Issue DS 2018-043: The petitioner Allen R. Finfrock of Finfrock DMC is seeking a declaratory statement on if the fire barrier of a floor and ceiling assembly is the ceiling, would the continuity of a fire barrier be maintained if the barrier stops at the ceiling and the joint is sealed in accordance with Section 707.8?

Background:

Finfrock is a design/build/manufacturer who has patented a precast concrete floor and ceiling assembly called the "Dual Deck" that consists of two layers of concrete separated by a steel truss system. This system has a UL listing for a two-hour fire rating. The bottom (ceiling) slab is the fire barrier and the top (floor) slab creates the interstitial space. Finfrock is seeking clarification on the 2017 Florida Building Code, Section 707, Fire Barriers, and Section 707.5, Continuity, to insure that the interpretation between various jurisdictions is consistent with the intent of the code and is consistent with the corresponding section in the Florida Fire Prevention Code, Section 8.3 (code excerpt below). In the past, different jurisdictions have had varying interpretations as to the intent of the code as it applies to a floor and ceiling assembly.

Finfrock is designing a nine story multifamily building for the Orlando area. This project will be constructed using precast concrete products which will include exterior walls, shear walls, supporting walls for double tees (garage area) and dualDecks (floor and ceiling assembly). The building will have an interior stair well with a corridor leading to the exterior. The code requires that this corridor be considered as an extension of the 2-hour rated stairway exit. As such, it is considered and “exist passageway” which is required to be constructed with “fire barrier” in lieu of a “fire partition”. Fire barrier walls have the “continuity” requirements per FBC Section 707.5. The corridor will have a precast concrete Dual Deck as it’s’ ceiling. Drawings are attached for clarification.

2017 Florida Building Code 6^th Edition

[A]101.4.5 Fire prevention.

For provisions related to fire prevention, refer to the Florida Fire Prevention Code. The Florida Fire Prevention Code shall apply to matters affecting or relating to structures, processes and premises from the hazard of fire and explosion arising from the storage, handling or use of structures, materials or devices; from conditions hazardous to life, property or public welfare in the occupancy of structures or premises; and from the construction, extension, repair, alteration or removal of fire suppression, and alarm systems or fire hazards in the structure or on the premises from occupancy or operation.

707.5 Continuity.

Fire barriers shall extend from the top of the foundation or floor/ceiling assembly below to the underside of the floor or roof sheathing, slab or deck above and shall be securely attached thereto. Such fire barriers shall be continuous through concealed space, such as the space above a suspended ceiling. Joints and voids at intersections shall comply with Sections 707.8 and 707.9

Exceptions:

1. Shaft enclosures shall be permitted to terminate at a top enclosure complying with Section 713.12.

2. Interior exit stairway and ramp enclosures required by Section 1023 and exit access stairway and ramp enclosures required by Section 1019 shall be permitted to terminate at a top enclosure complying with Section 713.12.

707.8 Joints.

Joints made in or between fire barriers, and joints made at the intersection of fire barriers with underside of a fire-resistance-rated floor or roof sheathing, slab or deck above, and the exterior vertical wall intersection shall comply with Section 715.

715.1 General.

Joints installed in or between fire-resistance-rated walls, floor or floor/ceiling assemblies and roofs or roof/ceiling assemblies shall be protected by an approved fire-resistant joint system designed to resist the passage of fire for a time period not less than the required fire-resistance rating of the wall, floor or roof in or between which the system is installed. Fire-resistant joint systems shall be tested in accordance with Section 715.3.

2018 Florida Fire Prevention Code 6^th Edition

Section 8.3 - Fire Barriers

8.3.1.2(2) - The fire barriers are continuous from outside wall to outside wall or from one fire barrier to another, and from the floor to the bottom of the interstitial space, provided that the construction assembly forming the bottom of the interstitial space has a fire resistance rating not less than that of the fire barrier.

Staff Analysis:

Question : If the fire barrier of a floor and ceiling assembly is the ceiling, would the continuity of a fire barrier be maintained if the barrier stops at the ceiling and the joint is sealed in accordance with Section 707.8?

Answer: The application of the product in question “a precast concrete floor and ceiling assemble (DualDeck)” is a proposed alternative to the prescribed fire barrier continuity provisions of Sections 707.5 of the 6^th Edition (2017) Florida Building Code “FBC”, Building. As per Sections 104.11 of the 6^th Edition (2017) Florida Building Code, Building, an alternative method of construction to that prescribed in the FBC is subject to review and approval by the local building official, when such alternative is substantiated to be equivalent of that prescribed in the FBC in quality, strength, effectiveness, durability and safety.