How to Insulate a Garage Ceiling

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Insulation is crucial if you live in a colder climate and want to use your garage as an extra living space. The garage ceiling is one of the most important places to insulate, as it is where most of the heat will escape.

There are a few different ways to insulate a garage ceiling. One way is to install insulation panels directly to the ceiling. Another way is to install a suspended ceiling system and then attach the insulation panels to that.

No matter what method you choose, be sure to use high-quality insulation products that will keep the heat in. You may also want to consider using a thermal barrier, such as foil insulation, to help further reduce heat loss.

In this article, we will discuss the different methods of insulating a garage ceiling. We will also provide tips on choosing the right insulation products and installing them correctly.

Why Should You Insulate Your Garage Ceiling?

garage ceiling insulation
How to Insulate a Garage Ceiling

If you’re planning to install an air conditioner or heater in your garage, you’ll need to insulate the ceiling. Otherwise, the heat or cold will escape through the attic, and you’ll end up wasting energy and money.

Another reason is that heat rises and if your garage is attached to your house, the heat from the garage will rise into your house in the winter. This can cause your furnace to work harder and increase your energy bill while still leaving you with a cold garage.

Not only is garage ceiling insulation good at keeping the right temperature you want to work in your garage but it helps to block moisture and pests and noise that garage door openers or you busy on your next project make. This way you stop bothering your family members or neighbors and keep the pests out of your garage from chewing on your treasured items.

Also Read: Best Garage Door Insulation

Types of Insulation Material for Garage Ceilings

There are two main types of insulation material: fiberglass and spray foam.

Fiberglass Batts or Rolls

Fiberglass Chopped Strand Mat 1.5 oz | 50 inches Wide x 60 Feet Long | 20 Yards Rolled | Hand Layup, Vacuum Bagging, Polyester or Vinyl Ester Resins

Fiberglass is the most common type of insulation. It comes in batts or rolls, and you install it by pressing it into the spaces between the joists in the attic. It’s a good choice for garage ceilings because it’s cheap and easy to install.

It comes with an R value which is a measure of how well it insulates. The higher the R value, the better the insulation. For ceilings, you want an R value of at least R-30.

Blown in Loose Fill Fiberglass or Celulose

Fairfield PF-5 Poly-Fil Premium Fiber , White

On the other hand, blown in insulation is a better choice for garages that have cathedral ceilings or are irregularly shaped. This type of insulation is installed by blowing it into the spaces between the rafters or trusses.

The materials normally used are fiberglass or cellulose. Cellulose is made from recycled paper, so it’s environmentally friendly. Loose fill fiberglass is a better choice than cellulose if you have allergies because cellulose can contain dust particles.

Things You’ll Need for Garage Ceiling Insulation

You will need the following items to install insulation in your garage ceiling:

  • Insulation materials
  • Expanding Foam
  • Ladder or scaffolding
  • Box cutter knife for cutting insulation
  • Staple gun for attaching facing and vapor barrier to ceiling joists
  • Measuring tape
  • Safety glasses, long sleeve shirts, gloves, pants, and a dust mask. 

How to Insulate a Garage Ceiling: Step by Step Guide

Here’s a step-by-step guide for insulating your garage ceiling:

Step 1: Seal Gaps and Holes With Expanding Foam

First, you will need to do some preparation work. Inspect the garage ceiling for any gaps or holes and seal them with expanding foam. This will help to keep the insulation in place and prevent drafts. Don’t fill any vents under your roof that are intended to assist with air circulation.

Step 2: Install Baffles for Ventilation

Next, install baffles for ventilation. These are strips of wood or metal that you can buy at home improvement stores. They’re installed between the rafters or trusses to create air spaces, which allow the insulation to work properly. If your roof does not allow for adequate ventilation, moisture will accumulate and mold may grow.

Step 3: Do You Have a Finished or Unfinished Ceiling? 

If your garage ceiling is still unfinished and you have exposed joists, there are a few things you can do. You may install batt or roll insulation from the bottom and then cover it with drywall or you can put drywall down after that and use blown-in loose fill insulation or bat insulation for further thermal comfort.

If the garage ceiling is already done then the top will require insulation. This entails going into the attic and filling it with loose fill or putting in batt and roll insulation.

If you have a garage above a room, the builder may or may not have insulated the ceiling to cut corners. If the garage ceiling is covered and there is a room above it with flooring, you’ll have to decide whether to remove the flooring or the garage ceiling in order to improve insulation.

Step 4: Install Batting or Rolls From the Bottom 

Now, choose the insulation type you want to use. If you’re using batt or roll insulation, cut the correct size and install it from the bottom of the garage ceiling. Make sure to staple it in place so that it doesn’t move. 

Watch out for electrical wiring and plumbing pipes when you’re installing insulation. You don’t want to cover them up or damage them with staples. Make sure you’re following the codes set by your municipality.

Step 5: Install Batting or Rolls From the Top of a Finished Ceiling

However, if you’re attempting to install insulation in a finished garage ceiling, you’ll need to go into the attic and do it from there. This is a more difficult process and should only be attempted by those who are experienced.

Step 6: Install Loose Fill Fiberglass or Cellulose

If you’re using loose fill insulation or cellulose, cut a hole in the ceiling and blow it in with a special machine. Make sure to wear safety glasses, a dust mask, and gloves while you’re doing this.

Safety Precautions for DIY Garage Ceiling Insulation

GVS SPR457 Elipse P100 Dust Half Mask Respirator with replaceable and reusable filters included, blue, m/l size

It is absolutely vital that you take safety precautions when you’re installing insulation in your garage ceiling. Wear long sleeves, pants, gloves, and a dust mask to protect yourself from the dust and fibers in the insulation. If you have allergies, be sure to use cellulose insulation, because cellulose can contain dust particles. 

Make sure that you’re using the correct type of ladder or scaffolding when you’re working on high areas, and always have someone else with you in case of an emergency. Finally, never cover up electrical wiring or plumbing pipes while you’re installing insulation – it’s very dangerous!

How Much Does It Cost to Insulate a Garage Ceiling?

The costs vary greatly because of the variables involved such as the amount of insulation needed, the accessibility of the space, and the type of insulation used. Generally, it costs between $0.50 and $2.00 per square foot to install insulation. However, if you have to remove drywall or flooring, that will add to the cost. 


So, in summary, there are a few things you need to do if you want to insulate your garage ceiling. You can either install batting or rolls of insulation from the bottom or the top, or you can use loose fill fiberglass or cellulose. Whichever method you choose, be sure to take safety precautions and follow the codes set by your municipality. The cost of insulation will vary depending on the type and amount needed, so be sure to budget accordingly. Thanks for reading!

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