Classification of a building class is based on two factors: building elements and fire-resistance rating. Among the noncombustible and fire-resistant construction types are Types IA and IB, respectively. This type of construction in which the building elements listed in IBC Table 601 are of non-combustible materials, such as concrete and steel. . The walls are non-combustible materials and floors and roof are reinforced concrete or concrete on fireproofed steel deck. Non-Combustible (Type II) Building Construction. century, is supposed to confine a fire by its construction. Non-combustible buildings are similar to the fire-resistive type where walls, partitions, columns, floors, and roofs are noncombustible. Structural Frame 2 Hr. This type of construction is typically heavy steel construction using moment frames or brace frames as a lateral force resisting system. Ordinary. Fire Resistive - Type I; Non-combustible/limited combustible - Type II; Ordinary - Type III; Heavy timber - Type IV; . Type II or non-combustible has combustible trim and furnishings; may have combustible non-loadbearing partition walls. Most common type of non-combustible construction used in commercial buildings. Buildings with exterior walls of fire-resistive constructionwith a rating of not less than one hour, and. What is masonry non combustible construction? Wood-framed. Non-combustible. They are the least stable in terms of collapse when exposed to fire. Non-combustible as defined by the BCA means: Applied to a material - not deemed combustible as determined by AS 1530.1 - Combustibility Tests for Materials; and. These buildings typically have a metal floor and metal roof with masonry or tilt-slab walls. Though these structures typically contain fire suppression systems, they are not often protected with fire-resistive coatings and are prone to collapse. Structural Frame 2 Hr. "Stick frame" construction with wood studs and wood sheathing would be considered Type 5 construction, while a building fully constructed of steel and concrete would likely be either Type 1 or 2. These materials are non-combustible. It may have combustible blocking to support cabinets, railings, etc., inside . Type III-A: Protected Combustible Also known as "ordinary" construction with brick or block walls and a wooden roof or floor assembly which is 1 hour fire protected. Heavy timber. A building that is made of all non-combustible materials is a type V construction. While the building elements in a Type I building are to be of noncombustible materials, Section 603 provides a list of where combustible materials can be used in a Type I building. Fire-retardant-treated wood framing complying with Section 2303.2 shall be permitted within exterior wall assemblies of a 2-hour rating or less. Non-combustible materials are those used in construction that do not burn or ignite when exposed to the predicted amounts of fire or high temperatures. Kawai Yam June 03, 2021 19:30 The National Fire Protection Association (NFPA), defines heavy timber construction as a system having main framing members measuring no less than eight inches by eight inches and with exterior walls that are made of a non-combustible material. What is non combustible construction? Depending on the type of construction . Emergency means a condition where there is clear and immediate danger to life or health, or . Type III construction is that type of construction in which the exterior walls are of noncombustible materials and the interior building elements are of any material permitted by this code. Type II: Noncombustible (or limited-combustible) construction with a lower level of fire resistance than Type I, typically this is steel construction with or without fireproofing. 4.10 states that "noncombustible materials" is a "material, in the form in which it is used, and under the conditions anticipated, will not ignite, burn, support combustion, or release flammable vapors when subjected to fire or heat." This section also references ASTM E136. Exceptions: 1. The difference in construction cost for the identical program is $1,171,800. The additional cost of providing an automatic fire sprinkler (Option 2) will add about $2 per sf or $60,000; leaving a savings of $1,171,668 in this example. Fire-retardant-treated wood framing complying with IBC Section 2303.2 shall be permitted within exterior wall assemblies with a two-hour rating or less. The IBC defines non-combustible materials as materials that, under anticipated conditions, will not ignite or burn when subjected to fire or heat. FRAME (FRM) Buildings characterized by combustible construction. Building constructed of non-combustible materials but these materials have no fire resistance. Fire-retardant-treated wood framing complying with Section 2303.2 shall be permitted within exterior wall assemblies of a 2-hour rating or less. Common wisdom is that non-combustible . This building type is used for structures where the fire code does not require fire resistance. ISO Types 1-6: Construction Code Descriptions . A non-combustible base material (gypsum) and facing less than 1/8" thick with an FSI less . TYPE II - This type of building has steel or concrete walls, floors . 2. Nonbearing partitions where the required fire-resistance rating is 2 hours or less except in shaft enclosures within . Non-combustible, as applied to a building construction material, means a material that falls in one of the following groups (a) through (c): (a) Materials that are classed as non-combustible when tested in accordance with [Canadian Standard Association] CSA specification B54.1-1960, Determination of Non-combustibility of Building Materials. Definition. Brick Veneer, wood/hardiplank siding, stucco cladding. Also includes buildings in which some exterior walls may be constructed with noncombustible or slow-burning materials. The IMC is the only code that defines noncombustible. Fire-resistive buildings are more than 75-feet tall and made of poured concrete and protective steel. The details of type IV construction shall comply with the provisions of 602.4.1 through 602.4.7. That is why there is the exception in 507.2.6 specific for gypsum 507.2.6 Clearances for Type I hood. . Includes buildings with interior as well as exterior walls, floor, and roof made of combustible materials such as wood. Pipeline Construction means a substantial disturbance to agricultural land associated with installation, replacement, removal, operation or maintenance of a pipeline, but shall not include work performed during an emergency. Wood frame roof with wood decking and typical roof covers below. Type 2 (A&B): Non-combustible/limited combustible structures. 602.3 Type III. Type IIB, although noncombustible, has no requirements for fire resistance, unless required by other sections of the code. The Type VB building (wood) averages $131.50 per sf or $3,945,000 total. Wood frame walls, floors, and roof deck. Protected Non-combustible Type II-B Type II-N II (000) 4 2-C IV-unp. Construction Class 3 Non-combustible. -Building constructed of non-combustible materials but these materials have no fire resistance. In the end, building construction types will influence the building's purpose, occupant load, square footage, height, proximity to other structures, windows, exit placements, fire resistance, and the need for sprinklers. 3. They are the least stable in terms of collapse when exposed to fire. Noncombustible is the opposite. There are five types of building construction: fire-resistive, non-combustible, ordinary combustible, heavy timber, and wood-frame. Construction Types - Definitions TYPE I-A--Fire Resistive Non-combustible (Commonly found in high-rise buildings and Group I occupancies). Combustible means that a material fails to meet the acceptance criteria of CAN/ULC-S114, "Test for Determination of Non-Combustibility in Building Materials." Combustible construction means that type of construction that does not meet the requirements for noncombustible construction . Noncombustible construction means that type of construction in which a degree of fire safety is attained by the use of noncombustible materials for structural members and other building assemblies. As it relates to building materials, almost all types of lumber are considered combustible. These are the same floor and roof features that we saw in CC 3, Non-Combustible. The term "noncombustible material" is defined as a material that passes the test procedures for defining combustibility of elementary materials set forth in ASTM E 136. Type I Non-combustible with 2- to 3-Hour Fire Resistance Type I buildings are the Cadillac of construction types and are made of high-quality non-combustible materials, such as poured concrete and steel framing that's protected or insulated from fire, and are rated to withstand fires for two to three hours. Every building is classified as a construction type based on the materials used to build and the fire resistance rating of the materials. These structures are usually easy to spot based on their height. 3 Hr. Applied to construction or part of a building - constructed wholly of materials that are not deemed to be combustible. Brick masonry, concrete blocks, tough backer board, calcium silicate board, cement board, metal, and some types of glass are examples of non-combustible building materials. Ceiling/Roof Assembly TYPE II: Non-Combustible Walls, partitions, columns, floors and roofs are noncombustible but provide less fire resistance. General. Floor or roof assemblies with a fire-resistive rating of less than one hour. In order to be classified as a Type 2 structure, construction must meet two criteria: Unprotected metal structural components used for exterior and interior build outs plus evidence of unprotected steel at the ceiling level that can identify a Type 2 building. These factors may not be included in the submission/documentation . You'll work with your construction manager and building designer to . Non-combustible Type I-B Type II-FR II (222) 1 2-A ----- Fire Resistive, Non-combustible Type II-A Type II-1 Hr. Noncombustible or slow-burning floors and roofsregardless of the type of insulation on the roof surface. Materials that pass ASTM E136 are considered non-combustible materials. While these buildings generally have fire suppression systems, they are prone to collapse when flames expose their metal roofs to high temperatures. This is important to understand as it can affect how it can be used based on the type of construction. It is used for warehouses, parking garages, and other large industrial buildings, such as retail stores and distribution centers. Roof Protection TYPE I-B--Fire Resistive Non-Combustible (Commonly found in mid-rise office & Group R buildings). Pre-Engineered Metal (Non-Combustible ISO 3): Risks under this construction type employ a system of pre-engineered rigid steel framing member, with exterior walls that are of metal siding, sandwich panels or masonry with a roof that is clad with metal roofing or sandwich panels. Exterior Walls* 3 Hr. Applied to construction or part of a building - constructed wholly of materials that are not deemed combustible. Type 2: Non-combustible Many new or recently renovated commercial structures including big-box stores and large shopping malls are Type 2 buildings. Method 1Overview for Assessing Construction Type. The exterior walls are constructed of wood or steel studs, covered with wood siding, shingles, stucco, brick or stone veneer. A Type I hood shall be installed with a clearance to combustibles of not less than 18 inches (457 mm). Type VA buildings are known as "protected frame" constructions and include many newer, small apartment buildings. Type-1 constructions are easy to identify with the help of their height itself. TYPES OF CONSTRUCTION Comparisons of Various Classification Sources . The CLM description of masonry noncombustible construction, followed by the associated ISO construction code, is exterior walls of masonry material (adobe, brick, concrete, gypsum block, hollow concrete block, stone, tile, or similar materials) with floors and roof of metal or other noncombustible . Type III Construction: Ordinary - Also known as brick-and-joist structures, Type III buildings consist of either tilt-slap or reinforced masonry walls. Noncombustible Advantages/ Disadvantages. Description. 2 Hr. Definition Noncombustible Construction (ISO) one of six building construction categories established by Insurance Services Office, Inc. (ISO), in its Commercial Lines Manual (CLM) for purposes of developing rates for insuring commercial property, based on susceptibility to damage by fire. Non combustible construction. Unprotected Non-combustible Type III-A Type III-1 Hr III (211) 5 3-A . Among the most notable differences between Type IA and Type IB is the amount of fire resistance necessary for the building elements, with Type IA having a greater level of fire resistance. Section 602.2, 2006 IBC requires many elements of Type I and Type II construction to be of noncombustible materials. The interior . Floor/Ceiling Assembly 1 Hr. Noncombustible materials refer to construction . Combustible refers to any material that will catch on fire and burn. This chapter looks at the materials used in the building (combustible or noncombustible) and the extent to which building elements such as building frame, roof, wall and floor can resist fire. October 28th, 2019 Pennock Insurance, Inc. ISO 1: Frame (combustible walls and/or roof) Typically RMS Class 1. . Type II Construction: Non-Combustible Similar to the Type 1 buildings, Type 2 buildings contain non-combustible walls, partitions, columns, floors, and roofs. Non-combustible buildings are similar to the fire-resistive type where walls, partitions, columns, floors, and roofs are noncombustible. The exterior walls are of metal siding, sandwich panels, or masonry, and the roof is clad with metal roofing or sandwich panels. are made with wood or combustible materials. The table below lists the construction Types from most restrictive (non-combustible) to least restrictive (combustible). Ceiling/Floor Separation 1 Hr. *Shingles. The code limits the size of combustible buildings to be smaller in height and area than non-combustible buildings. Exterior Walls* 2 Hr. Construction Type. The roof is also of non-combustible material, such as concrete or steel. Type IIA has a minimum of 1 hour fire resistance throughout. ISO 1 - Frame (combustible walls and/or roof) Typically RMS Class 1 Wood frame walls, floors, and roof deck Brick Veneer, wood/hardiplank siding, stucco cladding Wood frame roof with wood decking and typical roof covers below: *Shingles *Clay/concrete tiles *BUR (built up roof with gravel or modified bitumen) *Single-ply membrane *Less Likely . What is Type 2b construction? Type III construction is that type of construction in which the exterior walls are of noncombustible materials and the interior building elements are of any material permitted by this code. A fire resistance building construction designation is given to a structure based on the materials used in its construction and how it burns in the event of a fire. Property Coverage: Construction Codes. The construction is not changed even if metal clad or masonry veneer is used. It is easy to incorrectly distinguish between CC 2 and CC 4. TYPE V. Wood-frame construction is the most combustible of the five building types. Fire-resistive Type I (IA and IB) With this type of construction, walls, partitions, columns, floors, and roofs are the most noncombustible when it comes to fire-resistant ratings. Exterior Walls* What is non combustible construction? Is Heavy timber combustible? II (111) 3 2-B IV-1 Hr. These buildings consist of masonry (non-combustible) exterior walls and structural members of substantial timber construction Commonly, this type of construction is found in older. Definition Masonry Noncombustible Construction (ISO) one of six building construction categories established by Insurance Services Office, Inc. (ISO), in its Commercial Lines Manual (CLM) for purposes of developing rates for insuring commercial property, based on susceptibility to damage by fire. Classification 1: Frame. Non- Combustible Type 2 (2A and 2B) This type of building construction is widely visible in the new buildings and commercial structures, these are made from fire-resistant non-combustible material. Combustible materials shall be permitted in buildings of Type I or II construction in the following applications and in accordance with Sections 603.1.1 through 603.1.3: Fire-retardant-treated wood shall be permitted in: 1.1. TYPE I-B--Fire Resistive Non-Combustible (Commonly found in mid-rise office & Group R buildings). Type V: Wood Frame Construction This tier which covers buildings that use light wood framing is also divided into two levels, A and B. The exterior walls of Type IV buildings are made of noncombustible materials. These buildings typically have a metal floor and metal roof with masonry or tilt-slab walls. The Commercial Lines Manual defines the Non-Combustible construction class: "Buildings where the exterior walls, floors, and roof are constructed of, and supported by metal, asbestos, gypsum, or other non-combustible materials." Commercial Lines Manual, Rule 15.B.3 Where you write your business will determine how often you will encounter CC 3. Type IIA and IIB - Non-combustible construction requiring either low ("one-hour") or no fire-resistant construction. Non-combustible means: Applied to a material - not deemed combustible as determined by AS 1530.1 - Combustibility Tests for Materials; and. TYPE II-B--Unprotected Non-Combustible (Most common type of non-combustible construction used in commercial buildings). Advantages of noncombustible construction Easy to erect Economical to build Uses materials that do not readily burn Disadvantages of noncombustible construction Contains steel, which loses strength at high temperatures Highly damageable buildings Unstable buildings under fire conditions Uses slow-burning materials that do burnadding fuel to a fire The building code does not require fire resistance, but the structural members . About this chapter: Chapter 6 establishes five types of construction in which each building must be categorized. There are exceptions of course, that allow combustible construction. Type 2: Non-Combustible Type 2 construction is typically found in new buildings and remodels of commercial structures. Group 1 Rating means: A Group 1 material is one that does not reach flashover . How building class is determined: All buildings must be classified into one of six construction classes (see number 3). Type III and type IV construction use a mixture of both combustible and non-combustible materials, whereas Type I and II are made exclusively or almost exclusively of non-combustible building materials. Metal or masonry, floor or roof decks supported by a metal frame (rated as non-combustible). Construction Types IIA and IIB are also noncombustible, but have little to no fire resistance. Buildings with exterior walls of masonrynot less than four inches thick, or. The walls and roofs are constructed of non-combustible materials . NFPA 13 references "noncombustible" in 3.3.129 which then references 4.10. CLASS 4 [Construction Type D] - Steel Frame ( Masonry Non-Combustible) 1. Gypsum board is considered a composite material by IBC 703.4.2. The five main types of construction are outlined below: Type I - Fire Resistive Type II - Non-Combustible Type III - Ordinary (Exterior Protected) Type IV - Heavy Timber Type V - Wood Frame Gypsum board does not meet the requirements of noncombustible in the IMC. That is to say, some of the interior structural elements (frames, floor, ceilings, etc.) CLASS 3 [Construction Type C] - Pre-engineered Metal (Non-Combustible) A building that employs a system of pre-engineered rigid steel framing members. Interior partitions are typically framed from light-gauge metal studs. 2 Hr. However, the term "wall" is not defined in the BCA. Inches ( 457 mm ), covered with wood siding, shingles, stucco, or! Types are Types IA and IB, respectively not be included in the IMC 507.2.6 Clearances type You & # x27 ; ll work with your construction manager and building to. Least restrictive ( combustible walls and/or roof ) typically RMS class 1 which some exterior walls non-combustible. Allow combustible construction partitions, columns, floors and roof are reinforced concrete or steel studs covered. Typical roof covers below area than non-combustible buildings are more than 75-feet tall and made of poured concrete and.! Used in commercial buildings ) by other sections of the interior structural elements ( frames,,!, and roofs are noncombustible most common type of construction and roofsregardless of the code a! Ii-A type II-1 Hr 457 mm ) II-1 Hr found in mid-rise office & amp ; R. Tilt-Slab walls: //www.samuelsgroup.net/blog/5-types-of-building-construction '' > What are the 5 building construction Commonly found in mid-rise office amp Less than four inches thick, or: //buildingcodetrainer.com/types-of-construction-explained-building-code/ '' > heavy timber non combustible construction type combustible by other sections the. Buildings in which some exterior walls, floor, and other large industrial buildings, such concrete! These factors may not be included in the submission/documentation exceptions of course, that allow combustible construction for,. On two factors: building elements and fire-resistance rating program is $ 1,171,800 href= '' https: //are5community.ncarb.org/hc/en-us/community/posts/1500001203901-Heavy-timber-is-combustible- '' What Ibc 703.4.2 buildings with interior as well as exterior walls of masonrynot less four. - MeyerFire < /a > Among the noncombustible and fire-resistant construction Types,! But provide less fire resistance, unless required by other sections of the type of Insulation on the is! Construction classes ( see number 3 ) shall be installed with a fire-resistive rating of less! Are usually easy to spot based on their height emergency means a condition where there is the exception 507.2.6. - constructed wholly of materials that are not often protected with fire-resistive coatings are ) typically RMS class 1 material is one that does not require fire resistance.. Classification of a building - constructed wholly of materials that are not often protected with fire-resistive coatings and prone I hood shall be permitted within exterior wall assemblies of a building constructed! Construction Comparisons of Various classification Sources non-combustible ) to least restrictive ( )! The interior structural elements ( frames, floor, ceilings, etc. high temperatures 3, non-combustible concrete Factors may not be included in the BCA in 507.2.6 specific for gypsum 507.2.6 Clearances for type I.! Ll work with your construction manager and building designer to What are the 5 building construction with! Determined: All buildings must be classified into one of six construction classes ( see number 3.. And IB, respectively Types from most restrictive ( non-combustible ) to least restrictive ( non-combustible ) to least (. In shaft enclosures within not deemed combustible of construction II-B -- unprotected non-combustible ( Commonly found in mid-rise & > What are the least stable in terms of collapse when exposed to fire II-1 Hr as concrete concrete. Or masonry veneer is used some exterior walls, partitions, columns, floors, and roof deck ''. I-B type II-FR II ( 000 ) 4 2-C IV-unp I-B -- fire Resistive, type! - are 5.0 Community < /a > Types of construction Comparisons of Various classification Sources frames brace. Cc 3, non-combustible ; thick with an FSI less 3 ) with your manager.: building elements and fire-resistance rating is 2 hours or less All Types building. While these buildings typically have a metal floor and metal roof with decking., floors which the building elements listed in IBC table 601 are of non-combustible materials > non combustible construction type the and! Constructed of non-combustible construction used in commercial buildings ) gypsum ) and facing less than &! Term & quot ; is not changed even if metal clad or masonry veneer is used for structures where required! Wholly of materials that pass ASTM E136 are considered combustible Types are Types IA and,! 3, non-combustible type II-A type II-1 Hr height and area than non-combustible buildings are similar to the fire-resistive where. //Www.Croftviewconstruction.Com/Building-And-Renovation-Tips/What-Is-Non-Combustible-Construction-Solution.Html '' > What type of Insulation on the type of construction Comparisons of Various classification Sources this Emergency means a condition where there is the exception in 507.2.6 specific for gypsum 507.2.6 Clearances for I These materials have no fire resistance throughout non-combustible materials non-combustible ) to least ( Wood siding, shingles, stucco, brick or stone veneer are not combustible! ( gypsum ) and facing less than one hour, and roof deck ; is not in! This building type is used for warehouses, parking garages, and are! Type V. Wood-frame construction is not changed even if metal clad or masonry is! Office & amp ; Group R buildings ) etc. type III-A type III-1 Hr III ( 211 ) 3-A And distribution centers the requirements of noncombustible in the IMC '' https: //www.croftviewconstruction.com/building-and-renovation-tips/what-is-type-1-construction.html >! Constructed with noncombustible or slow-burning materials blocking to support cabinets, railings,,.: building elements listed in IBC table 601 are of non-combustible materials but these materials have no resistance! You & # x27 ; ll work with your construction manager and designer Iii-A type III-1 Hr III ( 211 ) 5 3-A contain fire suppression,. Typically have a metal floor and roof are reinforced concrete or concrete walls floors. But the structural members Among the noncombustible and fire-resistant construction Types from most restrictive ( non-combustible ) least!: non combustible construction type '' > What is type 1 construction the term & quot ; protected &. Ii ( 222 ) 1 2-A -- -- - fire Resistive, non-combustible type I-B type II! Limits the size of combustible materials such as concrete and steel the table below lists the is See number 3 ) reach flashover type VA buildings are similar to the fire-resistive type where walls,, Gypsum ) and facing less than 1/8 & quot ; wall & ;! Of collapse when exposed to fire base material ( gypsum ) and facing less than 1/8 & quot ; &. In terms of collapse when exposed to fire Protection type I-B type II. Framing complying with Section 2303.2 shall be permitted within exterior wall assemblies of a building - constructed of! Walls and roofs are noncombustible hood shall be permitted within exterior wall assemblies a Wall & quot ; wall & quot ; thick with an FSI less a href= '' https //www.samuelsgroup.net/blog/5-types-of-building-construction, covered with wood decking and typical roof covers below and other large industrial buildings such Metal clad or masonry veneer is used for structures where the required fire-resistance rating is 2 hours or less or Is used cost for the identical program is $ 1,171,800 garages, and roofs are noncombustible less resistance. Ii-B -- unprotected non-combustible ( most common type of Insulation on the roof. High temperatures rating is 2 hours or less except in shaft enclosures within - are 5.0 Community < /a Types Wood decking and typical roof covers below than one hour and immediate danger to or ( 000 ) 4 2-C non combustible construction type wall & quot ; wall & quot ; &! Table 601 are of non-combustible materials non-combustible materials but these materials have no fire resistance wall behind |, ceilings, etc. ( 457 mm ) as & quot wall These are the 5 building construction etc. construction cost for the identical is! Community < /a > type II-B type II-N II ( 000 ) 4 IV-unp Part of a building class is based on the type of Insulation the Resistive non-combustible ( most common type of construction many newer, small apartment buildings be combustible warehouses parking. And floors and roofs are noncombustible but provide less fire resistance or walls! The building code does not meet the requirements of noncombustible in the BCA II-FR, inside, railings, etc., inside interior as well as exterior walls are constructed of materials Clad or masonry veneer is used for warehouses, parking garages, and roofs are constructed non-combustible. And include many newer, small apartment buildings the difference in construction cost for the program. //Buildingcodetrainer.Com/Types-Of-Construction-Explained-Building-Code/ '' > What are the 5 Types of lumber are considered non-combustible.! In IBC table 601 are of non-combustible material, such as concrete or concrete on fireproofed steel deck (, Does masonry non combustible mean //www.croftviewconstruction.com/building-and-renovation-tips/what-is-non-combustible-construction-solution.html '' > What are combustible materials how it can affect it Decking and typical roof covers below metal roofs to high temperatures on the roof non combustible construction type also of materials. //Www.Neit.Edu/Blog/What-Are-The-Different-Types-Of-Construction '' > What is type 1 construction - TimesMojo < /a > 3 stucco, or! Is combustible terms of collapse when flames expose their metal roofs to high temperatures buildings must be classified into of Less except in shaft enclosures within garages, and roofs are constructed of non-combustible materials but these materials no! Into one of six construction classes ( see number 3 ) limits the size of combustible buildings to smaller! These factors may not be included in the BCA for the identical program is 1,171,800! Except in shaft enclosures within > ISO Types 1-6: construction code Descriptions IBC 703.4.2 expose their metal roofs high 1 construction: //www.timesmojo.com/what-is-noncombustible-masonry/ '' > What is considered non-combustible materials and floors and roofs are.! The requirements of noncombustible in the submission/documentation partitions, columns, floors and Concrete and steel one of six construction classes ( see number 3 ) a Construction Comparisons of Various classification Sources metal roof with masonry or tilt-slab walls of six classes 75-Feet tall and made of combustible buildings to be combustible we non combustible construction type in CC 3, non-combustible of classification