connection rated to 12 bar (175 psi) maximum working pressure. The N28T3 carries an additional cULus Specific Application Listing for rack storage arrangements permitting a minimum transverse flue space of just 75 mm (3 inches). Reliable has also published an Environmental Product Declaration (EPD) for both models — an increasingly important credential for sustainable construction projects. 

Reliable Automatic Sprinkler — Model M336 (K-33.6 / 480 metric) 

The Reliable M336 (SIN R610) steps up to a K-factor of 33.6 (480 metric), allowing the same level of storage protection at lower design pressures or greater water delivery where hazard levels demand it. It is FM Approved and CE Certified, making it a strong option for projects with international insurance requirements. A notable feature is its connection flexibility: the M336 is available in 1-1/4″ NPT threaded, ISO7 BSPT threaded, and 1-1/4″ grooved (AWWA C606) configurations. The grooved option can simplify installation in large-footprint facilities where grooved pipe systems are already in use. 

Tyco (Johnson Controls) — Model ESFR-34 (K-33.6 / 480 metric) 

The Tyco Model ESFR-34 (SIN TY9286) is a well-established K-33.6 (480 metric) ESFR pendent automatic fire sprinkler with FM Approval and CE Certification. Its technical data sheet explicitly states it can protect a storage arrangement of 15.2 meters (50 feet) under ceiling heights of 16.8 meters (55 feet) without in-rack sprinklers — the hallmark Table 17B application. It uses a 1-1/4″ NPT or ISO 7-R 1 1/4 thread connection rated to 12.1 bar (175 psi). Tyco’s ESFR-34 has a long track record in FM-insured facilities and is supported by established distributor networks globally. 

Viking Corporation — Model VK514 (K-28.0 / 404 metric) 

Viking’s VK514 (SIN VK514) is UL Listed as a Specific Application ESFR Sprinkler and FM Approved as a Quick Response Storage sprinkler, with CE Certification as well. Its FM approval covers two ceiling height scenarios under Table 17B: storage up to 13.5 meters (45 feet) under 15.2-metre (50-foot) ceilings, and storage up to 15.2 meters (50 feet) under 16.8-metre (55-foot) ceilings — each with distinct hydraulic design criteria. The VK514 uses a 1″ NPT or 25 mm BSPT thread and a unique Belleville spring sealing assembly. Viking also offers the VK514 in an InstaSeal-compatible configuration for installations using grooved outlet fittings. 

Making the Case to the AHJ 

A successful PBD submittal for a Table 17B application typically includes the following elements: 

• A clear description of the project: building height, storage height, commodity class, and storage arrangement. 

• Documentation of why the prescriptive path (NFPA 13 with in-rack sprinklers or NFPA 13 ceiling-only limits) does not fit the project. 

• A copy of FM 8-9 Table 17B and the applicable design criteria, showing how the proposed design meets or exceeds those criteria. 

• FM Approvals documentation for the selected automatic fire sprinkler product. 

• Hydraulic calculations demonstrating the system meet the Table 17B design pressure and flow criteria. 

• A written narrative citing the applicable NFPA 13 and IBC provisions that authorize the alternative approach. 

Pre-submittal meetings with the AHJ are strongly recommended. Many AHJs are receptive to well-documented PBD submittals, particularly when the alternative is backed by FM Approvals — a globally recognized third-party testing body. 

The Bigger Picture: Why This Matters for the Industry 

Performance-Based Design is not a loophole. It is an engineering discipline with a documented methodology, peer-reviewed fire test data behind it, and increasing acceptance among AHJs worldwide. When applied to tall warehouse protection, it creates a compelling value proposition: the building owner avoids the cost and operational complexity of in-rack sprinklers. The insurer — typically FM — gets a system designed to their own approved criteria. And the fire protection engineer delivers a solution that is both technically rigorous and commercially competitive. 

The warehouse market is not slowing down. Buildings are getting taller, commodities are getting more complex, and the cost of retrofit sprinkler systems inside rack structures is a real burden on operations. The fire protection industry has the tools — the FM-approved products, the standards framework, and the engineering methodology — to solve this problem today. 

Prescriptive codes will always be the foundation. But when the foundation has a ceiling, Performance-Based Design is the elevator. 

 About IFSA 

The International Fire Suppression Alliance (IFSA) is a global nonprofit organization dedicated to promoting water-based fire protection systems. IFSA supports the development and adoption of active fire protection standards worldwide, advocates for technically sound fire suppression solutions, and serves a membership network of manufacturers, distributors, installers, engineers, and end users across six continents. For more information, visit ifsa.global or contact mfessenden@ifsa.global.