High-Piled Plastic Storage Under Existing ESFR Sprinklers
An 80,000-square-foot single-story warehouse has an existing ESFR sprinkler system designed for a 30-foot ceiling and 20-foot storage of Class III commodities. The owner now proposes 24-foot-high double-row rack storage of Group A plastic toys in cartons, with 8-foot aisles and solid shelves. The existing fire pump is rated 750 gpm at 60 psi; the new rack storage design submitted by the owner’s consultant shows a demand of 1,250 gpm at 70 psi, but the consultant states the existing ESFR heads “are listed for 25 feet” and asks for approval without changing the pump. The owner wants to occupy the first 40,000 square feet immediately and defer the sprinkler and pump upgrades for six months. The building has one fire department connection and a 12-inch water main. The fire code official must decide whether the existing system can support the proposed storage, what permits are required, and whether partial occupancy can be allowed.
1. Evaluate whether the existing ESFR sprinkler system can support the proposed Group A plastic rack storage. What information is missing?
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The consultant’s statement is not enough. ESFR sprinklers are listed for specific ceiling heights, storage heights, commodities and rack arrangements. Group A plastic toys in cartons on solid shelves in double-row racks are a more challenging commodity than Class III, and 24-foot storage may exceed the listing or design basis for the existing heads. The submitted demand of 1,250 gpm at 70 psi also exceeds the 750 gpm at 60 psi pump, so the existing system cannot meet the new demand even if the heads are listed for 25 feet. I would require the commodity classification, rack section, aisle width, ceiling height, shelf type, listing data and hydraulic calculations. Until those show the existing system is adequate-or upgrades are designed-the new storage cannot be approved.
2. What permits and submittals are required for the storage change and any sprinkler or pump upgrade?
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The project needs a high-piled storage permit and a new plan review, not a storage-change notice. Submittals should include the rack layout, commodity classification, ESFR listing and design criteria, hydraulic calculations, fire pump curve and test data, water supply, and structural/electrical work for any pump or head changes. If the pump is replaced or upgraded, fire pump acceptance testing and electrical coordination are required. The fire department connection and water main capacity should be verified. Because the owner wants to defer upgrades, I would require a phasing plan that keeps unapproved storage out of the building; “defer” cannot mean storing the new commodity under the old design.
3. Can the owner occupy the first 40,000 square feet while the upgrades are deferred? What conditions would you set?
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Partial occupancy of 40,000 square feet could be considered only if that area is separated from the unapproved storage by an approved fire barrier and the occupied area is limited to the existing approved commodity and height. It cannot contain the Group A plastic rack storage. I would require a physical boundary, signage, and an inspection before occupancy. A fire watch is not a substitute for sprinkler inadequacy. If the owner wants to use the new storage before upgrades, the storage height and commodity must be reduced to what the existing ESFR design supports, documented by the designer and accepted by the code official. Otherwise occupancy should wait.