Project Type: Evaluation, Design
The Vital Structure:
Rising Masonry Wall Repairs
Issue
Vital Structures was retained to perform water leak testing to evaluate the two (2) active leak areas located on the second floor of the building. The building is a multi-story, 347,168 SF Class A laboratory and office building that spans over a city block in length and was originally constructed sometime in the late 1940’s-early 1950’s as a warehouse and distribution center. An extensive rehabilitation was performed in 1981 which added the second-floor mezzanine spaces and six (6) metal panel steep slope roofs. In 2017, the current owner of the building performed a core and shell rehabilitation that included limited curtain wall replacement, a large atrium roof skylight, selected building envelope repairs.
Diagnosis
Targeted, programmatic water leak testing was performed at roof drains and rising wall components located in the vicinity of the reported leaks. Water infiltration above the ceiling of the second-floor areas was observed when water was applied to an observed tear in the roof membrane, which was patched by the roofing contractor during the evaluation. Water infiltration was also observed when water was applied to two (2) distinct areas of rising wall brick masonry, which exhibited signs of failed mortar joints and abandoned anchors into the brick. Following leak testing, exploratory masonry test cuts were performed, which revealed deficiencies in the through-wall flashing of the masonry rising wall.
Solution
Our design for repair included removal of existing brick masonry approximately 2’-6” above the existing through-wall flashing along the full length of the rising wall, removal of existing through wall flashing, replacement of deteriorated gypsum wall sheathing, installation of new KEE through-wall flashing membrane, new stainless steel counter flashing, new weep baffles and mortar nets to protect the weeps from blockage, replacement of brick masonry, and replacement of PVC flashing membrane at the roof to rising wall transitions.
Result
The repairs to the brick masonry, through-wall flashing, and roof-to-wall transition flashing resolved the reported leak issues within the second-floor space, saving the Owner from future expenses from damages to finishes and equipment caused by water infiltration. The improved waterproofing detailing of the new design will also prevent future damage to structural framing and extend the life of the facility.