There were several areas of concern with the existing 2000 low slope PVC roof system including multiple roof patches, fire damage and the generally aged roof membrane. Vital Structures performed an evaluation of the existing PVC membrane roof system; including a review of limited original design documents, exploratory test cuts, and a comprehensive evaluation of the roof system including structural review per 2015 IEBC Chapter 7 – Alterations Level 1, structural analysis for new rooftop HVAC equipment loading, roof drainage calculations, insulation energy code requirements review, and localized wood roof deck evaluation for replacement. The following conditions were noted by Vital Structures:
- The existing PVC roof system had surpassed its useful life expectancy and required removal and replacement. The new roof system was to include high puncture and chemical resistance due to expected rooftop equipment maintenance and restaurant exhaust containing grease discharge.
- The existing rooftop HVAC equipment, rooftop ductwork and supports were aged with questionable ductwork supports, all requiring removal and replacement (HVAC Engineering by others).
- Roof framing modifications and upgrades were required for the new rooftop HVAC equipment, parapet pediment bracing required by building code and other future rooftop equipment needs.
- The existing steel parapet/pediment bracing was questionable and attached only to the ¾-inch tongue and groove wood roof deck. A new steel parapet/pediment bracing system with associated building roof framing connections was required.
- Improper/non-building code-compliant overflow roof drainage plumbing was identified.
- An existing rooftop brick chimney was observed to be in disrepair and confirmed to be abandoned and not needed.