AtticFoil is a pure RADIANT BARRIER ONLY. All these other types of products take a sheet of aluminum foil (a radiant barrier) and attach it to a thin layer of insulation usually about ¼” thick.  This insulation is typically fiberglass, foam or plastic bubble wrap material.  The CLAIM is that when you COMBINE a radiant barrier with an insulating product (listed above) that has R-Value, the product MUST be better.

They come up with fancy names like “Attic Energy Barrier” or “Heat Shield” or “Attic Armor” and spend a lot of money on advertising, slick brochures and big sales commissions when in reality all these products are basically the same thing.  A piece of aluminum foil attached to a thin sheet of fiberglass insulation, bubble wrap or foam.

Typically eshield™ and other similar products sell for 5-30 times the cost of AtticFoil.

Are they really better and are they worth it?

First, let me say all these products are NOT BAD products.  They are all GOOD products that are often being used for the WRONG purpose. These products work great in metal buildings and some commercial applications but have now found their way into residential attics.

In a residential attic application, they DO work. Why? Virtually ALL of the heat entering from a roof into an attic is RADIANT HEAT. So, here is the secret:  It’s the FOIL (radiant barrier) doing all the work. The fiberglass, foam or bubbles are just along for the ride and offer virtually no additional benefit in reducing heat flow into a home.  This is why AtticFoil is the ONLY product needed for attic applications and for a fraction of the cost compared to other products.

I believe in giving good information and getting the best “Bang For The Buck” solutions to help consumers make their homes more comfortable and energy efficient.

Here is the bottom line. You DON’T NEED R-VALUE (insulation) ON YOUR RAFERS IN A VENTILATED RESIDENTIAL ATTIC. You need R-Value on your attic floor and you need a radiant barrier either stapled to the bottom of your rafters or laid out over the attic insulation.

Let’s take a look at the ACTUAL R-Value of these other products mentioned above.  Most are about a ¼” thick or less.  Standard foam board by Dow Chemical or Owens Corning has a known R-value of about 3.5 per inch.  An R-13 batt of fiberglass insulation is 3.5” thick. So, common sense tells you that the ACTUAL R-value of eShield and similar products about ¼” thick can be NO MORE THAN AN R-VALUE OF 1.

When you read about claims that these products have R-10 – R-20 values be sure to look at the fine print.  These R-values are ONLY achieved in tightly sealed assembles like a wall and often require over 8” of “Dead” air space.

Since there is typically NO “Dead Air” in a ventilated attic, these products CANNOT achieve a higher R-value than the actual R-value of the ¼” layer of insulation product attached to the foil.

Often, products like eShield are stapled to the bottom of the rafters.  This method works fine to stop the radiant heat, but why waste your money for a small amount of R-value (typically R-1) when you NEED the R-value on the ceiling and not your roofline.  Plus, you can buy By R-19 of blown-in insulation material for about .25/per square ft.

Here is what I recommend.

AtticFoil Radiant Barrier Foil ALONE will accomplish the same benefit as ALL THESE PRODUCTS to stop radiant heat for less cost. Then, spend the money you save on these other products and put in additional attic insulation, if needed. You can easily install R-19 or about 6” or more of additional attic insulation and the total cost will be the SAME OR LESS and you will end up with a BETTER OVERALL REDUCTION IN HEAT GAIN/LOSS.

Remember, traditional attic insulation has R-value. This works to slow conductive heat.  Radiant barriers reflect Radiant Heat.  BOTH types of heat are trying to enter your home on a hot, summer day. The sun heats up the roof and then heat is transferred by radiant heat until it hits the attic insulation.  Then, heat switches form to conductive heat to move through the attic insulation and into your home.  This is why you need BOTH Types. Traditional attic insulation and radiant barrier work together and each do their part.

Radiant barrier is your first line of defense and attic insulation is the second line of defense against heat gain.

Keep things simple, spend your money wisely and be hesitant when you hear outrageous claims for energy savings products. Follow this advise, and you are on your way to making your home more comfortable and energy efficient.

I've written several other posts on this that you might be interested in. Check these posts below:

If you recall there was much excitement when the energy tax credits were extended or revised for 2009-2010.  The 10% tax credit was raised to 30% and the maximum of all tax credits for the period between 2009-2010 was raised from $500 to $1500.

Then, in the Spring of 2009 it was determined that the definition of insulation was expanded to reference the 2009 International Energy Conservation Code (IECC).  Since radiant barrier is not specifically mentioned in the building code, it has been unclear whether or not they qualify.

In December 2009, there was a meeting between the representatives of the reflective insulation industry and the IRS.  In this meeting, representatives presented the case for how radiant barriers should be included to be eligible for the tax credit.

Based on this information, the IRS will allow the tax credit to be taken for products put into service between January 1st, 2009 and December 31st, 2010

It should be noted now that the IRS has NOT made a final ruling on this subject and that this information is NOT binding until a final ruling is made.

The manufacturer’s claim for the tax credit is valid until (and if) the IRS denies the claim.  If the claim is denied, it will NOT be retroactive meaning that you will not be able to claim the tax credit for purchases after the date of the ruling.

Here is my opinion on this.  The IRS probably never intended for radiant barriers NOT to be included.  It’s just how the law was written that because radiant barriers are not specifically mentioned, the fell into a grey area.  Radiant barriers DO help control heat loss/gain and this is really the criteria used to determine if a product contributes to “Energy Efficiency”.  The whole purpose of giving a tax credit is to give incentives to taxpayers to make their homes more energy efficient. Radiant barriers can be an excellent product to move towards these improvements.

For now, I’m comfortable to issue a Manufacturer’s Certification Certificate based on this new information. Please subscribe to this blog for updated information as it becomes available.

I've written several other posts on this that you might be interested in. Check these posts below:

In an attic application, you should ALWAYS use a perforated product. Period.

Perforated Radiant Barrier Foil

Why? Solid products like bubble foil insulation are called “Vapor Barriers”.  A vapor barrier basically stops moisture from moving from point A to point B.  Or, another way to view this is that a vapor barrier will “TRAP” moisture.  I’m not going to get into the technical definition of what defines a vapor barrier (perm rating, etc), but here is an illustration of what IS and IS NOT a vapor barrier.

If you take a wet block of wood and put it inside a bag or an envelope made of perforated radiant barrier attic foil the wood block would eventually dry out.  Therefore, perforated radiant barrier is NOT a vapor barrier.  Moisture ALWAYS goes from wet to dry.  If you did the same test with the wood block inside a plastic bag the wood would still be wet months from now.  If moisture in its vapor form cannot pass through or object won’t “dry” then the product IS a vapor barrier.

Why is this important?

Virtually all (over 70%) of home issues are due to mold, mildew, rot, decay, etc. And moisture is the common theme here.  DRY products don’t grow mold, rot or decay. The bottom line is that moisture in wall and ceiling assemblies is not a good thing.  You want DRY walls and ceilings.

In cooler weather, the moisture INSIDE the home is greater than OUTSIDE.  Think cold and dry.  This is why our lips get chapped in the Winter and not in the Summer.  Since moisture will naturally move from wet (inside) to dry (outside) it will pass through sheetrock, insulation and then into a typical attic.  The LAST thing we want to do is TRAP moisture here.  Moisture, attic insulation and wood do not go well together.  A perforated radiant barrier will allow moisture to pass on through into the attic.  We want our attics to be cool and DRY.

Using a perforated radiant barrier will not change the effectiveness of the reflectivity.  Attic Foil has tiny pinholes about every ½ inch that allow for water in its vapor form to pass through (see picture).  These holes make up a TINY percentage of the surface area and will not change the effectiveness of the radiant barrier.

Solid products like bubble foil insulation are usually not perforated and are a recipe for disaster when installed inside an attic.  Solid (non-perforated) bubble foil is a great product when used correctly in applications like metal buildings.  The problem is that solid bubble foil products are often MISUSED in residential attics. This is especially true if the bubble type reflective foil products are laid directly over the attic insulation.  Moisture will pass through the sheetrock and will get trapped in the insulation below the bubble foil insulation.  This moisture will accumulate until it either condensates (turns to water) or freezes (turns to ice).

This is why it is critical to use a perforated tarp-like radiant barrier product. It will give you all the benefits of reflective insulation without the potential for moisture to get trapped.

I've written several other posts on this that you might be interested in. Check these posts below:

Basically it works this way.  Radiant heat is heat that is transferred across either an air space or a vacuum.  This is how the heat from the sun reaches the earth.  Radiant heat acts similar to a sound wave.  By definition, you MUST have either an air space or a void for radiant heat to even exist.

If you don’t have an air space then you basically have a solid.  Heat can essentially only move through a solid by conduction. This is by direct contact.  This is how an egg cooks on a hot skillet.

So, without an air space, you cannot have radiant heat. Without radiant heat there is no way to have a “Radiant Barrier”.  In fact, because of the conductive nature of pure aluminum, if you install radiant barrier foil WITHOUT the required air space it will actually work AGAINST you and INCREASE Heat flow.

The bottom line is you MUST have an air space on one side of a radiant barrier for it to work.

Click here to view the embedded video.

Looking for more videos on this topic? Check out my posts below.

Paint applied as a Radiant Barrier

You may have recently heard some Radio/TV ads talking about an “Amazing Radiant Barrier Paint that is applied to the underside of your roof”. And how it “reflects” over 75% of the heat to keep your attic cooler and save you money on your utility bills.

Let’s get some facts straight. There is NO such thing as RADIANT BARRIER PAINT.

The term “Radiant Barrier” is supposed to describe products that “Reflect” over 90% of radiant energy (think light colored and/or shiny surfaces like aluminum, silver and gold) or have an emissivity of less than .10. This means they can only “Release” less than 10% of energy as radiant heat (think a potato wrapped with foil to keep heat from being released).

The term “Radiant Barrier” has been hijacked by the paint installers to try to confuse consumers into thinking they are the same. This is like hamburger calling itself a prime steak.

Paints like Sherwin Williams E-Barrier, STS Coatings HeatBloc or Solec LO/MIT are NOT the same as radiant barrier foil.  I’m surprised the FTC has not stopped this fraudulent advertising or a lawyer has not created a class-action suit on the behalf of customers who thought they were being sold a “radiant barrier” by installers.

Paint products technically have their own name.  They are called Interior Radiation Control Coatings or IRCC’s for short. This is not as cool as being called a “Radiant Barrier”. Ironically, most paints don’t even qualify to be an IRCC since the definition of an IRCC is a product that reflects at least 75% or emits less than 25% of radiant heat.  Here are some test results of radiant barrier paints.

Paints will NEVER perform as well as foil radiant barrier products. Foil always reflects 97% of radiant heat energy.  This is an indisputable fact.  Radiant Barrier Foil is always superior to IRCC’s. Paints run into other challenges.  Because radiant barrier paints are “applied” rather than “installed” you get inherent variables in the application process.

First, how can you tell without testing if the product was put on too thick or too thin?  What about painting unprimed wood with paint?  Common sense says it will be absorbed by the wood and reduce the “smoothness” required for a good low emissivity surface. You will also need to paint the deck AND the rafters to get the maximum benefit.

Finally, what about cheating?  These radiant barrier paints are really EXPENSIVE, like $50 per gallon.  I’ve seen guys use cheap silver paint, or mix water with the good paint to extend coverage and reduce costs, which will also reduce the effectiveness of radiant barrier paints.  I’m sure there are many honest installers, but watch out for the bad apples.

The reality is that most radiant barrier paint products end up reducing radiant heat into the attic by about 20-40%.  This is far below the claimed rates of 75%.

There are claims that foil is not effective unless you get the whole roof. This is NOT true.  Any product, whether it be foil or paint has a cumulative effect, the more coverage the better.  A tree over part of your home still helps, right?

If you compare the math, you could actually put foil (reflecting 97%) over half the home and get more heat reduction than applying paint (reflects 20%-40% in real installations) over the whole home.

Don’t believe anyone that says that radiant barrier paint is as good or as effective as radiant barrier foil.  And remember, there is technically NO such thing as radiant barrier paint.

I’m about to reveal the FOUR SILVER BULLETS for making your home more energy efficient in HOT CLIMATES. I’m especially talking about your typical one-story, ranch style home in the South.

Picture yourself sitting in your living room on hot August afternoon. The sun is beating down and it’s about 95º outside. What’s between you and the bazillion degree sun?
Four layers: 1) Roof 2) Attic 3) Leaking Ductwork in the Attic 4) Insulation
If you fix each “layer” between you and the heat from the sun, your home WILL BE MORE EFFICIENT AND COMFORTABLE EVERY TIME!!! Guaranteed. It is not complicated; just follow the recipe for success.

Radiant Barrier Installation

Layer #1 – Roof
Problem: It gets to be about 150º or more and basically acts like a big sponge to absorb heat. This heat is then radiated to the next layer.

Silver Bullet #1 = Radiant Barrier
Installing a radiant barrier is the next best thing to a giant tree instantly landing over your home. Your roof will still absorb the heat, but now rather than that heat being transferred to the home, it will be reflected AWAY.

Layer #2 – Attic

Blocked soffit vent blocks attic ventilation

Problem: Because most attics don’t have enough (or proper) ventilation, the AIR inside the attic basically gets “Clogged” like a drain in a bathtub. The air has nowhere to go and it just heats up and “fills up” the attic. Hot air in the attic will heat up the insulation AND heat up your ductwork that is supposed to have nice cold air running through it.

Silver Bullet #2 = Attic Ventilation
Attic ventilation is real simple. All you need is holes in the top and holes in the bottom. The more holes, the more outside (relatively cool) air moves through the attic and the cooler the attic air. The lowest the air inside the attic can go is near ambient (outside) temperature. The overlooked key to fixing attic ventilation is usually more soffit vents.

Leaking ducts in the attic

Layer #3 – Leaking Ductwork In The Attic
Problem: Putting Ductwork in the attic is about a dumb as making ice cream in the oven. Since you can’t move the ductwork, at least keep it from leaking. Most homes have duct leakage ranging from 15-50%. Older homes and homes with old metal ductwork usually have the highest leakage. What this means is that probably 25% or more of the cold air you are buying is being blown into the attic OR Hot dirty attic air is being SUCKED into your home if the leaks are on the return side of the AC system.

Silver Bullet #3 = Seal Ducts In Attic
If 30% of your water from your sprinkler were spraying into the street, you would fix it today. Why not do the same for your ductwork? Have your ductwork sealed or replaced. A tight duct system will save energy and increase comfort. Plus, indoor air quality will improve by reducing humidity and dust from being pulled into the home.

Attic Insulation being blown in

Layer #4 – Attic Insulation
Problem: Most homes do not have enough attic insulation to create a good thermal barrier between either the heat in the summer and the cold in the winter.

Silver Bullet #4 = Attic Insulation
Increase your attic insulation to the recommend level for your area. Check the DOE (Department Of Energy) for recommendations.

There you go. Four silver bullets for fixing your summer electric bill. Your attic is waiting.

I've written several other posts on this that you might be interested in. Check these posts below:

Click here to view the embedded video.

Looking for more videos on this topic? Check out my posts below.

So, what is the deal with dust?

Watch this video I made to get the quick summary.  Basically, if you use a double-sided radiant barrier, dust will NEVER have an effect on the performance of the radiant barrier IF you leave an air space just below the foil. This is achieved by loosely laying the foil over the attic insulation.

If you staple it up to the bottom of the roof rafters, then there will automatically be an air space below the foil (your attic) if you lay the radiant barrier foil OVER the top of the insulation, there will STILL be a small air space between the foil and the insulation UNLESS you mash it into the attic insulation.

Remember radiant barrier works off TWO Qualities. 1) Reflectivity – This is the ability to reflect the radiant heat.  2) Emissivity – This is the ability NOT to convert stored energy INTO radiant heat.

Even if the top layer of foil gets completely covered with dust, and the bottom layer faces an air space, the radiant barrier will CONTINUE to work off the emissivity quality.

Click here to view the embedded video.

Dust Happens.  But installed correctly, all the dust in the world will not have a significant impact on the effectiveness of double-sided radiant barrier foil.

Looking for more videos on this topic? Check out my posts below.

People always ask. “Should I Add More Attic Insulation or Install A Radiant Barrier”?  I hear this often and the answer is usually BOTH.

Regular attic insulation slows conductive heat.  Radiant barrier reflects radiant heat.  Your home gets a lot of both. Think of your home as a big refrigerator.  How much heat that flows in or out of this big box is determined by basically three things:  1) Inside surface temperature, 2) outside surface temperature and 3) R-Value and thickness of what is between the inner and outer surface.

The walls and top of the refrigerator (or your home) are typically insulated with “regular” insulation. Regular fiberglass or cellulose insulation slows conductive heat. Radiant Barrier acts like shade to reflect radiant heat and make the regular insulation more effective.  A perfect home would be built like a well-insulated refrigerator and be wrapped with radiant barrier foil insulation.  Common sense says that a refrigerator in the shade will use less energy than one in the direct sun.  This is because exterior surface temperatures can easily exceed 150º in direct sun.

If you decrease the outside surface temperature and reduce the difference between the inside/outside temperature, this has a similar effect on reducing heat flow as adding MORE “regular” attic insulation.

Too much of a good thing.

Getting attic insulation up to the recommend level for your area is always a good idea.  However, at some point you reach the law of diminishing returns.  Why?  Regular insulation slows heat, but it also HOLDS heat.  At the end of a hot-sunny day, the insulation in your attic can become a big, thick 130º blanket over the top of your home.  When the sun goes down, this “hot blanket” effect continues to hold and drive heat into the home. Once the roof cools down, the insulation can easily be the hottest part of your whole house. This can make your air conditioner run later into the night.  If you have marginal attic insulation, installing a radiant barrier will make what insulation you already have even more effective.

By combining good attic insulation and radiant barrier, you will get the best of both properties.  Reduction of conductive heat flow AND reduction of radiant heat flow by decreasing surface temperatures of the attic insulation.  Lower surface temperature is like putting the house in the shade.

So, for most homes I recommend doing both.  For maximum benefit, top off your existing insulation AND add a radiant barrier.  They will work together for maximum comfort and energy savings.

I've written several other posts on this that you might be interested in. Check these posts below:

Here is a video I made to illustrate how without an air space you can never have radiant heat.

Click here to view the embedded video.

Looking for more videos on this topic? Check out my posts below.