6.2.4.8 — Coverings, Linings and Insulation

(1) Foamed plastic insulation is permitted to be installed above roof decks, outside of foundation walls below ground level and beneath concrete slabs-on-ground of a building required to be of noncombustible construction. (2) Except as provided in Sentences (3) and (4), foamed plastic insulation with a flame-spread rating 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 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 that, (a) consists of not less than 12.7 mm thick gypsum board mechanically fastened to a supporting assembly independent of the insulation, (b) consists of lath and plaster, mechanically fastened to a supporting assembly independent of the insulation, (c) consists of masonry, (d) consists of concrete, or (e) meets the requirements of classification B when tested in conformance with CAN/ULC-S124, “Test for the Evaluation of Protective Coverings for Foamed Plastic”. (3) Foamed plastic insulation with 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 exterior walls of a building required to be of noncombustible construction, that is not sprinklered and is more than 18 m high, measured from grade to the underside of the roof, provided the insulation is protected from adjacent space in the building, other than adjacent concealed spaces within wall assemblies, by a thermal barrier that, (a) consists of 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) consists of lath and plaster, mechanically fastened to a supporting assembly independent of the insulation, (c) consists of masonry or concrete not less than 25 mm thick, or (d) when tested in conformance with CAN/ULC-S101, “Fire Endurance Tests of Building Construction and Materials”, does 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) Foamed plastic insulation with 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, that is not sprinklered and is more than 18 m high, measured from grade to the underside of the roof, provided the insulation is protected from adjacent space in the building, other than adjacent concealed spaces within wall assemblies, by a thermal barrier that, (a) consists of 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) ASTM C1177 / C1177M, “Glass Mat Gypsum Substrate for Use as Sheathing”, (ii) ASTM C1178 / C1178M, “Coated Glass Mat Water-Resistant Gypsum Backing Panel”, (iii) ASTM C1396 / C1396M, “Gypsum Board”, or (iv) CAN/CSA-A82.27-M, “Gypsum Board”, (b) consists of non-loadbearing masonry or concrete not less than 50 mm thick, (c) consists of loadbearing masonry or concrete not less than 75 mm thick, or (d) when tested in conformance with CAN/ULC-S101, “Fire Endurance Tests of Building Construction and Materials”, (i) does 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) remains in place for not less than 40 min.

(1) Tape used for sealing joints in air ducts, plenums and other parts of air duct systems shall meet the flame-resistance requirements for fabric in CAN/ULC-S109, “Flame Tests of Flame-Resistant Fabrics and Films”.

(1) Except as provided in Sentences (2) and (4), foamed plastics that form part of a wall or ceiling assembly shall be protected from adjacent space in the building, other than adjacent concealed spaces within attic or roof spaces, crawl spaces, wall assemblies and ceiling assemblies, by any of the following: (a) one of the finishes described in Subsections 9.29.4. to 9.29.9., (b) provided the building does not contain a Group C major occupancy, sheet metal that, (i) is mechanically fastened to the supporting assembly independent of the insulation, (ii) is not less than 0.38 mm thick, and (iii) has a melting point not less than 650°C, or (c) any thermal barrier that meets the requirements of Sentence 3.1.5.15. (2). (2) A walk-in cooler or freezer consisting of factory-assembled wall, floor or ceiling panels containing foamed plastics is permitted to be used, provided the panels, (a) are protected on both sides by sheet metal not less than 0.38 mm thick having a melting point not less than 650°C, (b) do not contain an air space, and (c) have a flame-spread rating that is not more than that permitted for the room or space in which they are located or that they bound. (3) The flame-spread rating of panels required in Clause (2)(c) shall be determined by subjecting a sample panel with an assembled joint typical of field installation to the applicable test described in Subsection 3.1.12. (4) Thermosetting foamed plastic insulation having a flame-spread rating of not more than 200 is permitted to be used in factory-assembled doors in storage garages serving buildings of residential occupancy provided that, (a) the insulation is covered on the interior with a metallic foil, (b) the assembly has a surface flame-spread rating of not more than 200, and (c) the assembly incorporates no air spaces.

(1) Except as required in Sentence (2), thermal insulation shall conform to the requirements of, (a) ASTM C726, “Mineral Wool Roof Insulation Board,” (b) CAN/CGSB-51.25-M, “Thermal Insulation, Phenolic, Faced”, (c) CGSB 51-GP-27M, “Thermal Insulation, Polystyrene, Loose Fill”, (d) CAN/ULC-S701.1, “Thermal Insulation, Polystyrene Boards”, (e) CAN/ULC-S702 “Mineral Fibre Thermal Insulation for Buildings”, (f) CAN/ULC-S703, “Cellulose Fibre Insulation for Buildings”, (g) CAN/ULC-S704, “Thermal Insulation, Polyurethane and Polyisocyanurate, Boards, Faced”, (h) CAN/ULC-S705.1, “Thermal Insulation - Spray Applied Rigid Polyurethane Foam, Medium Density - Material - Specification”, or (i )CAN/ULC-S706.1, “Wood Fibre Insulating Boards for Buildings”. (2) The flame-spread rating requirements contained in the standards listed in Sentence (1) shall not apply. (3) Insulation in contact with the ground shall be inert to the action of soil and water and be such that its insulative properties are not significantly reduced by moisture. (4) Type 1 expanded polystyrene insulation as described in CAN/ULC-S701, “Thermal Insulation, Polystyrene, Boards and Pipe Covering”, shall not be used as roof insulation applied above the roofing membrane.