How Can I Insulate My Garage Without Drywall?

Perhaps you want to convert part of your garage into a gym or workshop, or you want to hang out there after work. Maybe the cold from the garage is pushing up your home’s energy bills. Either way, you want to insulate your garage to keep it from getting too hot in the summer and too cold during winters.

Here’s how to insulate your garage without drywall:

  1. Consider whether you can insulate without drywall.
  2. Check your local regulations regarding drywall installation.
  3. Consider the costs of drywall installation.
  4. Consider the materials you need for drywall installation.
  5. Choose your insulation material.
  6. Install your insulation material.
  7. Seal your external walls.
  8. Insulate the doors and ceiling.
  9. Give your interior walls the right finish.

How Can I Insulate My Garage Without Drywall_

The remainder of this article will outline the steps involved in insulating your garage if it doesn’t have drywall installed. I will discuss the considerations for when you should insulate with drywall or not and the steps you need to take to do so (if it’s required).

* This article may contain affiliate links. As an Amazon Associate, I earn from qualifying purchases.

1. Consider Whether You Can Insulate Without Drywall

Ordinarily, you install insulation behind drywall.

It fills the space between the drywall and wall frame that doesn’t have plumbing, electrical wiring, or other structural elements.

This way, your walls stay insulated and have the best finish possible.

2. Check Your Local Regulations Regarding Drywall Installation

While drywall (or alternatives like plaster or wood paneling) is essential for the interior walls of your home, not all garages need to have drywall installed.

Depending on local regulations, homeowners may not be required to install drywall in garage walls that don’t share common walls with their homes.

3. Consider the Costs of Drywall Installation

Alternately, homeowners may choose not to install drywall in their garage to save money.

Or they may have bought a house with an existing unfinished garage.

Under these circumstances, homeowners may install insulation without putting in drywall.

Installing insulation without drywall gives you all the insulation benefits without the added costs of installing drywall.

4. Consider the Materials You Need for Drywall Installation

An exposed wall frame makes it easier to install insulation for several reasons.

To begin with, you won’t need to do the added work of removing existing drywall to put in insulation.

You can also choose to work with batts, rolls, or blocks of insulation material and largely avoid using sprayed foam or loose-fill insulation materials in the installation process.

Batts, rolls, and blocks are easier to work with than loose-fill or sprayed-foam insulation.

Sprayed foam and loose-fill insulation materials usually require more specialized equipment to use.

They also demand more precision in installation. Improper installation can adversely affect insulation and lead to higher energy costs.

The most notable drawback of eschewing drywall is that your walls won’t have as neat a finish.

5. Choose Your Insulation Material

Materials you can use for home insulation include fiberglass, foam, foil, and concrete.

When choosing between these materials, you need to account for your specific insulation needs and how skilled you are when handling said materials.


Fiberglass is the most common material in DIY projects since it’s relatively cheap and easy to use.

It comes in pre-cut batts, rolls (that you can cut to size), and loose-fill forms.

Its main drawbacks are vulnerability to moisture and fire.


Materials like polystyrene and polyurethane are also common in home insulation.

They can be rigid boards, rigid blocks, or spray-in foam.

Foam insulation is highly efficient and offers good noise reduction.

However, foam insulation can be expensive and complicated to install.

It can also be vulnerable to pests and restrict ventilation.


Reflective foils offer significant insulation and noise reduction capabilities.

However, these are expensive to use throughout and mainly used for doors, ceilings, and other hard-to-work areas.

They’re also not as durable as the other materials listed so far.


Concrete blocks offer high thermal resistance when used in insulation.

They’re also very sturdy, as you can build them into your house’s walls.

However, concrete blocks can be challenging to use.

They’re heavy, take up significant storage space, and are difficult to mold.

6. Install Your Insulation Material

Once you’ve chosen the specific material you’ll use, the installation process is straightforward.

Cut the insulation material to the appropriate size and fit it into the gaps between your wall studs.

As I’ll outline in the next section, it would help if you also took measures to ensure your installation goes smoothly.

7. Seal Your External Walls

Before you put in your insulation, inspect the exterior walls of your garage to make sure there are no cracks, gaps, or other openings in it.

Such openings can allow moisture and pests entry into your wall and reduce the thermal efficiency of your insulation.

I recommend using a waterproof sealant, like the Red Devil Acrylic Sealant (available on, to seal all breaches to the external walls of your garage.

The Red Devil Acrylic Sealant works well with tough materials like concrete and won’t leave stains.

8. Insulate the Doors and Ceiling

It’s not enough to insulate only the walls of your garage.

A poorly insulated roof or door can lead to a significant loss of thermal efficiency in your home.

Garage doors and ceilings don’t have wall frames, and securing insulation can be tricky.

Adhesive pins and sheets of foil insulation are good choices in these cases.

9. Give Your Interior Walls the Right Finish

Since your garage doesn’t have drywall, you’ll need to work on its finish.

You can use the papered side of a fiberglass insulation sheet on the inside to give your garage a smoother finish.

If working with concrete, paint over the blocks. Also, use a vapor barrier to protect your walls from moisture.

Final Thoughts

Even without drywall, it’s possible to insulate your garage using various materials.

These include fiberglass, foam, foil, and concrete.

The most common material used in home insulation is fiberglass.

It’s cheap, easy to use, and effective.

You’ll also need to take a few additional measures to ensure that your garage is effectively insulated.

You’ll need to insulate your garage’s ceiling and doors, not just its walls.

You’ll also need to finish its interior walls appropriately and seal its exterior walls.

Cheers, tools owners!

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Hi there! My name is Jack and I write for ToolsOwner. I have a passion for everything related to tools and DIY projects around the house. You often find me in my workshop working on new projects.