# Delmar Loop Commercial TPO Project > 14,000 sq ft of 60-mil adhered TPO, welded and shipped in a single weekend. Project file C0834. Canonical: https://donovanrc.com/projects/delmar-loop-flat/ ![Automated TPO seam welder on a commercial flat roof](/wp-content/uploads/donovan/photos/commercial/auto-seam-welder.webp) [Back to projects](/projects) Project file C0834 · 2024 # A 14,000 sq ft TPO on the Delmar Loop, shipped in one weekend. 60-mil adhered TPO, walk-behind seam welder, single-weekend schedule. Customers parked at 9am Monday in the same lot we had owned all weekend. Delmar Loop, St. Louis The owner called on a Tuesday. The current roof had failed at the parapet over the prep kitchen and a third of the dining floor was getting damp during every rain. By Thursday a Donovan foreman was on the roof with a moisture meter and a plan. The constraint was the parking lot. The restaurant could not lose a weekend of dinner service plus a Monday lunch. We scoped a Friday-after-close to Sunday-by-sundown window (forty-eight hours, three crews, two shifts) and held a kickoff meeting in the owner's office with the timeline taped to the wall. Friday at 11pm the tear-off crew came down. Saturday at 6am the membrane crew came up. Sunday at 5pm we walked the roof with the owner, peel-tested every seam, and pulled the lift off the property. By 9am Monday the only sign we had been there was a slightly cleaner gutter. ![Worker with TPO seam welder](/wp-content/uploads/donovan/photos/commercial/tpo-seam-welder.webp) How the work moved ## Six weeks in five acts. Act 01 ### Walk it twice. The foreman walked the roof on Tuesday with a moisture meter and again on Thursday with the GC. We mapped every penetration, every drain, every parapet height, and built a pull-list for the shop. Act 02 ### Pre-fab everything off-site. All curbs, drain boots, and parapet caps were measured, cut, and pre-welded in the shop the week prior. When the membrane crew arrived Saturday morning, every detail piece was already on a pallet labeled by zone. Act 03 ### Tear off after close on Friday. Restaurant locked at 11pm. Crew on the roof by 11:30. Old membrane gone, decking inspected, eight panels of soft insulation replaced before sunrise. Act 04 ### Adhere the field on Saturday. 60-mil TPO, fully adhered with low-VOC bonding adhesive. Walk-behind seam welder on every long run; hot-air gun on every corner. Two foremen, two crews, twelve hours. Act 05 ### Detail Sunday morning. Drain boots set in cold sealant, parapet caps soldered down, penetration boots heat-welded and inspected. By noon Sunday the field was complete and the inspection crew started in the corners. Act 06 ### Peel-test every seam. Sunday afternoon: gauge in hand, foreman walked every seam, pulled to twelve pounds. Two seams re-welded on the spot. Final clean by 5pm. Lift off the property by 6pm. Monday morning, dinner service. ![Worker with TPO seam welder](/wp-content/uploads/donovan/photos/commercial/tpo-seam-welder.webp) ![Automated walk-behind seam welder](/wp-content/uploads/donovan/photos/commercial/auto-seam-welder.webp) ![Two hands using heat-welder on TPO](/wp-content/uploads/donovan/photos/commercial/two-hands-welder.webp) ![Heat welder with red pressure roller](/wp-content/uploads/donovan/photos/commercial/welder-red-roller.webp) ![Cutting TPO with a utility knife](/wp-content/uploads/donovan/photos/commercial/utility-knife.webp) ![Commercial flat roof with masonry parapet](/wp-content/uploads/donovan/photos/commercial/flat-roof-parapet.webp) ![Heat-weld gloves working a TPO seam](/wp-content/uploads/donovan/photos/commercial/heat-weld-gloves.webp) From the foreman > “Dinner did not skip a service. That is what a commercial roof is for.” Donovan crew foreman, project C0834 Bring us in ### Your roof has its own story to tell. [Request a visit](/contact) What homeowners are saying - > “Justin did a great job of communicating and was on the job site a lot.” Gerald K. · Google - > “Nick Mirth did an excellent job throughout the process our insurance claim!” Tim C. · Google - > “Great experience, very knowledgeable and customer friendly. I would highly Recommend.” Kathy O. · Google [See all reviews](/reviews)