As more and more states move to adopt the 2018 IBC, it's important to know about a few code updates that impact the design of occupied roof spaces. And if you're jurisdiction is on the ball and already adopted the 2021 IBC, there are a few additional items that apply to you.

In the last year or so, there have been several fire incidents during the construction of wood-framed residential buildings. Recently, in January 2021, a fire at the Ely at Fort Apache apartment complex in Las Vegas completely destroyed the building, racking up an estimated $25-30 million in damages. Or last year, a Jacksonville, Florida grew so large that it shut down a portion of nearby Interstate 295 and forced the local fire department to deploy 45 apparatus, including 14 engines and seven ladder trucks. In both of these cases, as well as other similar fires, there were two clear similarities:

• The building construction included wood structural members (Type III, IV or V construction)
• The building sprinkler systems were not yet active

In large, wood-framed apartment buildings, the window of time between enclosure of the structure and the building sprinkler system being functional is a clear vulnerability. The presence of a huge fuel load without an active fire sprinkler systems is a dangerous situation, where a single ignition source can lead to horrific fire losses. 

While working in the early phases of a project, a mechanical engineer recently asked for an estimate of the required stair pressurization system fan capacity. On this particular project, I am planning to do a CONTAM analysis, but won't start that portion until later in the Design Development phase.

Since I wanted to give the mechanical engineer an estimate for sizing purposes, I put together a quick calculator to estimate the fan size. Check it out at the link below!