How to Insulate a Carport Roof

closeup of a Rooftop
  • 6-10 hours
  • Intermediate
  • 100-700
What You'll Need
Safety goggles
Dust mask
Insulation (fiberglass)
Sharp utility knife
Staple gun and staples
One sheet of plywood (1/2 inch)

A carport, like an attic, needs to be properly insulated. If these areas are improperly insulated a lot of energy is wasted. Proper insulation keeps the house warm in the winter and cools in the summer. Insulation controls condensation which in turn helps to avoid build-up of harmful mold and it reduces corrosion in metals. Insulation also controls noise and the better insulated the room is, the less likely for noise to come through.

There are 3 types of insulation that can be used for your carport, attics or metal buildings. These are fiberglass, reflective insulation and foam board. Fiberglass is a material made from very fine fibers of glass, therefore its name. Foam boards can be used to insulate most parts of your home from the roof of the house to the foundation because they provide good thermal resistance and add structural strength to a home. Materials used in making foam boards are usually, polystyrene, polyisocyanurate or polyurethane. Reflective insulation is also known as a radiant barrier and is made of an aluminum foil that's designed to block heat transfer across open spaces and is most effective in hot climates.

Step 1 - Determine the Size of Your Roof

Measure your carport’s roof or ceiling, its length and its width to get the measurements of the insulation that you are going to need. Make sure to take the necessary precaution and wear a face mask or protective goggles, a dust mask, gloves, and a hat. This is to protect you from the fiberglass insulation because it can get into your skin, eyes, and lungs and cause serious irritation. It is also not a good idea to start this project on a hot day. Opt for cooler weather when you attempt to install insulation of any kind.

Step 2 - Keep Materials Away from Heat Producing Systems

Insulation materials are highly flammable. It is important you keep yourself and the insulation materials at least 3 feet away from any heat-producing mechanisms.

Step 3 - Place the Plywood and Insulation

You need someone to help you with this step, put the plywood over the ceiling joists and ask someone to lay out the rolls of insulation for you. The plywood works as a walking platform. Begin at the ends of the ceiling and work your way toward the center of the room. Remember that the paper facing of the fiberglass should be installed facing up. Firmly press the insulation into the joist bays and once you have reached the end of the joist bay you can cut the ends off with a utility knife or any sharp knife.

Step 4 - Staple Insulation in Place

Once you are satisfied with the placement of fiberglass insulation, you can now use and load the staple gun with staples and staple the fiberglass insulation in place. Make the staples at least 5 inches apart from each other. Be careful not to crush the insulation too much. The depth is part of what lets it work.

Step 5 - Stuff Tight Areas

Use the leftover pieces of insulation to stuff into tight areas. You can use a broom handle to reach into tight spots.

If you are satisfied with how much insulation you have put on your carport’s roof then you are done, just make sure everything is in its place. Sometimes some ceilings or roofs need two layers of insulation if you feel that you need to add more layers, just make sure that the second layer is at a 90-degree angle to the first layer.

PRO TIP: Removing Fiberglass From Exposed Skin

Do not get under cold water or take a bath. It's tempting in the heat of Summer to want to chill out with a cold shower, but cold water will cause your pores to close and the glass fibers to get trapped in them. They will drive you bonkers from itching for a week. Start with lukewarm water and rinse yourself off really well for 3-5 minutes

Do not touch anything to your body with your hands, or with a face cloth as it is all over your hands and it will ruin the face cloth while rubbing fiberglass into and underneath your skin. Gradually increase the hot water until it's as hot as you can stand it and soak under the hot shower for 3-5 minutes. Preferably 5. This allows the fibers to wash out of the pores many are already trapped in.

Do not touch yourself at any time during the rinse cycle. After 3-5 minutes you can bring the temperature of the water down to cool or cold as you prefer and close your pores. Then you can wash yourself off with soap and whatever else you might use. It's best to use nothing but your hands and liquid soap if possible so that no residual glass fibers get into re-opened pores, your favorite loofah, or the soap itself.