Fire safety in the residential buildings codes focuses on two product characteristics:
The second characteristic is often described as the amount of time a fire fighter can be in a structure fighting the fire without it falling down. Different types of occupancy have different fire resistance requirements. Most standard single-family residential structures do not have a Fire Resistance requirement for the occupied areas, since getting out of a single family structure during a fire should be obvious and easy to do. Commercial and multi-family structures do have a range of fire resistance requirements ranging from 1-4 hours, depending on occupancy type. In recent testing conducted at Western Fire Center, Inc in Kelso Washington which is an iAS accrediated testing laboratory under the ASTM standard E119 showed that the BamCore wall system achieved the standard 1hr and 2hr fire ratings in conjunction with applied dry wall while maintaining the load of 30,800 pounds. Nearly every product uses applied drywall to achieve these fire resistance ratings.
The first characteristic, Flame Spread, can be thought of as more important for personal safety in single-family residences. It measures how fast the flames spread to engulf the structure, which can impact how quickly someone can safely get out of the burning building. BamCore’s Prime Panels perform uniquely well in standardized fire safety ratings compared to all untreated wood based materials. The primary rating system for building material has three Classes: A, B, and C. The rating is based on a combination of two factors when a product is exposed to blowing flame: how quickly the flames travel along the surface of the material and how much smoke develops while the flames are traveling. In an independent lab test, BamCore’s Prime Panels outperformed all other untreated wood-based materials, including cedar and redwood. Independent lab testing showed that BamCore’s untreated Prime Wall Panels achieve a flame spread rating of only 40, whereas other structural wood products like OSB and T1-11 siding range from 76 to 200. The chart below shows the combined flame spread and smoke generation ratings. Specifically, BamCore’s Prime Wall Panels were the best performing Class B material, recognizing that no untreated wood product-whole or engineered—has a lower flame spread performance. While other products are also used to complete the framing of a building, using BamCore’s Prime Wall System adds a significant safety factor for single-family residential structures.
In addition to structural strength, effective building materials also need to have acceptable behavior when exposed to fire. Fire behavior can be measured in two ways: fire reaction and fire resistance. Fire reaction indicates how easily a material can catch fire and spread the fire. Fire resistance indicates how the material retains its structural strength. BamCore’s fire resistance tests are now pending. Until the tests results are available, the following section provides fire resistance background on the main structural material in BamCore’s panel, Guadua bamboo.
Fire Reaction and Resistance of Guadua Bamboo.
Researchers recently tested the fire behavior of Guadua bamboo, both as a whole culm and as laminated board, and a pine based standard plywood. Relative to fire reaction, their results showed that laminated bamboo lumber is within the standard limits used for structural woods. The chart below shows the interaction between ignition time and heat flux. The longer the ignition time, (the higher on the vertical axis), the better. Or the more heat flux needed to generate the ignition (the further right on the horizontal axis) the better. The curves in the chart show that whole Guadua bamboo is superior to either laminated bamboo or pine plywood. But they also show that laminated bamboo lumber is the same or slightly better than the pine plywood. Relative to fire resistance or the structural integrity that remains during a fire, Guadua culms, and laminated Guadua are both better than plywood. Only at high temperatures, over 200° C, does laminated Guadua underperform the pine plywood. The chart below shows that as the temperature of fire starts to rise (100° and 150° C), the structural integrity of the two Guadua products holds better than that of pine plywood.
Overall, the researchers conclude, “Based on the results of this exploratory research, round and laminated Guadua [bamboo] provided better results than plywood, and most are comparable to those commonly indicated from different wood species.”