High-Rise Student HousingPhiladelphia, PA
This fourteen-story student housing apartment complex is located in downtown Philadelphia. The claim involved a roof membrane on the 14th and 13th floors which had become detached as a consequence of strong winds.
Given that the roof had been recently installed, there was concern as to why such damage occurred so soon.
MKA was retained to investigate both cause and cost of repair for this high-rise student housing project.
There was no visual pattern to the failure that allowed for an easy analysis, so MKA was tasked with undertaking roof membrane uplift tests and roof core cuts, along with moisture surveys to establish the failure mechanism and contributing factors.
Our preliminary visual and non-destructive infrared testing revealed the presence of moisture, but yielded no useful information regarding the cause and underlying conditions of the failed roof sections.
MKA performed an uplift test to establish the wind uplift resistance of undamaged roof areas, along with core cuts to verify the conditions throughout the roof assembly.
These observations revealed that the paper adhesion surface of the rigid foam insulation board was wet throughout the roof area even though there was no evidence of damage (roof cuts or tears) for the moisture to enter the roof section.
The wet paper facer resulted in a reduced adhesion capability, significantly affecting the wind uplift resistance of the roof membrane.
The presence of moisture was a result of a failure to design and install a vapor barrier on the roof deck. This faulty design allowed moisture vapor to migrate from the building interior and condense under the rubber roof membrane, where it wicked into the paper facer.
MKA identified the areas that became de-bonded as a result of the wind storm and culled the costs out of the total replacement. MKA then participated in the subsequent subrogation process.