StonePly real stone and aluminum honeycomb panels are inherently flame resistant. Composed of non combustible stone, non combustible aluminum and a very small amount of aviation epoxy adhesive, they are safe. StonePly stone panels have an ASTM E-84 Flame spread index of 0 and a smoke contribution of 5. The "smoke contribution" is primarily water vapor and can vary by stone type. This gives StonePly a Class A per the NFPA standard or Class 1 per the UBC standard.
When the common stone cladding system (1 3/4" to 3" thick slabs or panels of granite or marble with stainless steel anchors) is used for high-rise buildings, the stone wall system can pose a safety hazard if the fire breeches the buildings exterior envelope. While the stone panels will not burn, the unreinforcted stone can shatter or crack when exposed to the intense heat from a fire. This is compounded by thermal shock when firefighters spray cool water on the super heated stone and it shatters. Since the attachment is only at the stone kerfs, the cracked stone can fall from the building and the public and rescue workers can be in danger from the heavy falling stone.
With StonePly, the stone is a thin light weight veneer bonded to the aluminum panel and the panel is then mechanically fastened to the structure. The entire panel weighs just 15% of the weight of common stone slabs and is classified as a light weight cladding. When tested, under prolonged exposure to intense flame and heat the stone bond endures and the stone flakes away only as small stone chips.
Please contact us with any StonePly stone cladding questions. We are here to help. Unique applications or unusual criteria should be reviewed by a professional engineer.