Is Insulating a Garage Door Necessary?

Insulating your garage door is an often overlooked, but important step in making your garage – and even your entire home – more energy efficient. There are several key reasons why insulating a garage door is recommended.

Heat Loss Through Garage Doors

Garage doors can be a major source of heat loss in winter and heat gain in summer. The large surface area and lack of insulation means that energy escapes easily from conditioned spaces of the home into unconditioned garage areas.

Studies have shown that an uninsulated two-car garage door can account for up to 25-30% of total heat loss in a home. Properly insulating a garage door provides a thermal break between the inside conditioned areas of the home and outside elements.

Reduced Energy Bills

Adding insulation helps reduce conductive heat transfer through the garage door materials. This decreases the amount of energy required to maintain comfortable temperatures in the adjoining spaces of the home.

The U.S. Department of Energy estimates that adding R-10 insulation to an uninsulated two-car garage door can reduce heating and cooling costs by 8-12% annually. Insulation helps block outside air from infiltrating into the garage and subsequently the rest of the home. Warm air is kept inside during winter. Cool air is retained inside during summer. This efficient air sealing directly translates into lower utility bills.

Improved Temperature Control

Insulating a garage door helps prevent the extreme external temperatures from influencing the internal garage temperature fluctuations. The conditioned spaces of the home that share walls with the garage will experience less temperature variation.

By moderating the garage interior temperatures, an insulated garage door promotes energy savings by reducing the workload on heating and cooling systems. Any temperature extremes get buffered before reaching living areas on the other side of the adjoined walls.

Reduced Noise

The solid construction of an insulated garage door creates an effective sound barrier from outside noise. The insulation helps dampen the transmission of noise from the garage into adjoining interior home spaces. This is especially beneficial if the garage is located beneath a bedroom or living area.

Added Curb Appeal

Along with functionality and efficiency, an insulated garage door offers aesthetic appeal. Contemporary insulated garage doors are available in attractive materials and appealing designs to enhance the overall look of your home. Going with an energy efficient insulated model over a standard uninsulated door is an easy way to upgrade your home’s curb appeal.

Types of Garage Door Insulation

If you’re wondering how to insulate a garage door, there are a few material options to consider:

Polyurethane Foam Insulation

The most common type of garage door insulation is polyurethane foam. It offers an optimal balance of high-performance insulation properties and cost-effectiveness.

Polyurethane foam has an R-value of around R-6.5 per inch. This means that a typical 1.5-2 inches of foam insulation provides an R-value of R-10 or more, meeting or exceeding the recommendations for most climate zones.

Polyurethane insulation is lightweight, durable and long-lasting. It adds structural stability while being flexible enough to conform to the garage door panels.

Polystyrene Insulation

Polystyrene is another rigid foam insulation that can be used for garage doors. It has a similar R-value to polyurethane foam.

It can be injection molded into door sections during manufacturing. Some manufacturers also utilize layered polystyrene insulation boards.

Polystyrene is costlier than polyurethane foam. However, it does offer excellent insulating properties for the increased price.

Fiberglass Insulation

Fiberglass insulation batts or rolls can sometimes be an option for garage doors, depending on the construction. Fiberglass works best for flush panel doors without embossed sections.

Fiberglass insulation is less expensive, but it does not provide the same efficiency or thermal performance as rigid foam insulation. The batts are more prone to settling and compression over time.

Insulated Garage Door Panels

For maximum efficiency, opt for a door constructed using polyurethane insulated panels. The foam is sandwiched between an interior and exterior metal skin for optimal stability and insulation capacity.

Some manufacturers inject the foam right into the door sections during fabrication for seamless coverage and bond. The tongue-and-groove panel connections also help block airflow and infiltration.

How Much Insulation Do You Need?

Most insulated garage door models range from R-6 to R-18 insulation value. R-10 is typically the minimum recommended, but going with the highest available R-value for your climate is ideal.

For hot climates, prioritize solar heat gain resistance with options like reflective coatings. For cold climates, focus on maximum R-value to counteract winter heat loss.

In extreme northern or southern regions, R-12 to R-18 insulation provides excellent thermal protection and energy savings. The insulation requirements also depend on your garage size, exposure, and how much it is connected to conditioned home spaces.

Is it Worth Insulating an Existing Door?

If your current garage door is uninsulated, adding insulation can be a worthwhile upgrade. Inserting custom cut sections of rigid foam board between the panels is one option. However, effectiveness is limited depending on the door’s structure.

The ideal solution is upgrading to a new modern door with factory-installed high quality insulation. You will maximize energy efficiency, cost savings, and functionality.

When deciding whether to insulate an existing garage door or install a new one, consider your climate, the projected utility savings, and your budget. Weigh the added costs against long-term energy efficiency returns.

Other Garage Door Improvements

Along with insulation, here are some other worthwhile upgrades to consider:

  • Weatherstripping – Add weatherstripping along the perimeter of the garage door to seal air gaps that allow outside air infiltration. Quality weatherstripping compresses when the door closes to block drafts.
  • Automatic door bottom seal – This seal attaches to the foot of the door to seal the gap along the floor as the door shuts. It provides an air tight barrier along the bottom edge.
  • New opener – A new opener can provide improved insulation along with better security, safety and convenience features. Openers with wall-mounted push button controls avoid cold air entering the garage through overhead ropes.
  • Windows – Switch out standard windows with insulated, double-pane glass windows to reduce condensation and heat loss. Consider fogged, frosted or tempered glass for reduced visibility.
  • Steel vs fiberglass – Steel doors offer more durability and better insulation than less expensive fiberglass doors. There are pros and cons to weigh for your needs and budget.
  • Wood overlay – For appeal, a wood overlay adds curb appeal to a steel base door without compromising insulation and durability.


Installing proper insulation is one of the best ways to improve your garage door’s energy efficiency. The right insulation provides a barrier against temperature extremes and reduces conductive heat transfer into or out of your home spaces.

Newer garage doors with quality foam insulation offer long-term performance and significant energy savings. For most homes, choosing an insulated garage door with at least R-10 insulation is well worth the investment for lower energy costs, reduced noise, and better temperature control. Properly insulating your garage door is one upgrade that can pay dividends for years to come.

FAQs About Insulating Garage Doors

Should you insulate a detached garage?

Yes, even a detached garage should be properly insulated. The conditioned spaces of the home, like a bonus room or apartment over the garage, benefit from insulating the walls and doors. An insulated detached garage will also stay cooler in summer and warmer in winter for comfort when accessing contents.

What is the best insulation for garage doors?

Polyurethane foam insulation often provides the optimal combination of effective R-value, cost, and durability for most garage doors. Many modern doors feature sturdy polyurethane foam injected between a steel base layer and exterior metal skin for seamless coverage.

Do you need a vapor barrier for garage door insulation?

No, a vapor barrier is generally not needed when insulating garage doors. The water resistant properties of materials like polyurethane foam provide adequate moisture and condensation control.

Are insulated garage doors heavier?

Yes, the weight of an insulated garage door is typically a bit heavier than an uninsulated door. However, torsion spring systems allow even large insulated doors to open and close conveniently with an automatic opener. The foam insulation adds thermal mass which can help maintain interior garage temperatures as well.

Should you insulate garage attic space?

Insulating garage attic spaces that connect directly to home living areas is recommended. Heat rising from the garage attic can transfer into the adjoining attic above living spaces. Proper insulation and air sealing of the garage attic helps prevent temperature transmission.

How do you soundproof garage doors?

Using a steel or solid wood garage door rather than fiberglass provides better sound dampening. Make sure the door seals tightly along the perimeter when closed. Adding polyurethane foam insulation inside garage door panels also helps reduce noise transmission from the garage into interior home spaces.

Is it cheaper to insulate an existing garage door or buy new?

In most cases, investing in a brand new insulated garage door is the more cost effective option long-term. Attempting to add insulation to an existing door is often limited or ineffective. New doors provide complete, factory installed insulation for optimal efficiency and savings on energy bills over time.

How much does insulating an existing garage door cost?

The cost to add insulation to an existing door depends on method, materials, door size and labor. Basic DIY options range from $100-$500. Having professional foam board installation typically costs $400-$1,200. The investment for a new insulated door starts around $500-$1,500 with professional installation.

How long does insulating a garage door take?

A full garage door insulation project typically takes 2-5 hours, depending on size and method. DIY kits can be installed in an afternoon. Having a contractor add rigid foam boards or replace the door usually takes 4-6 hours. New door installation is often completed in a single workday.