Windows for Fire-Prone Areas
Question:
Hi Glass Detective,
I am remodeling a bathroom. The remodel will include a 24 inch wide by 10 inch high slider window. The fixed and slider portions will be dual glass pane panels (double glazed). The base of this window will be 6.5 feet off the bathroom floor. We live in a very high Fire Hazard Severity Zone and this window faces the forest. I was thinking tempered glass would be better than laminated glass because the former sounds as if it would be better able to withstand heat from a forest fire than laminated glass. And if it does break, tempered glass would be more likely to stay in place than laminated glass. Am I correct in thinking the above?
Thank you,
Michael K.
Redding, CA
Answer:
Michael,
Thank you for making contact with the Glass Detective regarding your concerns over selecting the right glass for your bathroom remodeling project. Your primary concern is for glass that can withstand high levels of heat because you live in an area where forest fires are a concern.
For this application, there are ceramic and treated glass products that are used in fireplaces and other types of furnace type applications that certainly could be a good choice. These are called fire-rated or fire-resistant glazing. However, if a fire gets hot enough, it won’t matter what glass you are using because the framing that is holding it in place would either burn or melt. Hopefully you aren’t planning to stay in the room (or home) if the fire is nearby.
I think the quick answer you are looking for is to use tempered glass for the application you describe. It may handle heat levels up to 1,000 degrees Fahrenheit. It can also be fabricated into insulated units and is a safety glass product which is appropriate for your use in a bathroom window. For a higher level of protection there is also excellent fire-rated and fire-resistant glass available.
I am also going to suggest that you read Glass.com’s summary on the differences between tempered and laminated glass because you also mentioned laminated glass as a possibility. From your statements, I think this blog may be of some benefit to you. Laminated glass actually holds in place better than tempered glass due to the polyvinyl interlayer. Thank you again for contacting the Glass.com Detective with your questions and I hope this information is of some value to you.