This roof was a challenge. It had a combination of metal, modified built up and SPF (Spray polyurethane foam) roofing on it. However, it was all damaged and was paid for by insurance.
We went with a fully adhered system for the new TPO roof. We also used mechanical fasteners on the insulation for additional support. We wrapped all of the walls between the different roof types to make sure there were no leak points on the roof.