Go Green - Energy Efficiency in Your Home

Radiant barriers have been around for decades, and in the last few years savvy homeowners have discovered two related benefits of installing Energy Star radiant barrier. The two major benefits of installing reflective radiant barrier include maintaining a more consistent indoor temperature, which leads to the second benefit of, reduced energy costs.

The main reason energy costs are reduced is because your home's air conditioning unit will run more efficiently and less frequently throughout the hot summer days. And in hot climates like Texas, Arizona, California, Florida, Alabama, Georgia and many other southern states, a reflective radiant barrier like Enerflex can help you reduce your utility bill by as much as 30%. But, it is very important that your attic has the recommended insulation installed for your region and adequate ventilation for the heat to escape back outside.

In the winter, Enerflex Radiant Barrier will help reduce indoor heat loss that comes up through your ceiling. The same principle is applied – the amount of energy / heat moving up toward the radiant barrier is reflected back into your attic and down into your home.

Installing an approved radiant barrier in certain applications may qualify for state and local government tax credits. Many energy companies also offer rebates to their customers for installing an attic radiant barrier. Look for programs in your area to take advantage of these savings.

See more information and videos on energy efficiency and radiant barriers in my "Go Green" blog.

Installing Enerflex radiant foil barrier is an easy do-it-yourself project that will help reduce the temperature in your home during the summer and help keep heat in during the cooler months. Combined, Enerflex will help reduce your heating and cooling bills throughout the year. What's more, this Energy Star certified radiant barrier qualifies for a tax credit up to $500.

Enerflex Radiant Barrier can be purchased at select Home Depot locations or by special order on The Home Depot website. You can also purchase Enerflex from your local building material dealer. To find the nearest dealer, go to the How To Buy page on Enerflex website.

Simply put, no. In order for a product (paint, foil or metallic film) to be classified as a radiant barrier, defined by ASTM, the product must produce at least 90% reflectivity. The Reflective Insulation Manufacturers Association (RIMA) says the reflectivity of "radiant barrier paints" range from 10% to 75%, which will provide drastically different results compared to the best radiant barrier insulation. In fact, the application of a ceramic radiant barrier paint to the underside of roof is not an easy do-it-yourself project as the fumes are noxious (VOC respirator needed). If a paint does not conform to ASTM C 1321, "Standard Practice for Installation and Use of Interior Radiation Control Coating Systems in Building Systems", it should not be considered for interior applications in the attic.

In addition, before you consider purchasing reflective paint or a reflective metal barrier, make sure it is Energy Star certified and has a Class A fire rating. Typically any Energy Star qualifying product will have a corresponding label/logo on the packaging.

Energy Star certified Enerflex Radiant Barrier is a metalized film that has a class A/1 rating for fire and smoke. It also meets the new mounting requirements for ASTM – E84 under E2599. ASTM E2599 is the new industry standard which will be reflected in the 2012 building codes. ASTM standards are adopted by organization such as IECC, IBC, IRC, and ICC.

See how easy it is to install Enerflex in this short video.

Saving money around the house continues to be a major pursuit for homeowners nationwide. And with a focus on “going green”, savvy homeowners are looking for ways to cut energy use to reduce utility bills and their home’s carbon footprint.

There are dozens of ways to curb energy use around the home. Sealing drafts by applying caulk and weather-stripping around windows and doors, and applying foam sealer around drafty outlets and piping leading outside can save up to 5 percent on heating costs alone. Most important, installing the proper amount of attic insulation with the proper airflow is generally the best way to save on home energy use.

If you are among the millions of Americans who enjoy do-it-yourself home improvement projects, installing a radiant barrier in the attic space above your home is one of the most effective energy-saving projects to consider.

While radiant barriers are not a new concept, new products on the market are making it easier for homeowners to install them and realize reductions in their energy bills—every month. Overall, a radiant barrier can save an average homeowner up to 15 percent on utility bills.

Rick Jordan of EcoRite Products, a major radiant barrier manufacturer, says the benefits of installing a radiant barrier have long been known by professionals in the construction, roofing, heating and cooling, and energy industries. Only recently have products been manufactured specifically for the DIY installer market.

Jordan explains that a radiant barrier is a product that is installed in the attic—between the rafters on the underside of a roof—to reduce the radiant heat gain that permeates a home when the sun is beating down on it. Radiant barrier, a particularly effective product for summer months, also reduces heat loss from a roof during the winter, which in turn reduces the workload on your furnace and lowers your heating bill.

Early, less-effective versions of radiant barriers included spray-on metallic paints, reflective radiant barrier chips or products known simply as attic foil. Installation was cumbersome, often requiring special tools, adhesives or multiple installers, and the low flash point on the older type of foil created added dangers in the event of a house fire.

It’s important to choose the best radiant barrier that is Energy Star approved and made of metalized film, not perforated aluminum foil. Today’s radiant barriers are far more sophisticated, yet some are so simple to install that no tools are required.

About Enerflex Radiant Barrier
Enerflex Radiant Barrier is an example of the best new radiant barrier technology. The product is available nationwide through a network of lumber and building materials dealers, as well as through major retailers. The product is Energy Star approved and was named one of the “Best New Products of 2010” by Professional Remodeler, a leading trade magazine.

Enerflex Radiant Barrier comes in rolls or panels, pre-cut for 16” and 24” widths for installation ease. The radiant barrier panels literally flex or “snap” into place between the rafters, with no tools needed. This makes it possible for installation to be a simple, one-person, do-it-yourself job that can be completed in a matter of hours. Watch a video on installing Enerflex radiant barrier.

Studies on installed radiant barrier products show that attic temperatures are typically reduced by a full 30 percent during the summer months, which can translate to 30 degrees on a hot summer day. In addition, the radiant barrier keeps heat from escaping from the home through the roof during the winter, so not only does your HVAC system get a break, but you can realize energy savings year-round.

Unlike the earlier versions of radiant foil barriers, Enerflex is made of a highly reflective, multilayered, metallic film that is protected by a tough poly scrim that keeps it from tearing or being punctured. The product is made in America, comes with a 15-year warranty, and has achieved a Class A/Class 1 fire rating.

In really hot climates, homeowners are finding other uses for radiant barriers. In Texas and Arizona, for example, many homeowners keep garages cool by installing radiant barrier insulation on the inside of garage doors and walls. Outbuildings on farms or ranches, or outdoor workshops can also be kept cooler in the summer when the product is installed between rafters under the roof.

Jordan of EcoRite Products says adding a radiant barrier in the cooler months makes installation safe and more comfortable for the installer.

Radiant barriers are proven environmentally friendly building materials for reducing energy bills and reducing the strain on a home’s HVAC system. And when you can spend a few hours over a weekend and complete a project that saves money month after month, it’s hard to ignore the benefits.

We’ve mentioned that it’s easy to install Enerflex radiant barrier in an attic, haven’t we? To make sure we’re doing our job by making it easier for you to do yours, we’ve created a step-by-step how-to video.

You’ll see just how easily and quickly Enerflex radiant foil barrier will help you lower the heat level in your attic. Enerflex blocks up to 96 percent of radiant energy and could decrease your attic temperature by up to 30 degrees. That equates to big time savings on your utility bills!

In short, R-value is the accepted way of measuring the effectiveness of insulation (resistance to heat transfer via convection and conduction). And it’s important to note that the majority of the energy lost in a home is through emission or radiant heat transfer.

E-value measures the ability to prevent heat transfer via radiant emission. And since radiant emission is by far the major factor of energy loss in your home, E-value (the ability to stop radiant heat transfer) is really more important than R-value in determining the effectiveness of your attic insulation. 

Energy Star approved Enerflex Radiant Barrier (made of metalized film) has a much higher E-value than any type of fiberglass insulation and can help reduce energy costs dramatically, especially in the hottest climates like California, Texas, Georgia and other southern states.

If you’re remodeling an older home, there are many options for updating with green principles in mind. Indoor air quality, water conservation and sustainable building products are considerations when planning an environmentally friendly home. If you’re looking for the biggest bottom-line and long-term effect, let reduced energy consumption lead the way for your remodel.

In warmer months, air conditioning is a leading cause of increased utility bills. In hot weather, roof shingles absorb the sun’s heat—which in turn heats up the sheathing below and radiates heat toward the floor or the attic. To reflect up to 96 percent of this radiant energy back toward the roof, install Enerflex Radiant Barrier.

A Centex Corporation and Energy Center of Appalachian State University study has determined that when radiant barriers are installed in an attic, the air conditioning system works more efficiently and electric bills decrease. The study found that when radiant barrier was installed in test homes, there was a drop of 23 degrees Fahrenheit in the attic’s peak temperature, a 20 percent reduction in operating time of the air conditioning system during seven hours of peak attic temperatures, and an efficiency improvement of 57 percent for cooled air coming through a home’s air ducts.

Energy Star approved Enerflex Radiant Barrier’s simple, between-rafters tension fit allows easy, tool-free installation. And Enerflex is great for existing homes. Watch our step-by-step “how to” video and see how easy it is to install Enerflex Radiant Barrier.

Years ago I used to work at a restaurant and when we baked our potatoes we wrapped them in aluminum foil to keep them warm longer. Well, the same concept works in your home’s attic. Just like wrapping a baked potato in aluminum foil keeps a potato warm longer, installing Enerflex radiant barrier in your attic will help retain the heat in your home.

An ENERGY STAR approved radiant barrier will help reduce the heat you would typically loose when it’s cold outside, which helps you save on your heating bill. The next time you have to crank up the heat in the winter, think of your home as a giant potato. Keep it warm and install Enerflex radiant foil barrier.

When the sun heats a roof, it's primarily the sun's radiant energy that makes the roof hot. A large portion of this heat travels by conduction through the roofing materials to the attic side of the roof. The hot roof material then radiates its gained heat energy onto the cooler attic surfaces, including the air ducts and the attic floor. Radiant barrier / radiant foil barrier insulation reduces the radiant heat transfer from the underside of the roof to the other surfaces in the attic.

A radiant barrier's performance is determined by three factors:

1. Emissivity (or emittance) – the ratio of the radiant energy (heat) leaving (being emitted by) a surface to that of a black body at the same temperature and with the same area. It's expressed as a number a between 0 and 1. The higher the number, the greater the emitted radiation.
2. Reflectivity (or reflectance) – a measure of how much radiant heat is reflected by a material. It's also expressed as a number between 0 and 1 (sometimes it is given as a percentage between 0 and 100%). The higher the number, the greater the reflectivity.
3. The angle the incident radiation strikes the surface—a right angle (perpendicular) usually works best.

Five key benefits of installing a radiant barrier

1. Reduced heating and cooling costs (lower utility bills) 
2. Increased comfort levels
3. Increases building's energy efficiency 
4. Keeps heat out during the summer
5. Keeps heat in during the winter

We’ll, to be vague, often. Replacing your furnace filter really depends on your home’s environment. Do you have pets? Do you keep your windows open? Many more questions can be asked. But in short, check your furnace filter monthly to see if it’s collecting dust and particles. I typically change my furnace filter out when the filter starts turning gray. And that’s typically prior to the three-month filter replacement period many homeowners try to abide by.

Replacing your furnace filters often will not only save you money but will also protect your health by maintaining good air quality in your home. A furnace filters job is to help circulate clean air and to capture irritants like pollen. If your filter is too dirty the air struggles to pass through it and will make your furnace work harder. It’s important to change your filter often to prevent damage, costly repairs and to maintain your furnace so that it’s not overworked. Changing your furnace filter regularly can help reduce your heating bills.

And if high heating bills are an issue, consider installing a radiant barrier product in your attic. During the cold season when your furnace is forcing hot air through the home, radiant barrier insulation will help keep the heat from escaping through the roof. Adding radiant foil barrier will help reduce the load on your furnace.

2009 case study findings at the Energy Center at Appalachian State University showed a 20 percent reduction in an air conditioner unit's run time during seven hours of peak attic temperature. This study also indicated that the installation of a radiant barrier in an attic can make it easier for your air conditioner to do its job in the summer heat. That translates to lower electricity usage, which also impacts the carbon footprint of homes and will help reduce your utility bill.  See the complete study.

Some radiant barriers, like Enerflex, are easy to install, in both new construction or during renovation of older homes. Radiant barrier foil is used in addition to insulation, as the reflective nature of a reflective foil barrier will help reduce the movement of radiant energy—which accounts for most of the heat gain in buildings.

Key findings of the radiant barrier study include:

• A 23-degree drop in the peak attic temperature occurred in a home outfitted with radiant heat barrier versus a similar home without the barrier;
•  A 20 percent reduction in the run-time of the air conditioning unit during the seven hours of peak attic temperatures; and
• The radiant barrier improved the efficiency of cooled air delivered through the air ducts by 57 percent during this period.

Enerflex Radiant Barrier qualifies for the American Recovery Tax Credit for insulation—equating to savings of 30 percent, up to $1,500. Enerflex is also ENERGY STAR® approved and allows specifiers to earn up to five LEED points under EA 1 and MR 5. Installing Enerflex in certain applications may qualify for state and local government tax credits.

There is some controversy as to whether radiant barrier insulation reduces the life of asphalt shingles. Studies by both the University of Florida and Texas A & M University show no significant heat increase in shingles on roofs employing radiant barrier insulation in conjunction with full venting. 

Texas A&M University actually built two homes to test the effectiveness of radiant foil barrier insulation. One home without radiant barrier and one with radiant barrier. The tests concluded that there was a significant reduction in heat gain in the test home with radiant barrier insulation. There was no evidence of damage to shingles because of reflected heat.

Here are the results of the Texas A&M University Radiant Barrier Study (PDF). This study should alleviate fears about using radiant barrier foil on a home that has asphalt shingles. As long as you use full venting—that is a full ridge vent and vents along the soffit—it is OK.

Further studies at Texas Tech University have shown the cooling effect in a hot attic of radiant barrier insulation to be approximately 15 degrees with an asphalt shingle roof and 13 degrees Fahrenheit with a metal roof. How this translates into a certain percentage of cost reduction depends on the amount of insulation between the dwelling and the attic.

There are new underlayment products that go directly under a metal roof but for existing homes your choice will be limited to stapling the proper width of radiant barrier between your rafters up against the ceiling.

Radiant barrier insulation is among our list of green building products. It appears that it does live up to most of the manufacturer's claims. Here's an in-depth explanation of how radiant barrier insulation works by the U.S. Department Of Energy: DOE Radiant Barrier Information.

Professional Remodeler Magazine, a leading business to business remodeling trade publication, has selected Enerflex Radiant Barrier, by Universal Forest products, as one of the best new products for 2010. The 101 Best New Products is an editor's choice award; Enerflex radiant barrier was listed first under the Structural, Insulation and House-wrap category. The 101 Best New Products article is featured in the November 2010 issue of Professional Remodeler magazine.

About Enerflex Radiant Barrier Insulation
ENERGY STAR approved Enerflex radiant foil barrier insulation is a highly reflective, double-sided, multilayer material that blocks up to 96 percent of the sun's radiant heat. It installs between rafters to the underside of a roof and on vertical surfaces (gable ends) in an attic to reduce solar heat gain into the home. Enerflex is available in 16 and 24 inches on center in precut panels and does not require tools to install. Enerflex is available in rolls and panels and is backed by a 15-year limited warranty. Enerflex also qualifies for the 2010 Energy Tax Credit for a 30% savings or up to $1,500.

For more information and videos, visit the Enerflex newsroom.

Simply put… YES, radiant barriers work. Now don’t worry, I’m not just going to stop there, you will get a detailed explanation.

The reason a radiant barrier works at reducing energy costs is because they lessen the strain on a structure's heating and cooling system. Regardless of whether or not you are heating a structure, or cooling it, radiant foil barrier will stop the transmission of radiant heat (95-97% of it anyway).

Radiant heat is the most efficient form of heat transfer there is. It’s more efficient than convection and conduction put together. The best radiant barrier foil, stops at least 95-97% of radiant heat transmission.

What this means is that in the summer, when the sun is beating down on your roof and radiant heat is raising the temperature in your attic and interior spaces, a properly installed radiant barrier will drastically reduce that radiant heat gain. Vice versa, in the winter, when you are trying hard to keep your home warm, while the heat is rising and leaving your home through the ceiling, properly installed reflective radiant barrier insulation will reduce that heat loss by reflecting radiant heat back into the home.

Some individuals say that reflective radiant barriers are not effective and point to a specific government website (www.ornl.gov/sci/roofs+walls/radiant/rb_tables.htm) as their proof. However, after thoroughly analyzing that data, it only shows that radiant barriers are not effective in certain circumstances: when massive amounts of insulation (R38) are used and where there is no heating or cooling duct-work located in the attic. I will agree, that if you don't have any heating or cooling duct-work in the attic and your ceiling / attic space is very well insulated, then a radiant barrier will do very little towards reducing your energy bills.

Being from the construction industry however, I must say that many homes, especially in the southern regions, do have duct-work and air handlers located in their attic spaces, so even if they have the proper amount of insulation, a radiant barrier would still be quite beneficial.

Despite the fact that radiant barrier insulation has been around for more than a quarter of a century, and it has been proven effective by hundreds of research trials and on-site testing, there are still misconceptions about how radiant barriers work. Consumers have even questioned whether or not reflecting the heat out through the roof can negatively affect the roof shingles.

First of all, radiant barriers are part of a “system,” a cooling/heating strategy. The basic product is a type of aluminum foil or metalized film – much enhanced from your typical kitchen foil. This material is stapled to the underside of the top chord of the roof trusses or to the underside of the roof decking so that there will be an airspace below it to the attic floor. The radiant barrier blocks the radiant heat transfer between a surface that is giving off heat, such as a hot roof, and a surface that can absorb this heat, like conventional attic insulation.

Without a radiant barrier to block the heat coming into the attic through the roof, the heat gets radiated to the insulation which transfers it to the material it touches, primarily your home’s ceiling. Now you've got a hotter house, making you uncomfortable and causing the air conditioner to run longer to get rid of the heat.

Research has found that a radiant barrier system can block up to 97% of the heat that gets radiated downward by the roof before it gets to the insulation.

Even if your attic is well-ventilated, temperatures in a typical attic on a hot summer day can easily reach or exceed 150 degrees F. That’s why you need to get this heat out of the attic before it gets into your living space. Watch a video on simulated attic heat test with and without radiant barrier.

As for its effects on roofing material, it is pretty unlikely that radiant barrier systems can cause any damage to roof shingles even on the hottest days. Roofing materials are obviously made to withstand very high temperatures, and research has found that a radiant barrier only increases their peak temperatures by five degrees or less – not very significant when you consider that peak temperatures on the shingles can easily reach 160 to 190 degrees without causing any damage.

“Too good to be true” may be a misguided perception among many consumers. But every home is different, and insulation and airflow play a significant role in how effective a radiant foil barrier performs. Proper installation of a radiant barrier is also critical to its effectiveness.

As long as your attic is maintained with the right amount of insulation for the area and proper airflow, radiant barriers work. An Energy Star certified radiant barrier will reflect the sun’s radiant heat to help lower attic temperatures in hot climates by up to 30 degrees, allowing you to reduce the amount of energy used to cool your home. Imagine living in a home without a radiant barrier—watch this simulated attic heat test video. Now imagine yourself relaxing in a home with a radiant barrier that helps maintain a constant, comfortable temperature.

Stay cool. Start believing. I do.

Both DIYer and professional installers will find installation of Enerflex Radiant Barrier products to be simple and easy—no special tools required.

As people learn how radiant barrier insulation blocks the sun’s heat to create a more comfortable and energy-efficient home, use of radiant barrier products will become more popular. With radiant barriers becoming more common in environmentally-friendly construction, additional advancements and variations will become available. Most radiant barrier products are nominally sound but they don’t match the ease of installation found with Enerflex Radiant Barrier.

No special tools required.
Unlike most radiant barrier foil, Enerflex doesn’t require prep work at all. Enerflex's metallic foil panels allow you to simply flex the panel into place between your roof joists and release. Once complete, you're ready to start saving on energy costs and high utility bills.

Watch the Enerflex Radiant Barrier installation video
See just how easy it is to install Enerflex radiant barrier panels and start lowering your attic temperatures and your cooling costs.