Project Type: Evaluation, Design
The Vital Structure:
Roof Structure Replacement and Related Work
Issue
Vital Structures was hired to assess the extent of structural damage resulting from a recent fire. The single-story gas station and convenience store was reportedly constructed in 1934 and consists of brick masonry first-floor exterior walls and a wood framed roof structure. The building reportedly experienced a fire event on July 13, 2023, which was extinguished by cutting through the existing roof sheathing and placing firehoses into the attic space. Due to the fire damage, the Contractor intended to completely remove and replace the entire building roof framing and retained Vital Structures to review the existing supporting structural elements.
Diagnosis
Our evaluation of the existing structural walls, beams, connections, and foundations noted that the existing perimeter upper-wall timber sills were not anchored into the masonry walls, and experienced varying degrees of fire damage and deterioration, requiring replacement. Existing attic joists were not present, compromising the lateral stability of the building. Deterioration of exterior brick masonry wall mortar joints, locations of displaced masonry, and fire damage to non-load bearing interior walls were observed.
Solution
Our design included new 2×10 roof rafters, new plywood roof sheathing, and new LVL attic joists, supported on triple LVL perimeter sills anchored into the top of the exterior masonry walls, as well as replacement of fire damaged wall studs, headers, top wall plates, and sill plates. Rebuilding of sections of the exterior masonry walls, where loose and displaced bricks were observed, was specified, as well as repointing of deteriorated mortar joints.
Result
The roof structure replacement and related repairs will allow the owner to reopen their business following the fire event, and with the addition of anchored sills and attic joists, will provide a building with improved lateral stability.
Evaluate. Guide. Revitalize.
Let's Do Something Vital Together!