Storage and Commodities

High-piled storage fire protection is the set of fire code and sprinkler rules that apply once combustible goods are stored more than 12 ft high, or, where the fire code official requires it, more than 6 ft high for high-hazard commodities such as Group A plastics, rubber tires and some flammable liquids. Two documents do the work: Chapter 32 of the International Fire Code (IFC), which decides when a permit and a high-piled storage plan are required and what the building must have, and NFPA 13, the National Fire Protection Association (NFPA) sprinkler standard, which sets how the sprinkler system is designed for the commodity, the storage height and the storage arrangement. In Maryland and Delaware the fire code side comes from NFPA 1 Chapter 34 instead of IFC Chapter 32, and NFPA 1 counts Group A plastics as high-piled above 5 ft.

This guide is for warehouse owners, developers, industrial tenants, architects and brokers in New York, New Jersey, Pennsylvania, Maryland and Delaware who need to understand what drives the cost and the schedule of a storage building before they sign a lease, buy a building or file for a permit. It explains the mental model, lists every question the Storage and Commodities hub answers, and gives the adopted code editions by state as of October 2026. Each question gets its own article; this page sends the reader to the right one.

What Decides Warehouse Fire Protection: Commodity, Height and Arrangement

Three facts about the stored goods decide almost everything about warehouse fire protection: what the goods are made of, how high they are stacked, and how they are arranged. The code and the sprinkler standard both start from these three inputs. A change to any one of them can change the permit, the sprinkler design and the water supply.

Commodity classification sorts goods into Class I through Class IV, then Group A, B and C plastics, based on how much heat the product and its packaging release in a fire. Cartoned canned food is Class I or II; wood furniture is Class III; a pallet of cartoned plastic housewares is Class IV or Group A depending on the plastic content. NFPA 13 (2022) Chapter 20 holds the classification rules, and IFC Chapter 32 uses the same classes to decide what the building needs. The Definition article on commodity classification, linked in the questions table above, explains the classes and why Group A plastics change the design.

Storage height matters twice. The fire code uses 12 ft (Class I to IV) and, where the fire code official requires it, 6 ft (high-hazard commodities) as the line where Chapter 32 starts to apply, under the high-piled storage definitions in IFC Section 202 and the scope in Section 3201.1. NFPA 1 (2024) sets the Group A plastics line lower, at 5 ft.

NFPA 13 then uses storage height and ceiling height together to pick the sprinkler design: a system that protects Class III goods at 20 ft under a 30 ft roof may protect nothing at 30 ft under a 36 ft roof. The clearance from the top of storage to the sprinkler deflector, 18 in. for standard spray sprinklers and 36 in. for most ESFR and CMSA designs, is part of the same rule set.

Arrangement is the third input. Palletized or solid-piled goods burn differently from goods in open racks, which let fire climb the flue spaces. Solid shelves in racks, open-top containers, shrink-wrapped (encapsulated) loads and very narrow aisles each shift the design. NFPA 13 has separate rules for each arrangement, which is why the same commodity at the same height can need a different system in a different rack layout.

The Storage Height Ladder

How the Fire Code and NFPA 13 Divide the Work

The fire code decides whether a storage area is regulated and what the building must provide; the sprinkler standard decides how the sprinkler system is designed. IFC Chapter 32 (or NFPA 1 Chapter 34 in Maryland and Delaware) is enforced by the fire code official, usually a fire marshal or fire prevention bureau. NFPA 13 is a referenced standard that both the building code and the fire code adopt, and the sprinkler design is reviewed by whoever reviews the construction permit.

IFC Chapter 32 answers five questions. Section 3201.1 and the Section 202 definitions set the 12 ft and 6 ft height triggers. Section 3201.2 ties the storage area to the operational permit in Chapter 1 (Section 105.5 in the 2021 and 2024 IFC, 105.6 in the 2018 IFC), which applies above 500 sq ft.

Section 3201.3 lists the construction documents, which the industry calls the high-piled storage plan. Table 3206.2 sets the building features required for each size of high-piled storage area, and Sections 3206 through 3209 add the rules for aisles, flue spaces, hose connections, smoke and heat removal, and automated storage. The Trigger article on when IFC Chapter 32 applies, linked in the questions table above, walks through the triggers in detail.

Table 3206.2 is the heart of the chapter. Its rows are ranges of high-piled storage area, from 500 sq ft up to more than 500,000 sq ft, split between Class I to IV and high-hazard commodities, and its columns are the building features: an automatic sprinkler system, fire detection, fire department access doors, smoke and heat removal, and the maximum pile dimension, storage height and pile volume for solid-piled, shelf and palletized storage. In the smaller size ranges of areas not open to the public the table offers two options, one with sprinklers designed for the storage and one without sprinklers but with detection, access doors and smoke and heat removal; areas open to the public must take the sprinkler option. The table itself is copyrighted ICC text and is not reproduced here; the high-piled storage plan cites the cell that applies.

NFPA 13 (2022) takes over once the sprinkler system has to be designed. Chapter 20 holds the general storage rules and commodity classification. Chapters 21, 22 and 23 give the ceiling-level design criteria for control mode density/area (CMDA), CMSA and ESFR sprinklers. Chapter 24 covers alternative designs based on listings and tests, and Chapter 25 covers in-rack sprinklers.

Delaware adopts the 2025 edition, which renumbers some of these sections, so a design that will be filed in Delaware should cite the 2025 text.

FM Global Data Sheet 8-9, Storage of Class 1, 2, 3, 4 and Plastic Commodities, is the insurer's version of the same rules. Where an FM-insured owner is involved, the design often has to satisfy both NFPA 13 and the data sheet, and the data sheet is sometimes more demanding on clearance, in-rack requirements and water supply duration. The code official enforces the code; the insurer enforces the data sheet through the policy.

Does IFC Chapter 32 Apply?

Two Documents, Two Jobs

IFC Chapter 32 (fire code)

• Decides whether the storage area is regulated: 12 ft or 6 ft triggers, 500 sq ft permit threshold
• Requires the high-piled storage plan and the operational permit (Sections 3201.2, 3201.3)
• Sets building features by area size: sprinklers, detection, access doors, smoke and heat removal (Table 3206.2); hose connections by Section 3206
• Sets aisle widths, flue spaces, pile dimensions and housekeeping (Sections 3206 to 3209)
• Enforced by the fire marshal or fire code official, renewed with the permit

NFPA 13 (2022) (sprinkler standard)

• Classifies the commodity: Class I to IV, Group A, B and C plastics (Chapter 20)
• Picks the ceiling design: CMDA or CMSA by commodity, storage height and ceiling height, ESFR by commodity and ceiling height (Chapters 21 to 23)
• Decides when in-rack sprinklers are required and how they are spaced (Chapter 25)
• Sets clearance to deflector, hose stream allowance and water supply duration
• Reviewed with the construction permit and the sprinkler shop drawings

What a High-Piled Storage Permit and Plan Cover

A high-piled storage permit is an operational permit issued by the fire code official that allows a building or part of a building over 500 sq ft to be used for high-piled storage. The permit is tied to the premises and the approved storage arrangement, not to the construction work, and it usually has to be renewed. In New York City the Fire Department of the City of New York (FDNY) issues the permit and inspects the premises each year before renewal; New Jersey has no separate fire permit for high-piled storage, so approval runs through the Uniform Construction Code permit and the local fire official enforces IFC Chapter 32 at inspection; in Maryland, NFPA 1 (2024) Section 1.13 (Table 1.13.8) lists a high-piled storage permit for areas over 500 sq ft, but the state amendments leave whether a permit is required to the local fire marshal's policy; Delaware deletes the NFPA 1 permit sections and approves high-piled storage through State Fire Marshal plan review; in Pennsylvania the requirement depends on whether the municipality has adopted the fire code.

The high-piled storage plan is the set of construction documents that IFC Section 3201.3 requires with the permit application. The plan shows the floor plan with the high-piled storage areas marked, the commodity classes stored in each area, the storage method (palletized, solid-piled, rack, shelf or bin box), the maximum storage height, the aisle widths and rack dimensions, the flue spaces, the sprinkler design basis including density and design area or the ESFR or CMSA listing, the fire detection and smoke removal provisions, the fire department access doors and hose connections, and the location of the water supply and fire pump if there is one. A fire protection engineer usually prepares the plan because the sprinkler design basis is the part most often wrong.

Cost and schedule follow the same three inputs. As of October 2026, a storage project whose existing sprinkler system already matches the commodity and height is mostly a documentation and review exercise measured in weeks. A project that needs in-rack sprinklers, a change from standard spray to ESFR, or a fire pump and tank because the municipal supply cannot carry the new demand is a construction project measured in months, and the water supply upgrade is usually the largest single line. The drivers are the commodity surprise found in the survey, the storage height the tenant insists on, the roof height and construction of the building, and the review queue at the fire marshal's office.

The permit and plan exist to freeze the three inputs: commodity, height and arrangement. A tenant that changes from cartoned goods to exposed plastics, raises the top load beam or installs solid shelving has changed the permit basis and in most jurisdictions needs an amended plan. The permit inspection is where fire marshals catch those changes, and the most common finding is storage that no longer matches the approved plan.

From Lease to Permit: The Sequence

Why Warehouses Outgrow Their Sprinklers (Commodity Creep)

Most high-piled storage problems are not design errors; they are buildings whose contents changed after the sprinklers were installed. A warehouse built in 2005 for cartoned Class III goods at 20 ft may now hold cartoned Group A plastics at 28 ft on taller racks for a new tenant. The sprinkler system did not change, but the fire it has to control did. Engineers call this commodity creep, and it is the single most common reason a fire marshal or an insurer rejects a storage occupancy.

Plastics are the usual driver. Under the mixed commodity rules in NFPA 13 (2022) Chapter 20, a Class III pallet load becomes Class IV once its Group A plastic content passes 5 percent, and Group A once nonexpanded plastic passes 15 percent by weight or expanded plastic passes 25 percent by volume (Sections 20.4.4 and 20.4.5). Plastic at 5 percent or less is ignored. Shrink-wrapped and plastic-encapsulated loads, plastic pallets, plastic totes and open-top bins each move a commodity up the scale. The Troubleshooting article on why open-top bins defeat rack sprinklers, linked in the questions table above, covers one of these cases.

Height and arrangement creep as well. Rack uprights get extended, a top beam level is added, a mezzanine is built, or wire decking is replaced with solid shelves. Each change can push the storage past the ceiling-only limits in NFPA 13 Chapters 21 to 23 and into Chapter 25 in-rack territory, or block the flue spaces the ceiling sprinklers rely on. When the water supply cannot support the new design, the fix becomes a fire pump or a tank, and the project cost changes by an order of magnitude.

The way to catch commodity creep is to compare the stored goods against the sprinkler design basis every time a tenant, a product line or a rack layout changes, not only at permit renewal. The Comparison article on ESFR and CMSA sprinklers, linked in the questions table above, explains why the two ceiling-only options have different ceilings for commodity creep.

Inside a Double-Row Rack: Flues, Clearance and In-Rack Heads

What Insurers Add on Top of the Code

The fire code sets the minimum a building must have; the property insurer sets what it will insure at a given rate. For storage occupancies the two often differ, because an insurer is protecting the inventory and the business interruption, while the code is protecting the people and the neighboring buildings. FM Global and the larger carriers write their own storage protection standards, and FM Global Data Sheet 8-9 is the one most owners in the region meet.

The insurer's version is usually stricter in four places. It may require in-rack sprinklers at lower storage heights than NFPA 13 allows for ceiling-only protection, especially for exposed plastics. It may require a longer water supply duration and a larger hose stream allowance. It may limit the use of ESFR sprinklers under certain roof constructions or with certain obstructions.

It will almost always require a loss prevention inspection in which the stored goods are compared against the design basis, which is where commodity creep is most often found.

An owner who meets the code but not the data sheet keeps the permit and loses the preferred rate, or receives a recommendation with a deadline. An owner who designs to the data sheet from the start usually meets the code with margin to spare. The decision belongs to the owner and the broker, and the high-piled storage plan should say which basis was used so the fire marshal and the insurer are reading the same document.

Who Needs to Act

The owner holds the permit and is responsible for the building features in Table 3206.2 and for keeping the sprinkler design basis on file. The tenant controls the commodity, the height and the arrangement day to day, and is the party that most often changes them without telling anyone. The broker or developer decides which buildings a storage tenant can realistically occupy, and a commodity and height check before the lease is signed is the cheapest fire protection decision in the whole sequence. The architect or fire protection engineer prepares the high-piled storage plan and the sprinkler design criteria, and the sprinkler contractor turns the criteria into shop drawings and an installed system that the fire marshal and the insurer both accept.

Code Editions by State

High-piled storage is regulated by a different document, a different edition and a different official in each of the six jurisdictions DGA works in. The table lists the fire code basis for Chapter 32 or Chapter 34, the sprinkler standard edition, the authority having jurisdiction (AHJ) and the name of the filing, as of October 2026. Local amendments are not shown.

Editions as listed in DGA's Fire Code Cheat Sheet for NY, NJ, PA, MD and DE (linked below). Confirm local amendments with the AHJ before filing.

Key Concepts

These are the terms the Storage and Commodities articles use. Each is defined once here so the spokes can use the term without re-explaining it.

• High-piled combustible storage: storage of combustible materials in closely packed piles or on racks, shelves or pallets above 12 ft, or, where the fire code official requires it, above 6 ft for high-hazard commodities, as defined in IFC Section 202. NFPA 1 (2024) uses 5 ft for Group A plastics.
• Commodity classification: the NFPA 13 system that sorts stored goods and their packaging into Class I through IV and Group A, B and C plastics by how much heat they release when burning.
• Group A plastics: the highest-hazard common commodity group, including polyethylene, polypropylene, polystyrene, nylon, PVC with more than 20 percent plasticizer and most rubber, which needs the most demanding sprinkler design.
• Encapsulation: a pallet load wrapped in plastic on the top and all sides, which traps heat and blocks sprinkler water and therefore raises the design requirement.
• Flue space: the open vertical gap between pallet loads in a rack, transverse between loads in a row and longitudinal between the two rows of a double-row rack, that lets ceiling sprinkler water reach a fire low in the rack.
• Clearance to deflector: the vertical distance from the top of storage to the sprinkler deflector, at least 18 in. for standard spray sprinklers and 36 in. for ESFR and CMSA sprinklers under NFPA 13.
• Ceiling-only protection: a sprinkler design that controls or suppresses a storage fire using sprinklers at the roof alone, which is available only up to the storage and ceiling heights listed in NFPA 13 Chapters 21 to 23.
• In-rack sprinklers: sprinklers installed inside the rack structure at one or more levels, governed by NFPA 13 Chapter 25, required when storage is too high or too hazardous for ceiling-only protection.
• ESFR (early suppression fast response) sprinkler: a large-orifice, fast-acting sprinkler designed to suppress rather than control a storage fire, which permits ceiling-only protection of many commodities under ceilings up to 45 ft.
• CMSA (control mode specific application) sprinkler: a large-drop type sprinkler listed for specific storage applications, designed to control a fire with fewer operating heads than standard spray.
• High-piled storage plan: the construction documents required by IFC Section 3201.3 that show the storage areas, commodity classes, heights, arrangement, aisles, flue spaces and the fire protection design basis.
• Commodity creep: the gradual change in stored goods, heights or arrangement after a sprinkler system is installed, which leaves the system designed for a smaller fire than the one it now faces.

Working With DGA on High-Piled Storage

DGA's engineers evaluate storage occupancies for owners, tenants and brokers before a lease or purchase, prepare high-piled storage plans and sprinkler design criteria for permits, and review existing sprinkler systems against the goods a tenant actually intends to store. The scope of work and the fee drivers are described on the high-piled storage and commodity classification service page, and the kinds of buildings DGA works in are described on the industrial and high-hazard sector page.

DGA prepares high-piled storage plans, commodity classifications and sprinkler design criteria for warehouses and distribution centers across New York, New Jersey, Pennsylvania, Maryland and Delaware. Project briefs get confirmation and preliminary code feedback within one business day. See where DGA works →

Two tools support the first conversation. The Sprinkler Water Supply Analysis tool compares a hydrant flow test against a storage sprinkler demand and shows whether the supply can carry an ESFR or in-rack design before anyone draws it. The Fire Code Cheat Sheet lists the adopted code and standard editions for every jurisdiction in the region so the design cites the right text from the start.

Frequently Asked Questions

This guide is general information, not a code determination for any project. Code editions, local amendments and reviewer practice change; confirm the adopted code and the authority having jurisdiction before relying on any threshold or section cited here.