Project Type: Evaluation
The Vital Structure:
Structural Assessment for Roof Top Unit Replacement, New Bedford, MA
Issue
Vital Structures was retained by a licensed mechanical contractor to perform a structural assessment of an existing roof top unit at a bus depot in New Bedford, MA. Our client was hired to replace the existing roof top unit with a new, more efficient system. However, the building department has required that a structural engineer review the existing building framing and proposed roof top unit, in an effort to determine whether the building framing has the capacity to support the new system. An engineer’s letter of approval is required, prior to issuance of a building permit.
Diagnosis
Vital reviewed the existing roof framing, unit location, unit model number and potential areas for snow drift. We compared the weights and size of the proposed system to the existing system observed while on-site, so that we could perform a load comparison.
Result
Following review of the proposed and existing systems, as well as review of the existing roof framing, Vital Structures determined that the proposed roof top unit would not increase the loading, nor change the load path into the roof structure below. Therefore, we provided our client with a certified letter that describes these findings, so that it may be shared with the local building official.