3.1.5.

(1) Except as permitted by Sentences (2) to (4) and Articles 3.1.5.2. to 3.1.5.25., 3.1.13.4. and 3.2.2.16., a building or part of a building required to be of noncombustible construction, shall be constructed with noncombustible materials.

(2) Notwithstanding the definition for noncombustible materials stated in Article 1.4.1.2.v1v2v3v4v5 of Division A, a material is permitted to be used in noncombustible construction provided that, when tested in accordance with CAN/ULC-S135, “Test Method for the Determination of Combustibility Parameters of Building Materials Using an Oxygen Consumption Calorimeter (Cone Calorimeter)” at a heat flux of 50 kW/m²,

(a) its average total heat release is not more than 3 MJ/m²,

(b) its average total smoke extinction area is not more than 1.0 m², and

(c) the test duration is extended beyond the time stipulated in the referenced standard until it is clear that there is no further release of heat or smoke.

(3) If a material referred to in Sentence (2), consists of a number of discrete layers and testing reveals that the surface layer or layers protects the underlying layers such that the complete combustion of the underlying layers does not occur, the test shall be repeated by removing the outer layers sequentially until all layers have been exposed during testing, or complete combustion has occurred.

(4) The acceptance criteria for a material tested in accordance with Sentence (3) shall be based on the cumulative emissions from all layers, which must not exceed the criteria stated in Clauses (2)(a) and (2)(b).

(1) The following minor combustible components are permitted in a building required to be of noncombustible construction:

(a) paint,

(b) mastics and caulking materials applied to provide flexible seals between the major components of exterior wall construction,

(c) fire stop materials conforming to Sentence 3.1.9.1.(1) and Article 3.1.11.7.,

(d) tubing for pneumatic controls provided it has an outside diameter not more than 10 mm,

(e) adhesives, vapour barriers and sheathing papers,

(f) electrical outlet and junction boxes,

(g) wood blocking within wall assemblies intended for the attachment of handrails, fixtures, and similar items mounted on the surface of the wall, and

(h) similar minor components.

(1) Combustible roof covering that has an A, B, or C classification determined in conformance with Subsection 3.1.15. is permitted on a building required to be of noncombustible construction.

(2) Combustible roof sheathing and roof sheathing supports installed above a concrete deck are permitted on a building required to be of noncombustible construction provided,

(a) the concrete deck is not less than 50 mm thick,

(b) the height of the roof space above the deck is not more than 1 000 mm,

(c) the roof space is divided into compartments by fire stops in conformance with Article 3.1.11.5.,

(d) openings through the concrete deck other than for noncombustible roof drains and plumbing piping are protected by masonry or concrete shafts,

(i) constructed as fire separations having a fire-resistance rating not less than 1 h, and

(ii) extending from the concrete deck to not less than 150 mm above the adjacent roof sheathing,

(e) the perimeter of the roof is protected by a noncombustible parapet extending from the concrete deck to not less than 150 mm above the adjacent sheathing, and

(f) except as permitted by Clause (d), the roof space does not contain any building services.

(3) Combustible cant strips, roof curbs, nailing strips and similar components used in the installation of roofing are permitted on a building required to be of noncombustible construction.

(4) Wood nailer facings to parapets, not more than 600 mm high, are permitted on a building required to be of noncombustible construction, if the facings and any roof membranes covering the facings are protected by sheet metal.

(1) Combustible skylight assemblies are permitted in a building required to be of noncombustible construction if the assemblies have a flame-spread rating not more than,

(a) 150 provided the assemblies,

(i) have an individual area not more than 9 m²,

(ii) have an aggregate horizontal projected area of the openings through the ceiling not more than 25% of the area of the ceiling of the room or space in which they are located, and

(iii) are spaced not less than 2 500 mm from adjacent assemblies and 1 200 mm from required fire separations, or

(b) 75 provided the assemblies,

(i) have an individual area not more than 27 m²,

(ii) have an aggregate horizontal projected area of the openings through the ceiling not more than 33% of the area of the ceiling of the room or space in which they are located, and

(iii) are spaced not less than 1 200 mm from adjacent assemblies and from required fire separations.

(2) Combustible vertical glazing installed no higher than the second storey is permitted in a building required to be of noncombustible construction.

(3) Except as permitted by Sentence (4), the combustible vertical glazing permitted by Sentence (2) shall have a flame-spread rating not more than 75.

(4) The flame-spread rating of combustible glazing in Sentence (2) is permitted to be not more than 150 if the aggregate area of glazing is not more than 25% of the wall area of the storey in which it is located, and

(a) the glazing is installed in a building not more than 1 storey in building height,

(b) the glazing in the first storey is separated from the glazing in the second storey in accordance with the requirements of Article 3.2.3.17. for opening protection, or

(c) sprinklers are installed in,

(i) any storey with combustible glazing, and

(ii) the storey immediately above the storey with combustible glazing.

(5) Combustible window sashes and frames are permitted in a building required to be of noncombustible construction provided,

(a) each window in an exterior wall face is an individual unit separated by noncombustible wall construction from every other opening in the wall,

(b) windows in exterior walls in contiguous storeys are separated by not less than 1 000 mm of noncombustible construction, and

(c) the aggregate area of openings in an exterior wall face of a fire compartment is not more than 40% of the area of the wall face.

(1) Except for an exposing building face required to conform to Sentence 3.2.3.7.(1) or Sentence 3.2.3.7.(4), an exterior non-loadbearing wall assembly that includes combustible components is permitted to be used in a building required to be of noncombustible construction provided,

(a) the building is,

(i) not more than 3 storeys in building height, or

(ii) not more than 6 storeys in building height if sprinklered,

(b) the interior surfaces of the wall assembly are protected by a thermal barrier conforming to Sentence 3.1.5.11.(3), and

(c) the wall assembly satisfies the criteria of Sentences (2) and (3) when subjected to testing in conformance with CAN/ULC-S134, “Fire Test of Exterior Wall Assemblies”.

(2) Flaming on or in the wall assembly shall not spread more than 5 m above the opening during the test procedure referenced in Sentence (1).

(3) The heat flux during the flame exposure on a wall assembly shall be not more than 35 kW/m² measured 3.5 m above the opening during the test procedure referenced in Sentence (1).

(4) A wall assembly permitted by Sentence (1) that includes combustible cladding of fire-retardant treated wood shall be tested for fire exposure after the cladding has been subjected to an accelerated weathering test as specified in ASTM D2898, “Accelerated Weathering on Fire-Retardant-Treated Wood for Fire Testing”.

(5) The requirements in this Article do not apply where foamed plastic insulation is used in an exterior wall assembly of a building and the insulation is protected in conformance with Sentences 3.2.3.8.(1) and (2).

(1) Wood nailing elements attached directly to or set into a continuous noncombustible backing for the attachment of interior finishes, are permitted in a building required to be of noncombustible construction provided the concealed space created by the wood elements is not more than 50 mm thick.

(1) Combustible millwork including interior trim, doors and door frames, show windows together with their frames, aprons and backing, handrails, shelves, cabinets and counters is permitted in a building required to be of noncombustible construction.

(1) Combustible stage flooring supported on noncombustible structural members is permitted in a building required to be of noncombustible construction.

(2) Wood members more than 50 mm but not more than 375 mm high applied directly to or set into a noncombustible floor slab are permitted for the construction of a raised platform in a building required to be of noncombustible construction provided the concealed spaces are fire stopped in conformance with Sentence 3.1.11.3.(2).

(3) The floor system for the raised platform referred to in Sentence (2) is permitted to include combustible subfloor and combustible finished flooring.

(4) Combustible finished flooring is permitted in a building required to be of noncombustible construction.

(1) Combustible stairs are permitted in a dwelling unit in a building required to be of noncombustible construction.

(1) Combustible interior finish, including paint, wallpaper, and other interior finishes not more than 1 mm thick, is permitted in a building required to be of noncombustible construction.

(2) Combustible interior wall finishes, other than foamed plastics, are permitted in a building required to be of noncombustible construction provided they,

(a) are not more than 25 mm thick, and

(b) have a flame-spread rating not more than 150 on any exposed surface, or any surface that would be exposed by cutting through the material in any direction.

(3) Combustible interior ceiling finishes, other than foamed plastics, are permitted in a building required to be of noncombustible construction provided they,

(a) are not more than 25 mm thick, except for exposed fire-retardant treated wood battens, and

(b) have a flame-spread rating not more than 25 on any exposed surface, or on any surface that would be exposed by cutting through the material in any direction, or are of fire-retardant treated wood, except that not more than 10% of the ceiling area within each fire compartment is permitted to have a flame-spread rating not more than 150.

(1) Gypsum board with a tightly adhering paper covering not more than 1 mm thick is permitted in a building required to be of noncombustible construction provided the flame-spread rating of the surface is not more than 25.

(1) Combustible insulation, other than foamed plastics, is permitted in a building required to be of noncombustible construction provided that it has a flame-spread rating not more than 25 on any exposed surface, or any surface that would be exposed by cutting through the material in any direction, where the insulation is not protected as described in Sentences (3) and (4).

(2) Foamed plastic insulation having a flame-spread rating not more than 25 on any exposed surface, or any surface that would be exposed by cutting through the material in any direction, is permitted in a building required to be of noncombustible construction provided the insulation is protected from adjacent space in the building, other than adjacent concealed spaces within wall assemblies, by a thermal barrier consisting of,

(a) not less than 12.7 mm thick gypsum board mechanically fastened to a supporting assembly independent of the insulation,

(b) lath and plaster, mechanically fastened to a supporting assembly independent of the insulation,

(c) masonry,

(d) concrete, or

(e) any thermal barrier that meets the requirements of classification B when tested in conformance with CAN4-S124-M, “Test for the Evaluation of Protective Coverings for Foamed Plastic”.

(3) Combustible insulation having a flame-spread rating more than 25 but not more than 500 on an exposed surface, or any surface that would be exposed by cutting through the material in any direction, is permitted in the exterior walls of a building required to be of noncombustible construction, provided the insulation is protected from adjacent space in the building, other than adjacent concealed spaces within wall assemblies, by a thermal barrier as described in Sentence (2), except that in a building that is not sprinklered and is more than 18 m high, measured between grade and the floor level of the top storey, or in a building that is not sprinklered and is regulated by the provisions of Subsection 3.2.6., the insulation shall be protected by a thermal barrier consisting of,

(a) gypsum board not less than 12.7 mm thick, mechanically fastened to a supporting assembly independent of the insulation and with all joints either backed or taped and filled,

(b) lath and plaster, mechanically fastened to a supporting assembly independent of the insulation,

(c) masonry or concrete not less than 25 mm thick, or

(d) any thermal barrier that, when tested in conformance with CAN/ULC-S101-M, “Fire Endurance Tests of Building Construction and Materials”, will not develop an average temperature rise more than 140°C or a maximum temperature rise more than 180°C at any point on its unexposed face within 10 min.

(4) Combustible insulation having a flame-spread rating more than 25 but not more than 500 on any exposed surface, or any surface that would be exposed by cutting through the material in any direction, is permitted in the interior walls, within ceilings and within roof assemblies of a building required to be of noncombustible construction, provided the insulation is protected from adjacent space in the building, other than adjacent concealed spaces within wall assemblies, by a thermal barrier as described in Sentence (2), except that in a building that is not sprinklered and is more than 18 m high, measured between grade and the floor level of the top storey, or in a building that is not sprinklered and is regulated by the provisions of Subsection 3.2.6., the insulation shall be protected by a thermal barrier consisting of,

(a) Type X gypsum board not less than 15.9 mm thick, mechanically fastened to a supporting assembly independent of the insulation and with all joints either backed or taped and filled, conforming to,

(i) CAN/CSA-A82.27-M, “Gypsum Board”,

(ii) ASTM C36 / C36M, “Gypsum Wallboard”,

(iii) ASTM C442 / C422M, “Gypsum Backing Board, Gyspum Coreboard, and Gypsum Shaftliner Board”,

(iv) ASTM C588 / C588M, “Gypsum Base for Veneer Plasters”,

(v) ASTM C630 / C630M, “Water-Resistant Gypsum Backing Board”,

(vi) ASTM C931 / C931M, “Exterior Gypsum Soffit Board”, or

(vii) ASTM C960 / C960M, “Predecorated Gypsum Board”,

(b) non-loadbearing masonry or concrete not less than 50 mm thick,

(c) loadbearing masonry or concrete not less than 75 mm thick, or

(d) any thermal barrier that, when tested in conformance with CAN/ULC-S101-M, “Fire Endurance Tests of Building Construction and Materials”,

(i) will not develop an average temperature rise more than 140°C or a maximum temperature rise more than 180°C at any point on its unexposed face within 20 min, and

(ii) will remain in place for not less than 40 min.

(5) Combustible insulation, including foamed plastics, installed above roof decks, outside of foundation walls below ground level and beneath concrete slabs-on-ground is permitted to be used in a building required to be of noncombustible construction.

(6) Thermosetting foamed plastic insulation having a flame-spread rating not more than 500 that forms part of a factory-assembled exterior wall panel that does not incorporate an air space is permitted to be used in a building required to be of noncombustible construction provided,

(a) the foamed plastic is protected on both sides by sheet steel not less than 0.38 mm thick that will remain in place for not less than 10 min when the wall panel is tested in conformance with CAN/ULC-S101-M, “Fire Endurance Tests of Building Construction and Materials”,

(b) the flame-spread rating of the wall panel, determined by subjecting a sample including an assembled joint to the appropriate test described in Subsection 3.1.12., is not more than the flame-spread rating permitted for the room or space that it bounds,

(c) the building does not contain a Group B or Group C major occupancy, and

(d) the building is not more than 18 m high, measured between grade and the floor level of the top storey.

(7) A factory-assembled non-loadbearing interior or exterior wall or ceiling panel containing foamed plastic insulation having a flame-spread rating of not more than 500 is permitted to be used in a building required to be of noncombustible construction provided,

(a) the building is sprinklered,

(b) the building is not more than 18 m high, measured between grade and the floor level of the uppermost storey,

(c) the building does not contain a Group A, Group B, or Group C major occupancy,

(d) the panel does not contain an air space,

(e) the panel, when tested in conformance with ULC/ORD-C376, “Fire Growth of Foamed Plastic Insulated Building Panels in a Full-Scale Room Configuration”, meets the criteria defined in the document, and

(f) the flame-spread rating of a panel, determined by subjecting a sample, including an assembled joint typical of field installation, to the appropriate test described in Subsection 3.1.12., is not more than the flame-spread rating permitted for the room or space that it bounds.

(1) Except as permitted by Sentence (2), solid lumber partitions not less than 38 mm thick and wood framing in partitions located in a fire compartment not more than 600 m² in area are permitted to be used in a building required to be of noncombustible construction in a floor area that is not sprinklered provided the partitions,

(a) are not required fire separations, and

(b) are not located in a care or detention occupancy.

(2) Partitions installed in a building of noncombustible construction are permitted to contain wood framing provided,

(a) the building is not more than 3 storeys in building height,

(b) the partitions are not located in a care or detention occupancy, and

(c) the partitions are not installed as enclosures for exits or vertical service spaces.

(3) Solid lumber partitions not less than 38 mm thick and partitions that contain wood framing are permitted to be used in a building required to be of noncombustible construction provided,

(a) the floor area containing the partitions is sprinklered, and

(b) the partitions are not,

(i) located in a care or detention occupancy,

(ii) installed as enclosures for exits or vertical service spaces, or

(iii) used to satisfy the requirements of Clause 3.2.8.1.(1)(a).

(1) Storage lockers in storage rooms are permitted to be constructed of wood in a building of residential occupancy required to be of noncombustible construction.

(1) Except as required by Sentence 3.6.4.3.(1), combustible ducts, including plenums and duct connectors, are permitted to be used in a building required to be of noncombustible construction provided these ducts and duct connectors are used only in horizontal runs.

(2) Combustible duct linings, duct coverings, duct insulation, vibration isolation connectors, duct tape, pipe insulation and pipe coverings are permitted to be used in a building required to be of noncombustible construction provided they conform to the appropriate requirements of Part 6.

(3) In a building required to be of noncombustible construction, combustible ducts need not comply with the requirements of Part 6 provided the ducts are,

(a) part of a duct system conveying only ventilation air, and

(b) contained entirely within a dwelling unit.

(1) Except as permitted by Clause 3.1.5.2.(1)(d) , Sentences (2) and (3), and Article 3.1.5.22., combustible piping and tubing and associated adhesives are permitted to be used in a building required to be of noncombustible construction provided that, except when concealed in a wall or concrete floor slab, they,

(a) have a flame-spread rating not more than 25, and

(b) if used in a building described in Subsection 3.2.6.v1, have a smoke developed classification not more than 50.

(2) Combustible sprinkler piping is permitted to be used within a sprinklered floor area in a building required to be of noncombustible construction.

(3) Polypropylene pipes and fittings are permitted to be used for drain, waste and vent piping for the conveyance of highly corrosive materials and for piping used to distribute distilled or dialyzed water in laboratory and hospital facilities in a building required to be of noncombustible construction, provided,

(a) the building is sprinklered,

(b) the piping is not located in a vertical shaft, and

(c) piping that penetrates a fire separation is sealed at the penetration by a fire stop system that, when subjected to the fire test method in CAN4-S115-M, “Fire Tests of Firestop Systems”, has an FT rating not less than the fire-resistance rating of the fire separation.

(1) Combustible plumbing fixtures are permitted in a building required to be of noncombustible construction if they are constructed of material having a flame-spread rating and smoke developed classification permitted in Subsection 3.1.13.

(1) Except as permitted by Articles 3.1.5.19. and 3.1.5.21., optical fibre cables and electrical wires and cables with combustible insulation, jackets or sheathes are permitted in a building required to be of noncombustible construction, provided,

(a) the wires and cables exhibit a vertical char of not more than 1.5 m when tested in conformance with the Vertical Flame Test – Cables in Cabletrough in Clause 4.11.4. of CAN/CSA-C22.2 No. 0.3, “Test Methods for Electrical Wires and Cables” (FT4 Rating),

(b) the wires and cables are located in,

(i) totally enclosed noncombustible raceways,

(ii) concealed spaces in walls,

(iii) concrete slabs,

(iv) a service room separated from the remainder of the building by a fire separation having a fire-resistance rating not less than 1 h, or

(v) totally enclosed nonmetallic raceways conforming to Article 3.1.5.20.v1, or

(c) the wires and cables are communication cables used at the service entry to a building and are not more than 3 m long.

(2) The requirement in Clause (1)(a) is considered to be met where the wires and cables exhibit a flame-spread of not more than 1.5 m, a smoke density of not more than 0.5 at peak optical density and a smoke density not more than 0.15 at average optical density when tested in conformance with the Flame and Smoke Test in the Appendix to CSA C22.2 No. 0.3, “Test Methods for Electrical Wires and Cables” (FT6 Rating).

(1) Combustible travelling cables are permitted on elevating devices in a building required to be of noncombustible construction.

(1) Subject to limits on size for penetrations of fire separations as required by Sentence 3.1.9.3.(2), within a fire compartment of a building required to be of noncombustible construction, totally enclosed nonmetallic raceways not more than 175 mm in outside diameter, or an equivalent rectangular area, are permitted to be used to enclose optical fibre cables and electrical wires and cables, provided the raceways exhibit a vertical char not more than 1.5 m when tested in conformance with the Test for Flame Propagation (Riser) in Section 3.4 of the ULC/ORD-C2024, “Fire Tests for Optical Fibre Cable Raceways” (FT-4 rating).

(1) Optical fibre cables and electrical wires and cables with combustible insulation, jackets or sheathes, located in the space below a raised floor in a computer room, are permitted in a building required to be of noncombustible construction provided they do not convey flame or continue to burn for more than 1 min when tested in conformance with the Vertical Flame Test in Clause 4.11.1. of CSA C22.2 No. 0.3, “Test Methods for Electrical Wires and Cables” (FT1 Rating).

(2) The requirement in Sentence (1) is considered to be met where the wires and cables

(a) exhibit a vertical char of not more than 1.5 m when tested in conformance with the Vertical Flame Test — Cables in Cabletrough in Clause 4.11.4. of CSA C22.2 No. 0.3, “Test Methods for Electrical Wires and Cables” (FT4 Rating), or

(b) exhibit a flame-spread of not more than 1.5 m, a smoke density of not more than 0.5 at peak optical density and a smoke density not more than 0.15 at average optical density when tested in conformance with the Flame and Smoke Test in the Appendix to CSA C22.2 No. 0.3, “Test Methods for Electrical Wires and Cables” (FT6 Rating).

(1) Combustible fittings and components in a public pool or public spa, including main drains, piping, skimmers, return inlets, steps, ladder rungs and liners, are permitted in a building required to be of noncombustible construction.

(1) Except as permitted in Sentence (2), exterior marquees, not greater than 7.5 m from ground level to the top of the marquee, having combustible elements other than fabrics or films conforming to Sentence 3.1.16. 1.(1), are permitted on a building required to be of noncombustible construction, provided every opening in the exposed wall of the building above the marquee is protected with wired glass in accordance with Supplementary Standard SB-2 where these openings are within,

(a) 4.5 m horizontally of the marquee, and

(b) 9 m vertically above the marquee.

(2) The protection required by Sentence (1) is permitted to be waived if the building is sprinklered.

(1) In a building required to be of noncombustible construction, a mezzanine located within a live/work unit is permitted to be of combustible construction provided the area of the mezzanine is not more than 25% of the floor area of the live/work unit or 20 m², whichever is less, and has no obstructions more than 1 070 mm above the floor.

(1) Wood decorative cladding is permitted to be used on exterior marquee fascias, of a storey having direct access to a street or access route, of a building required to be of noncombustible construction provided the cladding is fire-retardant treated wood that, before testing to CAN/ULC-S102-M, “Test for Surface Burning Characteristics of Building Materials and Assemblies,” has been conditioned in conformance with ASTM D 2898, “Accelerated Weathering of Fire-Retardant Treated Wood for Fire Testing”.

(1) A combustible solar collector system is permitted to be installed above the roof of a building required to be of non-combustible construction.