Chattanooga TPO Roof Replacement with a 368-Panel Solar Array at Developmental Resource Center
Updated: Sep 3
Location: Chattanooga, Tennessee
Industry: Energy & Power
Service: Infrastructure & Utility Modernization
The Situation
The City of Chattanooga needed to replace more than 25,000 square feet of roofing at the Development Resource Center while integrating a new 368-panel photovoltaic array. The work required more than a new membrane: the completed roof had to accommodate 45 tons of structural steel, specialized column penetrations, electrical work, and solar installation while maintaining continuous weather protection and manufacturer warranty requirements.
The Challenge
Conditions at the parapet walls did not match the anticipated structural configuration. At 17 locations, the newly designed solar-support columns conflicted with existing steel conditions. Connections and column configurations had to be modified in the field, and each support had to pass through the new roofing assembly without interrupting the continuity of the TPO membrane.
The existing roof presented additional concealed conditions. Previous solvent contamination affected portions of the roof surface and required enhanced cleaning and priming before membrane tie-ins could be completed. Deteriorated and incompatible parapet substrates also prevented the new flashing and edge-metal systems from being installed directly over the existing construction.
Roofing, structural steel, electrical, and photovoltaic work had to advance in a coordinated sequence. Completed membrane areas required protection from follow-on construction, while temporary dry-in measures had to be maintained and adjusted as weather and field conditions changed.
How We Worked
JBrennon removed the existing roofing assembly and debris before installing sloped rigid insulation, tapered insulation, cover boards, and a new 80-mil TPO membrane system. Areas affected by solvent contamination were cleaned and primed to establish suitable surfaces for membrane adhesion and tie-ins.
The solar-support structure included approximately 45 tons of structural steel. JBrennon coordinated the fabrication and erection of custom-configured columns and modified connections at the 17 conflicting parapet locations. Steel components were shop-primed and field-painted, and the structural work was completed to the applicable AISC requirements.
Framed bump-out enclosures were constructed around the column penetrations. Prefabricated TPO-compatible pipe boots and metal flashing isolated dissimilar materials while preserving the continuity of the roofing system around each support.
At the parapet perimeter, JBrennon installed pressure-treated wood blocking to receive the new membrane flashing and edge-metal assemblies. Plywood sheathing was applied to the interior and top faces of the parapets, followed by tapered XPS insulation to promote positive drainage. High-wind-rated edge metal was embedded in water-block to complete a continuous weathertight perimeter.
Additional finished work included overflow drains, walk-off mats, prefinished metal flashing, vent-pipe boots, and localized structural deck repairs. Roofing activities were sequenced with the electrical and photovoltaic trades so the 368-panel array could be installed while completed membrane areas remained protected.
The Outcome
JBrennon delivered a coordinated roofing and renewable-energy upgrade at the Development Resource Center. The finished project combined a new high-performance TPO roofing system with the structural infrastructure and specialized detailing needed to support a 368-panel photovoltaic array.
More than 25,000 square feet of 80-mil TPO roofing installed
Approximately 45 tons of structural steel erected
New 368-panel photovoltaic array integrated with the roofing system
Structural connections modified at 17 parapet locations
Contaminated roof surfaces cleaned and primed for membrane adhesion
Parapet substrates rebuilt with blocking, sheathing, tapered insulation, and high-wind edge metal
Temporary dry-in and protected work sequencing maintained during roofing and solar installation