If your garage feels too cold in winter or too hot in summer, you’ve probably considered insulating it to protect your vehicles better or make the area more usable all year round. Insulating an attached garage is virtually a must, yet many builders don’t insulate attached garages, leaving the rooms next to or above them colder or hotter during certain times of the year. This guide will help you determine your garage insulation cost and help you decide how much of your garage your should retrofit with insulation, along with options to complete the project. The total installed cost to insulate a garage will be somewhere between $720 and $1,150 on average, depending on the size of your garage (i.e. the number of cars accommodated).
Keep in mind that if you want to use your garage in winter as a workshop or for some other purpose, insulating it may not be enough. The same goes if you have extremely hot and humid summers and want a comfortable space. You’ll need to run HVAC into the area through ductwork or a mini-split system, which will add to the ultimate cost. Installing insulation is a relatively easy DIY project, so if you don’t mind the time and mess, you can save considerable money by not paying anyone to do it.
When it comes to materials, garage insulation cost is about 50 cents to $2 per square foot. If you have someone do the work for you, add another 80 cents to $1 per square foot for labor.
For comparison purposes, we will consider a one-car garage with 320 square feet, a two-car garage with 480 square feet, and a three-car garage with 600 square feet.
|Overview of Garage Insulation Cost & Prices
Note that the above figures are averages and include the cost of labor. At the low end of the range, a one-car garage DIY insulation job without drywall can be as little as $200. At the other end of the spectrum, the cost of insulating garages with spray foam insulation can be as much as $9,000. The average price of insulating a garage that already has drywall in place is between $3,000 and $4,000.
Recommended Insulation Levels for Garages
Most older homes with garages have 2×4 studs. These require a lower insulation level of R-13. Newer structures are built with 2×6 studs and require insulation with minimum insulation of R-21.
Wall Insulation Levels
Evaluate and measure your wall studs to determine your minimum insulation levels. Select your R-level based on the type of studs you have. Insulation R-value measures the efficiency of the insulation to stop heater transfer. Generally, the higher the R-value, the better the insulation.
Ceiling Insulation Levels
Most experts will tell you that insulating the ceiling is a must, particularly for homes with rooms above that have rooms above the garage. Many bonus rooms above garages are cold in winter because the floor of those rooms abuts the garage ceiling. Insulation in this area will make both the bonus room and the garage warmer. Choose thicker insulation with an R-40 value. Fiberglass batts and spray foam insulation are the most popular types to install in a garage ceiling. Spray foam insulation on a garage ceiling could cost as much as $1,500 to $3,100.
Types of Insulation Used in Garages
Several types of insulation are appropriate for use in your garage. What you choose depends on your budget, climate, and intended use for your garage.
Sold in rolls or pre-cut batts, fiberglass insulation is the most popular type as it is the easiest type of DIYers to install. Installation is relatively easy if you have exposed studs and works well if you choose to put a vapor barrier over it. Fiberglass is more challenging to install if you already have drywall in place as you may have to replace the drywall in places after installing the batts. Fiberglass is also ideal for garage ceilings in addition to walls. The average material cost is $145 to $200. For a professional job, you’ll need to add a minimum of $200 to $500 for labor. Fiberglass improves energy efficiency by as much as 30% when properly installed.
Reflective or Radiant Barrier Insulation
This is another popular type of insulation that is also relatively inexpensive and easy to install. It’s versatile, dust-proof, and doesn’t collect moisture, so it is best used in hot and humid climates as it tends to work in more types of conditions than other insulation alternatives. You can expect radiant barrier insulation to cost between $700 to $2,900. Radiant barrier insulation is perfect for roofs in hot climates as it is efficient at keeping out the heat. For professional installation, ad another $575 to $750.
Blown-in insulation is excellent if you already have drywall in place and want to insulate the area behind it. Install it by drilling a hole in the wall, blowing the insulation material inside, and then patching the drywall. This type also takes less time to install. However, you should note that it is more expensive than other types, coming in at about averaging $1 to $2 per square foot.
Spray Foam Insulation
Spray foam insulation costs $0.50 to $2 per board foot, depending on whether you seal leaks and gaps inside existing walls. This insulation is ideal for those looking for a relatively inexpensive way to fix a more significant problem. You’ll find two types of spray foam insulation, open-cell, and closed-cell. The latter is more expensive but more energy-efficient.
Foam Board Insulation
Foam board insulation is an excellent alternative if you want to insulate your garage but don’t want to put up drywall over it. However, check with your municipality to see if local building coats allow this insulation type. You should also make sure that the product you use has been flame-tested. Foam boards are typically found in many garage door insulation kits because of their ease of installation. Expect to pay 44 cents to 65 cents per board foot.
Garage Insulation Installation Cost Comparison and Breakdown
Insulation Type Material Price Per Board Foot
- Batting $0.30 – $1.50
- Blown-in $1 – $2
- Spray Foam $0.50 – $2
- Radiant $0.20 – $1
- Rigid $0.25 – $1
How Much Does Garage Insulation Cost?
For materials only, you can expect to spend a low of $128 for a one-car garage to $450 and more for a three-car garage, depending on your insulation choice. Labor costs range from $400 to over $1,600 for professional work.
What About the Cost to Insulate and Drywall a Garage?
Installing drywall in a garage will add to the price paid for insulation.
Cost to Drywall a Garage Only
The cost to drywall a garage is between $1.50 to $3 per square foot for materials and labor, which translates to $1,200 to $5,100, depending on the size. Consider using fire-resistant panels for your project, which cost about 50% more.
How Much Does it Cost to Insulate a Garage Ceiling?
For an average two-car garage of 480 square feet, you’ll have approximately 513 square feet of ceiling space. Installation of fiberglass batts runs from $672 to $886 for the material. Add another $281 to $680 for basic labor.
How Much Does it Cost to Insulate Garage Walls?
Insulating the garage walls will be your highest cost. Find out how much you need by measuring the linear feet around the entire garage and multiplying it by the height of the walls. Buy an extra unit or two in case you make a mistake. Once you have measured your garage walls, you can use this calculator to determine an approximate cost for your garage walls according to the insulation you prefer.
What is the Cost to Insulate a Garage Door?
Consider buying a garage door insulation kit if you currently have an overhead door that is not insulated. These kits come with instructions that make them easy to use. Find them at Big Box stores and through various internet sources like Amazon.com. Pricing starts at about $23 and goes up to over $1,200 for a DIY foam insulation kit. Remember that when you insulate a garage door, you add weight to it, so it’s a good idea to adjust the tension and springs afterward.
How Much Do Pre-Insulated Garage Doors Cost?
The costs vary widely depending on the size of the door and the R-value of the insulation, with the range going from $400 for a one-car overhead door to $10,000 or more for a custom triple door. The average cost of insulated garage doors is $900 to $1,800. R-values for garage doors range from 4 to 19, but most garage doors have an R-value of about 9. An R-18 garage door will keep the interior about 12 degrees Fahrenheit warmer in the winter and 25 degrees Fahrenheit in the summer. Unless you plan to keep the overhead door closed most of the time in extreme weather when planning to use the garage as an extra room, buying a garage door with a high R-value may not be cost-effective as the energy savings will take years to match the additional insulation cot. Insulated garage doors usually have spray or board rigid foam insulation between the interior and exterior panels.
Garage Type Cost Range:
- One-car $1535-$2,750
- Two-car $3,050-$5,550
- Three-car $4,605-$8,250
Garage Door Insulation Costs by Size
The type of insulation used for overhead garage doors affects the price. Generally, you’ll find two different types: polystyrene or polyurethane. Most garage door insulating kits have polystyrene panels that you can either insert between the panels or place on top of them in the garage interior. Polystyrene is more affordable, but it is also less effective. The panels are cut to length and snapped into the space between the horizontal rails on the door panels. This type of kit provides an insulating value of roughly R-4.
When using polyurethane foam, you spray it into the spaces between the panels, where it fills every nook and cranny. This type costs much more but will save money in the long run as it is more energy-efficient.
- Cost to Insulate a Single Garage Door: $50-$70
- Cost to Insulate a Double Garage Door: $100-$140
- Cost to Insulate a Triple Garage Door: $150-$210
Note that the above prices are for foam installation kits. Other types may cost considerably more.
Factors Affecting the Cost of Garage Insulation
Obviously, the size of your garage is the most significant factor affecting the cost of your insulation project. Other factors that will make a difference include the type of insulation you use and whether you decide to put insulation in the ceiling. Adding drywall to the project, which also adds thermal properties, will increase the cost. Retrofitting your overhead garage door versus buying an already insulated door will also affect the total cost.
Timescale for Garage Insulation Installation
The time needed to perform the actual job isn’t long, generally, one to two days, depending on how big your garage is, so theoretically, you can do the job in one weekend. Other considerations that add to the timescale are shopping for the tools and materials needed to complete the job, possibly bringing them home if you don’t have them shipped, and clearing your garage of vehicles and other stored items. Budget several hours to a day for each and plan on accomplishing those tasks ahead of time, so you are entirely ready. Add another day if you plan on installing drywall over the insulation.