Layered Approach: Garage doors with polyurethane or polystyrene cores can achieve R-values of more than 20 to help insulate the garage.
Layered Approach: Garage doors with polyurethane or polystyrene cores can achieve R-values of more than 20 to help insulate the garage.

Opening your garage door in the winter isn’t like opening your front door whereby a gust of cold air dissipates in the conditioned space. Even if the garage is insulated and drywalled, it’s an unconditioned living room–size space that just stays cold. So what’s the virtue of an insulated garage door if it’s not keeping heat in? Manufacturers offer some insight.

1. Warmer for sure: In the winter, garages with insulated doors get cold, but not necessarily freezing. That’s an important distinction, notes Clopay senior product manager Justin Evans. “If it’s 20 degrees outside and all you have is a [non-insulated] pan door, your garage temperature will be around 30 degrees,” he says, citing data from the Clopay engineering department. With an insulated door, that temperature is closer to 42 degrees. “One’s below freezing and one’s above freezing. That makes a big difference.”

Wayne-Dalton marketing director Kevin Jones adds that in very cold regions, “some people can’t get their cars started in the winter if the garage temperature is too cold.” Both manufacturers offer garage doors insulated with polystyrene or polyurethane.

2. Vestibule effect: Jones also suggests that a garage secured by an insulated door acts as a buffer zone between the home’s conditioned space and the great outdoors. Restaurants are a classic example of this vestibule construction. “If you look at it as a buffer space,” Jones says, “you’re not blasting everyone with cold air just by entering the garage.” Many homes have conditioned spaces above the garage that also benefit from this vestibule zone.

3. Quieter operation: There’s nothing quite like a noisy garage door to raise the alert that someone is leaving the house early or coming home late. In addition to a more finished interior appearance, Todd Miller, owner of QMA Design Build, in Ventnor, N.J., says that he selects insulated doors because “they seem to rattle significantly less than non-insulated doors.”

4. All-around toughness: Manufacturers agree that denser polyurethane offers significantly more insulation value than a polystyrene core, but both are better than nothing when it comes to strengthening a garage door. “Think about your kids throwing a basketball against a pan door,” Evans says. “It just won’t stand up to that. People don’t realize how much abuse a garage door takes.” Insulation adds rigidity to the door panels, helping them withstand certain impacts, as well as the stress of constant raising and lowering.

  • Garage Doors by the Numbers

  • 7 out of 10 homeowners rely on the garage door as their primary entrance. -LiftMaster

  • 75.4% The average return-on-investment for a garage door replacement project.
    -2013 Remodeling Cost vs. Value Report

  • $3.075 Billion The approximate industry revenue attributable to repair and installation on existing residential buildings. -IBIS World

—Lauren Hunter is the senior products editor at REMODELING. Find her on Twitter at @LaurenHunter_HW or @RemodelingMag.