When installed properly, radiant barriers prevent 97% of the summer heat from penetrating through roof structures. They can also complement the performance of traditional thermal insulation in new construction. A radiant barrier can cut cooling costs by 5% to 10% in warm climates. That reduces the peak energy load and allows for a smaller air conditioning system. Visit https://www.ultimateradiantbarrier.com/ to learn more.
The reflectivity of a radiant barrier is its ability to refract thermal radiation from the sun. A commercial radiant barrier with a high reflectivity will reduce the radiant heat it absorbs and be more effective than a product with a lower reflectivity. The emissivity of the radiant obstacles is measured using an infrared camera and is a number between 0 and 1. The lower the emissivity of a material, the less it absorbs and emits. A radiant barrier should have an emissivity of about 0.03 to 0.05 percent, though some manufacturers make products with lower emissivities.
The primary reason that radiant barriers are often supplemented with traditional insulation is to prevent thermal transfer by conduction and convection. Radiant barriers prevent convection and conduction by converting radiant heat into a cooler form of thermal energy. To do this, they must have an air gap on at least one side of the material. That is the same principle that stainless insulated tumblers use to prevent heat from transferring through them. To ensure this air gap, some products, such as bubble foil insulation, require an air space between them and the sheathing or rafters. That is not recommended for attic installations, as it creates a space where moisture can settle and cause mold problems.
However, when used as a standalone product, a radiant barrier can elongate the life of HVAC equipment and ductwork and significantly reduce an attic’s temperature and, consequently, your energy bill. It also prevents the sun’s rays from heating your attic, which is especially beneficial in warmer climates.
While some companies claim to provide a specific R-value for their radiant barriers, they usually include other factors, such as the application method and building materials, when making this claim. If you need to satisfy a building code requiring a certain R-value, combining a radiant barrier with traditional insulation is necessary.
In a standard attic application, radiant barriers are placed on the attic floor with the foil facing up. Then, they are stapled to the bottom surfaces of the attic truss chords or rafters. While some radiant barriers are made with perforations, it is important to note that these holes only account for a small percentage of the total surface area of the material and will not negatively impact its performance.
Radiant barriers prevent radiant heat transfer by absorbing and reflecting the energy of UV rays. That keeps the air inside your home cool all day, just like a reflective sunshade does for your car windshield. If you’re comparing different radiant barriers, it’s important to know how they differ. Look at their emissivity rating. The lower the emissivity, the better.
The most common radiant barrier is made from foil laminated to a non-perforated substrate material, like kraft paper, plastic film, or oriented strand board. Some are fiber-reinforced to increase strength and durability. If you plan to install the product in an area with air movement (like an attic), choose a breathable radiant barrier. Some companies even market their products as “NASA certified.” While NASA did embrace radiant barriers, they did not certify any specific brands or manufacturers.
A radiant barrier is often installed before installing roof sheathing in new construction. The product’s roll is draped over the rafters in an attic, creating a small air space above the insulation. This air space allows convective heat to rise naturally and keep the insulated space from getting too warm. The insulating surface of the radiant barrier is then placed over it.
Some radiant barriers require the low emissivity surface of the product to face an open-air space to work properly. The insulating layer should not be sandwiched between solid surfaces. For example, suppose the radiant barrier is installed beneath trusses and roof decking, and you use a solid reflective foil laminate. In that case, it must be vented through the attic ceiling to function as an effective thermal barrier.
If a radiant barrier is installed in an existing home with closed walls, it can still reduce cooling costs and improve comfort by preventing the transfer of conductive heat through the walls. However, the insulating performance is unlikely to meet building codes, so it may not be worth the additional expense for most homeowners.
In addition, radiant barriers have a very different R-value than traditional cellulose or fiberglass insulation. The R-value of conventional insulation is based on the material’s ability to resist conductive and convective heat transfer. Most radiant barriers have a very high reflectivity but a very low emissivity and, therefore, do not satisfy the R-value requirements of most residential construction.
A radiant barrier has a reflective surface that prevents heat radiation transfer. Its low emittance reflects the sun’s radiant energy away from your home instead of absorbing and heating it. That reduces the energy your air conditioner needs, lowering homeowners’ utility bills. It also keeps your living space cool for longer, similar to how an insulated cup of coffee will stay warm and refreshing for a long time after pouring it.
Radiant barriers can be used alone or in combination with many types of insulation. They are typically made from shiny aluminum foil laminated to paper, plastic, or oriented strand board (OSB). Some radiant barriers have perforations that allow moisture vapor to pass through the material. This feature is important for homes with existing insulation since it can help prevent the build-up of moist air inside the attic.
The best radiant barrier materials should have a high moisture resistance rating. The material should also be resistant to the elements and abrasions. When selecting a radiant barrier, look for a product tested by an independent laboratory. The test results should be published on the manufacturer’s website. Those with higher ratings have greater resistance to moisture and other environmental contaminants.
Often, radiant barriers are included in energy-saving packages for new homes. These can consist of spray foam insulation or other measures marketed to help make the home more efficient. Builders should take the time to review all costs involved before purchasing a package deal. That can help minimize installation and supply costs.
A commercial radiant barrier can be installed under roof sheathing and over attic rafters or existing insulation. It is a great solution for reducing summer cooling costs and retaining indoor heat generated by furnaces in the winter.
When installing a radiant barrier, it is important to follow the manufacturer’s instructions and safety precautions. It’s also recommended to work with a professional installer. If you decide to install it, carefully study the manufacturer’s instructions and consult your local building codes for specific safety precautions. Contact a brilliant insulation trade association if you need help installing your radiant barrier properly. They can provide a list of qualified contractors and tips for proper installation.
Radiant barriers stop 97% of the summer heat from penetrating your attic by reflecting it to the outside. That keeps your attic cool, which cuts air conditioning costs and improves your home’s comfort level.
A radiant barrier is a reflective aluminum foil insulation applied to one or both sides of different substrate materials, including kraft paper, plastic films, cardboard, and oriented strand board (OSB). Some products are also reinforced to increase durability.
In the construction industry, sheathing with radiant barrier is popular in new homes and re-insulation projects where a vapor barrier is needed. A sheathing product with a radiant barrier laminated to both sides of an OSB substrate is required for superior performance and longevity.
Another popular choice is radiant barrier sheets installed under or on top of existing attic insulation. Both methods have advantages and benefits but must be installed correctly to achieve their full potential.
When stapled up, a radiant barrier prevents summer heat from entering your attic, which keeps your attic and the rest of your home cooler and saves energy. The key is to ensure the foil isn’t sandwiched between joists because this creates an area of conduction that transfers heat INTO your attic.
If you install a radiant barrier under your insulation, ensure it does not touch the roof decking and cut openings in the foil over existing attic vents to allow for attic ventilation. It’s a good idea to cover any gable end walls as well.
When stapling a radiant barrier under your attic insulation, it’s best to use a cordless staple gun. It’s a lot easier on your wrist and helps ensure the staples go through the foil. It’s also a good idea to stock up on staples because going through a box of 1,250 for every 1,000 square feet you install is not uncommon. Investing in the right tools and supplies makes the job quicker, easier, and more effective. You’ll also want to ensure your attic is moisture-free, which can lead to mold and mildew.