Guide to Insulated Garage Doors

For many homeowners, the garage is one of the primary entrances of the home. It is often also the largest entrance on your home’s exterior. Because of this, the garage can be one of the biggest problem areas for heat loss in your home, impacting your home’s energy efficiency.

The best way to reduce heat loss through your garage is to install an insulated garage door. Along with increased energy efficiency, garage door insulation offers additional benefits, such as quieter operation and increased overall door strength and durability.

Benefits of Garage Door Insulation

Reduced Heat Loss through Your Garage

An insulated garage door prevents heat from escaping through your garage in the winter, meaning it may require less energy to heat your home. In warmer seasons or climates, insulation prevents excess hot air from getting into your garage, meaning lower cooling costs and increased comfort while using your garage.

Customer review of the importance of insulation for heat

Because many garages are connected to the rest of the home (often called attached garages), this can have a big impact on your home’s overall comfort. For example, many garages lead into a high-traffic area of your home like a hallway or kitchen, or there are rooms above the garage. As the image here represents, this makes it easy for cold air to spread throughout the home in the winter as it enters through your garage. This will inevitably happen as you use your garage, but choosing a garage door with insulation minimizes heat loss that occurs even while your garage door is closed.

Illustration of how air flows through your house via the garage

Want to see the impact for yourself? One homeowner put their new Clopay® insulated garage door to the test to see firsthand the difference insulation can make. In the figures below, the homeowner compared their old non-insulated garage door to a door with Clopay® Intellicore® insulation.

Previous garage door was uninsulated and unattractive. Homeowner upgraded to an Clopay insulated Gallery Collection door
This beautiful insulated gallery door was our ImagineNATION winner in November, 2016


Before Clopay® Insulated Garage Door

Date Time Temperature
Inside Garage
Inside Garage
January 17th 8:30 PM 53 ˚ 34 ˚ 19 ˚ warmer
January 20th 10:00 PM 48 ˚ 37 ˚ 11 ˚ warmer
January 21th 12:30 PM 47 ˚ 20 ˚ 27 ˚ warmer
January 24th 5:00 PM 36 ˚ 10 ˚ 26 ˚ warmer
Average - 46 ˚ 25 ˚ 21 ˚ warmer
Original garage door with wood construction. See homeowner data.

With Clopay® Intellicore® Insulated Garage Door

Date Time Temperature Inside Garage Outside Temperature Difference Inside Garage
January 25th 10:00 AM 44 ˚ 2 ˚ 42 ˚ warmer
January 27th 10:00 PM 54 ˚ 2 ˚ 52 ˚ warmer
January 28th 7:30 AM 47 ˚ -7 ˚ 53 ˚ warmer
January 29th 7:30 PM 43 ˚ -5 ˚ 48 ˚ warmer
Average - 47 ˚ -2 ˚ 49 ˚ warmer
Clopay® garage door with Intellicore® insulation installed by EZ Garage Doors & Home Exteriors, North Versailles, PA.

Better Sound Isolation

Insulation also reduces means your garage door operation will be quieter. The figures below represent the difference in decibel levels between a non-insulated garage door and a residential garage door with Clopay® Intellicore® Insulation technology.

Non-Insulated Garage Door Garage Door with Clopay Intellicore Insulation Comparison
Sound Volume (dB) 96dB 80dB Approximately 3x quieter
Decibels are measured on a logarithmic scale, which is why this 16 dB difference has such an effect on the perception of volume levels!

Comparing Insulated Garage Doors

If you are shopping for a garage door with insulation, you may see a few different numbers provided that measure the effectiveness of the insulation. Here is a brief definition of each:

A garage door’s R-value represents its ability to slow the transmission of heat. A higher R-value means a slower transmission of heat, which means less cold air leaking into your garage in the winter and less heat invading your garage in the summer. When it comes to R-values for garage doors, the higher the better!

R-value is the most widely used measurement for a garage door’s energy efficiency. Clopay® uses door section R-value’s for our garage door insulation testing, which is in accordance with the Door and Access Manufacturers Association guidelines provided in TDS-163. Clopay garage door R-values depend on the door’s thickness, material and type of insulation, and range from 6.3 to 20.4. See each Collection or sell sheet for options.

Though not used as often as R-value, U-factor is another number you may see when shopping for a garage door. U-factor represents the flow of heat through a material, meaning the lower the U-factor, the better. Because these are not used across all residential garage door manufacturers, Clopay’s energy efficiency calculations instead currently focus on R-value.

Polystyrene vs. Polyurethane Garage Door Insulation

Polystyrene and polyurethane are the two most common types of garage door insulation. To compare doors and fully understand which is best for your home, knowing the difference between the two is necessary.

Polystyrene Garage Door Insulation
Polystyrene insulation is used in many garage doors and is the type of insulation offered in aftermarket garage door insulation kits sold at major retailers. This insulation comes in the form of rigid panels of polystyrene that are inserted between steel layers of your garage door or placed inside of your single-layer garage door and typically includes a vinyl back.

Garage doors insulated with polystyrene sandwiched between two steel layers will have a quieter operation and energy efficiency than a non-insulated door, however, they are not as energy efficient as foam injected polyurethane.

Polyurethane Garage Door Insulation
Polyurethane is an energy-efficient material used in Clopay’s proprietary Intellicore® insulation technology. This form of insulation is comprised of a polyurethane foam that is injected in between the door’s steel layers, expanding to fill all of the nooks and crannies of the door. The foam bonds to the door’s frame as it expands, further increasing the strength of the door and making it less susceptible to dents.

Garage doors with polyurethane insulation will provide the highest level of sound isolation and climate control, and are a great choice if you live in very cold or hot climates and your garage door is used as the primary entrance to your home.

Below is a breakdown of which insulation types are available for Clopay® garage door collections:

Close up of a cutaway section of door showing polystyrene insulation
Closeup of a cutaway section of garage door showing polyurethane insulation
Collection Series Polystyrene Insulation Available Intellicore® Polyurethane Insulation Available
Canyon Ridge Limited Edition - 2" Intellicore® insulation with thermal break
Canyon Ridge Ultra-Grain - 2" Intellicore® insulation with thermal break
Canyon Ridge Modern - 2" Intellicore® insulation
Coachman - 2" polystyrene or 1-3/8" polystyrene with thermal break 2" Intellicore® insulation with thermal break
Grand Harbor - 1 5/8" polystyrene insulation -
Gallery - 1-3/8" polystyrene or 1-5/16" vinyl-backed polystyrene insulation 2" or 1-3/8" Intellicore® insulation
Classic - 2" or 1-3/8" polystyrene or 1-5/16" vinyl backed polystyrene insulation 2" or 1-3/8" Intellicore® insulation
Modern Steel - 2" or 1-3/8" polystyrene; 1-5/16" 2" or 1-3/8" Intellicore® insulation
Classic™ Wood - Polystyrene insulation (Model 33 only) -
Reserve® Limited Edition Polystyrene insulation -
Reserve® Modern Polystyrene insulation -