Is Egress Analysis Impacted during Your Incremental Build Projects?
Travel distance and means of egress have become increasingly popular concerns. As owners expand buildings, they often increase the distance to the nearest exit to the point of violating code requirements. We recently consulted on a project of this type for a car manufacturer.
The manufacturer planned the renovation of an old facility, intending to construct a substantially larger addition, while keeping the functionality of their old space. The addition posed a unique challenge because some exits that were previously serviceable would be blocked by the construction zone. Fewer exit-routes meant that occupants would need to travel greater distances to exit the building. Additionally, when particular exit routes are blocked, the common path of travel must also be considered. Occupants must be given an optional exit route at regular distance intervals. This allows them to circumvent any fire hazards obstructing the main route. We designed a sequence of creative routing solutions that would give people safe escape routes during each construction phase.
Furthermore, once the addition was completed, the new travel distance to reach the exterior of the building was in excess of the prescriptive limitations permitted by the building and fire codes. An engineering analysis and smoke model was required to show that even with increased travel distances, occupants would remain safe from the effects of a fire and smoke during egress from the building.
Incremental builds are often selected by owners as a way to keep buildings functional during the construction process. In the case of additions or renovation projects, part of the building will be closed off for work. All other segments will be available for use during this project phase. Upon segment completion, a new area will be rendered temporarily unavailable, and the finished area will be opened. The fire code must be followed at each step of the process to ensure building occupants always have a dependable escape route.
Because of temporary exit paths and travel distances that exceed the code limitations during construction, oftentimes we are asked to perform a timed egress analysis that usually (but not always) includes a smoke model. In a timed egress analysis, we are able to calculate the required egress time it takes for an occupant to leave the building. The objective of the analysis is to determine if the additional travel distances have any impact on the life safety of occupants when compared to the design fire scenario and/or smoke layers from a fire.
Your complex building project may require the consultation of a dedicated fire protection engineer. We try to get involved early to help alleviate the concerns of the Authority Having Jurisdiction (AHJ), and if strict compliance is not possible, provide alternative approaches with at least equivalent, if not better, protection schemes than the code. If you’re renovating, or planning to renovate, your facility and need help with fire code consulting, we can help. Contact us using the form below:
By Jeff Harrington, CEO and Founder of Harrington Group, Inc.