Insulated Commercial Garage Doors Vancouver — R-Value, Polyurethane, and What Actually Matters

R-value is the number the door industry uses to sell insulated commercial doors and it is frequently misunderstood. A door rated R-16 does not perform like a wall rated R-16. The door is a smaller portion of the opening than the wall area, it has frames and tracks that conduct heat differently than the panel, and the seal perimeter matters as much as the panel insulation.

Polyurethane vs Polystyrene

Commercial insulated doors use one of two foam insulation types. Polystyrene is cut-to-fit rigid foam inserted into a pre-formed panel cavity and sandwiched between the inner and outer steel faces. Polyurethane is foamed-in-place — liquid chemicals are injected into the panel cavity and expand and cure to fill the cavity completely, bonding to both steel faces. Polyurethane is superior for commercial applications for three reasons. First, higher R-value per inch — polyurethane runs R-6 to R-7 per inch, polystyrene runs R-4 to R-5. Second, structural — the foamed-in-place polyurethane bonds to both steel skins and creates a structural composite panel that resists denting better than a polystyrene insert. Third, no air gaps — polystyrene panels can develop gaps at the edges as the foam shrinks slightly over time. Foamed-in-place polyurethane fills completely and maintains that fill.

Thermal Break Construction

A commercial steel door panel has an outer steel face, insulation, and an inner steel face. If the outer and inner faces are in direct contact at the panel edges the steel edge acts as a thermal bridge bypassing the insulation entirely. Thermal break construction interrupts this path. A non-conducting material separates the inner and outer steel faces at the panel edges. On Amarr commercial thermal break panels the effective R-value is meaningfully higher than on non-thermal-break panels of the same nominal thickness.

Installation Quality and Seal Perimeter

The best-specified door in the world performs poorly if it has a failed seal perimeter. We have inspected commercial doors with excellent panel R-values that had visible daylight at the side seals and a bottom seal that was completely flat. The thermal performance of that door was poor regardless of what the spec sheet said. For insulated commercial door installation and service across Metro Vancouver call (604) 206-5727. We spec the door to the application not to the price point.