The year 2022 has only just begun but there is already a trend appearing in the North American construction market towards the use of non-combustible cladding. There have been rumblings about the need for non-combustible cladding for certain construction projects for several years and State and Local Building Codes are now being updated to include this as a requirement.
When it comes to choosing non-combustible cladding, an understanding of the compliancy of each product is required for specification. To help, we have put together this quick guide for our engineered metal non-combustible cladding solution, VitrabondG2®.
Firstly, here’s a quick overview of VitrabondG2®. It has been available globally since 2015 and in North America since 2017 when Fairview Architectural saw that the construction market would soon require non-combustible cladding for some types of construction, a movement seen in other countries around the world. VitrabondG2® was developed specifically to provide all the benefits of aluminum cladding material with the added benefit of being non-combustible.
This innovative product has many advantages and here are just a few reasons why we think you should consider it for your next project should you require a non-combustible cladding solution:
- Non-combustibility – VitrabondG2® is a 4mm aluminum panel classed as non-combustible according to the IBC. Non combustibility is determined by completing two important tests, ASTM E136 and ASTM E84. The common full scale wall assembly fire test NFPA285 is to determine the suitability of using combustible products in non-combustible wall assemblies. Therefore, VitrabondG2® does not require NFPA285 testing when used with other non-combustible products.
- Lightweight – VitrabondG2® weighs just over 0.9 lbs/sf, making it almost half the weight of traditional 3mm(1/8”) solid aluminum plate, and about 60% of the weight of standard fire-rated aluminum composite material. Despite its lightweight, VitrabondG2® is more rigid than both 3mm(1/8” solid aluminum and standard 4mm aluminum composite material, giving it one of the highest strength to weight ratios of any cladding material.
- Cost-effective – thanks to its lighter weight VitrabondG2® is easier to handle and install which will provide major time and cost savings to your construction project both in labor and in the structural components required in the wall assembly.
- Appearance – VitrabondG2® is visually identical to traditional metal composite material but none of the mineral core fillers that are often found in other non-combustible and fire-rated alternatives. It is also available in all the same colors and finishes.
As part of our non-combustible product range, we also have 3mm pre-finished solid aluminum Vitraplate. Find out more about Vitraplate here.
Does VitrabondG2® need to be tested to NFPA285?
The short answer is “not yet”. The NFPA285 is a full-scale fire test for wall assemblies containing combustible materials. The purpose of the NFPA285 is to allow combustible components to be used, as long as the combination of components in the wall assembly does not propagate a fire. According to the International Building Code (IBC) at the time of writing this, VitrabondG2 is a non-combustible building product. The coating and bonding layers are classified as “minor combustible components”, and therefore if there are no combustible components in the wall assembly there is no need to test. Simply put, why fire test a wall assembly that is made up of non-combustible products?
Changes to the IBC are coming however that will require wall assemblies containing non-combustible products such as VitrabondG2® and mineral wool to be tested to NFPA285. This change is to close any loopholes which might allow products such as honeycomb panels, which are embedded in highly flammable glues, to call themselves “non-combustible”. So, while it might seem unnecessary for non-combustible products such as VitrabondG2® and mineral wool insulation to have to be tested to NFPA285, it is a worthwhile preventative measure to ensure our buildings in USA are built safely.
Until these changes take effect, if a wall assembly needs to be tested to NFPA285 then we recommend using our VitrabondFR, a fire-resistant product for use in combustible wall assemblies that must be tested to NFPA285. VitrabondG2® is a state-of-the-art technology advancement on painted aluminum and as such is not intended to replace standard aluminum composite material where fire-resistant products are acceptable for use. After the 20
Can VitrabondG2® be tested to ASTM E-136 to prove it is non-combustible?
The building code has two types of materials.
- Elementary materials
A piece of aluminum is an elementary material and can therefore go through the ASTM E-136 test. If, however, you apply a coating of paint onto the aluminum, it can no longer be put into the furnace, because it is now considered a composite. To overcome this, the building code makes allowance for these minor combustible components that make up a small portion of the end product. If you ask a lab to test aluminum with paint on it, they will only test it if you sign a waiver that includes the cost of repairing their furnace. The paint is flammable, the test will fail, and the furnace will need to be repaired. So even painted solid aluminum cladding cannot be tested for non-combustibility. Instead, the aluminum itself as the primary element must be tested, and together with the minor combustible components such as paint and bonding layers it makes up a composite. Thick layers of glue as found in honeycomb panels cannot and should not be considered minor. And in case you hadn’t realized by now, VitrabondG2® is not a honeycomb panel.