Garage Door System GuideC.H.I. Overhead Doors and Clopay are two established steel garage door brands, and both publish detailed specs. This page lays those published numbers next to each other. It does not crown a winner, because the right door depends on your climate, budget, and which model within each line you compare.
How to read this comparison
Brand-level specs are only meaningful when you compare like models. Both brands sell a ladder from non-insulated builder doors to premium polyurethane doors, so match like model tiers and like insulation types. Read R-value carefully too, because manufacturers may publish a calculated door section R-value rather than a tested installed U-factor, and DASMA says those two numbers are not comparable. Treat everything below as manufacturer-published figures for specific product lines.
What C.H.I. publishes
C.H.I. states its doors are primarily constructed from Nucor steel, except full-view, which is aluminum, and overlay carriage house, available in steel, wood, or fiberglass. It offers three insulation levels, non-insulated, polystyrene, and polyurethane, and states that polyurethane provides the highest R-value and best thermal performance.
For its Sterling line, C.H.I. publishes model 2717 with polyurethane at R-15.07 and model 2783 with polystyrene at R-10.29, both in 2-inch thick 2-sided 24-gauge steel construction, and states it provides a limited lifetime warranty that varies by model.
What Clopay publishes
Clopay states its Intellicore insulation is polyurethane foam injected between the steel layers of the door. It lists Intellicore R-values reaching 20.4 on the Canyon Ridge Carriage House 5-layer 2-inch door and 18.4 on multiple other models.
Clopay offers its steel doors in one, two, or three layer construction with insulation choices of 2-inch or 1-3/8-inch Intellicore polyurethane, polystyrene, or 1-5/16-inch vinyl backed polystyrene, and states its baked-on polyester paint finishes resist chipping and rusting.
Where they differ on paper
Both brands agree in principle that polyurethane delivers the highest R-value, but their published ceilings differ by line. C.H.I. publishes its Sterling polyurethane model 2717 at R-15.07 in 24-gauge 2-sided steel, while Clopay publishes Intellicore R-values reaching 20.4 on select Canyon Ridge doors. Those figures come from different models and thicknesses, so they are not a like-for-like ceiling comparison.
Both offer polystyrene and polyurethane options and back doors with a limited or limited lifetime warranty. C.H.I. emphasizes Nucor steel sourcing and US manufacturing, while Clopay emphasizes its injected Intellicore process. Matching specific models and insulation types matters more than the brand name.