Where There’s Smoke, There’s Fire [Rated]
One of the most exciting things about the design and construction industries is that they are never static, always changing and learning and evolving. And one of the most complicated parts of being in these industries is that you have to be too. There is no complacency, no “just knowing” an answer, because the exact second you feel confident in something, the answer has changed and you’re off to research yet another new code or technology or innovation. Interesting? Yes! Educational? Yes! Frustrating? Also sometimes yes!
One such area that seems to be continually fluid and therefore a source of continual confusion is fire and smoke ratings for framing. It is of course vitally important, but it can also be complicated to understand what and where and how certain products can be – and cannot be – used. There is so much to know, and requirements will differ per area and per project, but the following outline can be a reference on your way to finding the right solution for your project.
Fire-Rated Framing and Glazing
If you need to use fire-rated framing on a job, the most important question to first answer is the amount of fire-rating that you actually need. There are many options, which are offered in standardized increments of minutes, and a 20-minute fire-rated frame is going to be much different than a 90-minute frame in terms of the options available.
Rating
The first factor that may be determined by rating required is the framing material itself. Interior commercial framing is often made from aluminum, but aluminum is a soft metal that often cannot offer higher fire-ratings.
So, while you may be able to have a 45-minute rated frame in aluminum, perhaps even from the same manufacturer that is providing the rest of the framing on the job, you probably couldn’t do the same with a 120-minute requirement.
There are, however, manufacturers who make higher rated systems that they then clad in aluminum specifically to allow for aesthetic and finish matching to the remainder of a space.
Material
So if fire-rated systems aren’t all made from aluminum, what metal is used for their construction instead? Steel! Steel systems allow for higher fire-ratings, but they also contribute to fire-rated systems being very heavy – and very expensive.
There are, as well, limitations in both the framing and glazing configurations that can be achieved while maintaining certain ratings, so it’s important to understand these limitations during the design process. Many of these come in the form of maximum glass panel sizes, which necessitates the set up of the framing members.
Fire-rated glazing insulated glass units [IGUs] are also remarkably heavy; something to keep in mind if your project is going to require a stair carry!
Cost and Lead Time
Fire-rated solutions across the industry have long lead times and high costs compared to any other class of interior framing systems.
There are few companies in the United States that have the capability of producing full fire-rated systems; combine that with the high cost of the materials and the exacting requirements for certified ratings – plus the growing need – and it’s no wonder these areas tend to accompany major considerations.
While sometimes using a fire-rated system is unavoidable, it is important to take into account the implications of the cost and lead time as they are fairly unyielding; while there are certain ways to slightly improve results, in general this is one place where there really aren’t options to expedite materials or value engineer significant savings.
Smoke Ratings [and Non-Ratings]
Given the high cost and long lead times mentioned above, it’s no wonder that alternatives are sought in certain situations. Of course, there are areas where you will need to have a certified, fire-rated system. But more and more, requests are also coming in for “smoke-rated” systems. At the same time, it seems like there is an awful lot of confusion regarding what that actually means.
Rating
The first question we usually ask when addressing a question about a smoke-rated system is “Does it actually need to be rated?” While fire-rating requirements are fairly cut and dry about what they must entail, most of the smoke-conscious jobs we’ve worked on have not been actually “rated” at all.
If you do need a real deal, UL, certifiable smoke-rated system, many of the points from the fire-rated section above still stand, including where you can purchase those products. At that point, they are essentially just low grade fire-rated systems, at least from an overall cost and lead time perspective.
But if the goal is to, say, smoke seal an elevator lobby [something we’ve been seeing more and more of lately], then we are often able to offer other solutions that can be utilized without breaking the bank – and waiting 17 weeks to do it.
Smoke Sealing Options
One example of a smoke-sealed condition that we often offer as a solution makes use of our framed Litespace system.
As Litespace always includes a fully-gasketed door frame on all three sides, we just add an automatic door bottom to framed doors as a way to seal the fourth edge and integrate some additional UL rated smoke gasketing to really seal the deal.
Litespace is cost-effective and has a lead time of only three to four weeks for clear and black stocked finishes – a difference of months compared to a truly fire-rated system.
Whether you need the most robust of certified fire-rated products or just a smoke-sealed door or two, let us assist on your next project! Contact Us.
Arch Street Glass is not a code consultant and the above offers only our perspective on fire- and smoke-rated framing based on our experience. Please consult with the relevant professionals regarding specific regulations and requirements for your area.