How To Install Radiant Barrier Roof Sheathing

Proper insulation in your home will provide adequate conditioning throughout the year. The roof is no exception, and it is imperative to give it as much attention as the rest of the home. Bearing that in mind, what is the best insulation for your roof if you live in a hot climate? What insulation can you install in your roof to keep your home cool during summer? We have the following answers for you after consulting the experts.

Radiant barrier insulation is one of the ways to insulate the roof of your home to keep it cool. You can insulate your roof  by installing a radiant barrier in the following ways:

  • Installing radiant barrier on top of roof truss but under the roof sheathing
  • Installing radiant barrier below the roof rafters

Read ahead to learn how to install radiant barrier insulation on your roof, and become familiar with the benefits of this type of insulation and the costs for installation.

Man installing radiant barrier on the roof, How To Install Radiant Barrier Roof Sheathing

How Do You Install Radiant Barrier On Your Roof?

Having a radiant barrier insulation on your roof is an excellent way to keep heat away during summer and prevent heat from escaping during winter.

The barrier works by reflecting back heat from the sun's rays. It blocks the heat from passing through the roof and therefore does not reach into the rooms below.

An attic insulation is being installed in new homes

As you insulate as much of your roof as possible, ensure that you do not block any ventilation openings such as the soffit vents.

Let's look at two methods of how to install radiant barrier on your roof:

Installing Radiant Barrier On Top Of Roof Truss But Under The Roof Sheathing

This method is excellent for new homes under construction when the rafters are easily accessible before placing the roof sheathing on top. It’s, however, not viable for an existing home unless you do not mind the extra costs that come with it because you would have to remove the roof to install the radiant barrier and then reaffix the roof.

A simple way of installing a radiant barrier during construction is by fixing a board panel that has an aluminum layer on one side on top of the roof rafters. The aluminum side should face down into the house.

Follow the instructions on the manual and install all the panels on the roof, ensuring they are properly secured. Afterward lay the shingle underlayment, followed by the shingles.

Since this is a relatively complex job, you may need to call a certified professional, especially if you do not have the relevant skills. However, if you have the skills and would like to install it on your own, be sure to carefully follow the instructions in the manual.

Below is a video that explains how to install a radiant barrier panel with an aluminum layer on a roof under construction:

Installing Radiant Barrier Below The Roof Rafters

This is a radiant barrier insulation that blocks 95% of radiant heat, see it on Amazon.

For an existing home, the best option for installing a radiant barrier is stapling it under the roof rafters or under the chord below the roof rafters. This is an easy DIY project that you can tackle, especially in the attic. The basic tools you need are stapler gun, staples, and a cutter knife.

This is a heavy-duty stapler that you can use to staple radiant barrier insulation on your roof; see it on Amazon.

Begin by measuring the area to be insulated, purchase the required amount of aluminum foil, and then install it as explained in the video below:

Over The Ceiling Or Attic Floor Insulation

In addition to insulating below the rafters, you can insulate the floor of your attic if it is unfinished to maximize the comfort in your home. However, be extra careful since the floor is not very stable as it acts as the ceiling in the rooms below.

Measure the length and width of the floor to guide you on the right size of aluminum foil to purchase, and carry out the job as instructed below:

Items needed:

  • Radiant barrier sheet
  • Staple gun
  • Staples
  • Measuring tape
  • Foil tape
  • Straight edge
  • Scissors
  • Sharpie marker


  1. After measuring your attic floor, add an extra one foot to the measurements of the radiant barrier sheet and then cut it.
  2. Start from the farthest corner, rolling out the barrier as you lay it on the floor, which might have existing insulation.
  3. As you insulate, join the pieces of the radiant barrier using foil tape.
  4. Cover the fixed obstacles such as pipes or timber with the insulation.
  5. Continue with this process until the whole floor is insulated.

Precautionary Measures When Installing Radiant Barrier On Your Roof

As with any other installation project, one should be careful to avoid any imminent injuries while working. For your safety, below are a few tips on the precautions to observe:

View of personal safety workwear

  • Wear appropriate clothing, such as work overalls, headgear, gloves, masks, and eye goggles. A fall arrest system will go a long way in protecting you in case of a fall while working on the roof. Don’t take any chances, no matter how confident you are.
  • Watch your head, especially when working in an attic with a pitched roof. Sometimes, nails penetrate through the underside of the rafters and can seriously injure your head.
  • When installing the barrier on an attic roof, be aware of where the electrical wiring is so that you do not staple over it. Check the attic and repair faulty wiring or replace it altogether early enough before you begin insulation.
  • Work with a partner who can help you when a problem arises.
  • It’s preferable to work early in the day when it is the coolest.
  • Have plenty of water to drink during the project.
  • For attics, ensure there is enough ventilation, making sure that you do not block any.
  • For unfinished attics, watch where you walk to avoid falling through the ceiling.

Is It Worth Installing Radiant Barrier On Your Roof?

Ventilation pipes in silver insulation material on the attic

Yes, it is worth it. It will condition your home, keeping it warm in winter and cool in summer. A radiant barrier improves the overall energy efficiency of your home, making it more comfortable.

Let us explore other benefits of radiant barrier insulation on your roof:

Save On Energy Bills

Because heat is turned away by the radiant barrier, the air conditioning system does not have to work so hard to either cool or warm your home.

Prevents Build-Up Of Moisture

As the radiant barrier reflects away heat, moisture does not have a chance to settle on it. Besides, some are perforated to allow air to flow, preventing the formation of moisture.


With time, most traditional insulation will deteriorate. In contrast, the radiant barrier does not settle and will not degrade, and neither can pests chew on it. It will continue functioning well for a long time, saving you on replacement costs.

Can Be Added On Top Of Current Insulation

Even with existing insulation, a radiant barrier can be added on top to improve the overall thermal efficiency of your home.

How Much Does It Cost To Install Radiant Barrier on the Roof?

Wooden cubes foorming word COST and calculator

The cost of radiant barrier installation on your roof will depend on the climate of your area, the complexity of the job, and the amount of material to be used, amongst other factors.

To insulate a 1,500 square foot in the attic, would cost between $710 and $2,840. The cost of materials can be as low as $ 0.1 and as high as $0.95 per square foot.

A professional would charge you between $30 and $80 per hour to install a radiant barrier. An experienced professional might charge you more.

These costs are estimates and might be higher or lower than is explained here.

In Closing

Installing a radiant barrier on your roof will improve the overall conditioning of your home, thereby reducing the energy bills. With several methods to insulate your roof, identify the most suitable for your home, which largely depends on the climate in your area.

The insulation is relatively easy to install, but it is better to allow a professional to handle the job if it is a complicated one or you do not have the necessary skills.

Can you paint radiant barrier insulation, and does it block your Wi-Fi or phone connection? Read our previous posts and learn more by clicking the links below:

Does Radiant Barrier Block Reception?

Can You Paint Foil Insulation And How To?


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