I'm looking for advice on ensuring my battery backup room meets the required two-hour fire resistance. The walls seem manageable with two layers of Gypsum X, but the ceiling is more complicated. I've come across varying requirements suggesting up to four layers of gypsum. Does anyone have a better or simpler solution? This room is in my house's utility space where the batteries will be located.
3 Answers
For the ceiling, the reason for multiple layers of insulation is that heat rises. A wooden frame can catch fire if it gets too hot. Using steel studs can reduce the need for extra insulation layers. You might also want to consider a fire suppression system, like CO2, which removes oxygen from the room when it hits a certain temperature. Just be careful about battery types, as lithium batteries have their own oxygen source.
I didn't find any strict ceiling requirements, just the general two hours of fire resistance. I simply added an extra layer of X over my existing drywall. Interestingly, the codes have a lot of gray areas; for example, my wall needs to be rated for two hours but has to be a floating wall with a gap above the floor. Plus, you won’t find a two-hour rated interior door; a 15-minute one suffices. If you’re concerned about ventilation, modern batteries generally don’t off-gas much.
Usually, there's some coding around fire resistance for these situations, especially in residential settings. People often install battery systems in garages mounted directly on the wall without additional fire-proofing. Keep in mind lithium batteries like Lifepo4 don’t typically catch fire easily, but it's important to ensure they’re in good, insulated cases to avoid overheating.