Start below the membrane
Verify deck type and condition, existing layers, vapor or air-control needs, insulation, slope, attachment, and wet-area removal. The membrane cannot compensate for a poorly defined substrate.
Define attachment and details
Mechanically attached, adhered, and induction-welded assemblies behave differently. Perimeter zones, corners, curbs, penetrations, walls, edges, and equipment supports need explicit details.
Coordinate warranty and manufacturer requirements
Approved contractor status, fastening density, sheet width, membrane thickness, accessories, detail methods, inspections, and warranty term can all affect price and installation.
Practical owner checklist
- Verify deck, existing layers, and wet insulation.
- Define insulation, attachment, membrane thickness, and detail requirements.
- Coordinate drainage and rooftop equipment.
- Normalize manufacturer warranty scope across bids.
Frequently asked questions
Is thicker TPO always better?
Thickness can improve durability margin, but system design, attachment, reinforcement, details, workmanship, and exposure also matter.
Should all TPO bids use the same manufacturer?
Not necessarily, but equivalent performance and warranty requirements should be clearly defined if multiple manufacturers are allowed.