Due to the growth of technology and the architectural world, construction materials and projects are growing day by day. There are various cladding materials that manufacturers provide for the industry, which are combustible and non-combustible. National Building Code and standards intended to limit the usage and contribution of flammable cladding materials in non-combustible cladding materials for construction. There are various mechanisms and systems to achieve the required safety.
Utilization of Non-Combustible Cladding Materials
Utilization of non-combustible cladding materials such as aluminum composite panels and pre-formed steel panels, and many reinforced building materials do not contribute a significant amount of fuel to fire if supported by inflammable systems. With the current energy performance requirements, various insulation systems can be applied to reduce heat losses through the wall assembly, invoking other code requirements.
The contribution of foam plastics that are practical for insulating the cladding systems is less significant in the context of combustible buildings. In contrast, in non-combustible building materials, the fuel used in the construction can considerably impact the performance of the walls, roofing, and ceilings. Consequently, the standard and regulation requirements are more difficult in the safety of modern buildings.
Non-Combustible Composite Cladding Materials
Where a composite panel such as ACM panels is used for the building cladding systems, the combustibility can increase due to the augmentation of insulation in these sandwiched panel structures. In such cases, each element has to assess for flammability. However, modern building materials suppliers and manufacturers produce aluminum composite panels that feature fire-retardant core substances.
Some fire-retardant-treated wood materials have composite structures with a higher heat release rate of 40 to 50 MJ/m2 than the criteria set out in standard codes and significantly higher than most substance-insulated ACM panels. Additionally, the flame spread indicator of many tested composite panels is zero compared to FRTW, which has a flame spread of 25.
Several modern building materials manufacturers have successfully subjected their claddings to the CAN/ULC s134 testing. These systems are designed for usage in non-combustible construction but can be utilized for flammable structures and will not affect the functionality and practicality of the cladding assembly. These systems consist of a double-wall building with insulated cavity walls for energy efficiency. The division requires a rating, and they are provided by one more layer of gypsum wall panels on the interior side.
Usage of Combustible Claddings in Non-Combustible Construction
Owing to the vertical installation of metal cladding systems, higher than expected vertical fire spread can occur that would be expected if the same substance were installed in the horizontal direction. EIFS, which stands for External Insulation Finish System, is a lightweight synthetic wall cladding system that includes plastic sealing and thin coatings. Thus, the metal cladding requirements of regulations reflect criteria developed for testing EIFS systems set out in the CAN/ULC s-134 testings. The standard tests intend to be indicators of large-scale fire behavior. These tests are not easy to pass without some input from flame testing specialists. One of the tests that are easier to pass than s-134 in Canada is NFPA. Significantly various designs can emerge due to the location of the examination area and the weather on the day of the particular test.
Foamed Plastic in the Building Facade
There are a series of requirements under particular codes that set out criteria for protecting foamed plastic building facades. However, assemblies that comply with s-134 testing do not require to follow the required set out in other codes. It is essential to note that fire blocks are required in wall non-combustible cladding materials. Fire blocks are generally placed in concealed spaces. Essentially, these systems exist every 20m horizontally unless the insulation is non-combustible or has a flame spread rate under 25. Additionally, they should have a vertical fire stopping every 10m. There should be only one gap in areas with air space, and the maximum depth must be 25mm.
Non-Combustible Cladding Materials for Exterior Requirements
In most cases, except for sprinkled constructions over 18m, a thermal barrier of 12.7 is needed. Adjacent areas in metal cladding assemblies are exempted. For buildings over 18m, the panel has to be taped or filled due to the potential smoke spread. Interior walls and ceiling installation in such facilities have thermal protection, which is increased to 15.9mm barriers. Wall cladding materials that are assembled in the factory come separately.
