What is the major benefit of adding BTUFOIL™ insulation to a metal building?
BTUFOIL™ Insulation provides increased comfort, energy savings, condensation control, light reflectivity, and noise reduction.

What is the R-Value of your BTUFOIL™?
R-Value indicates resistance to heat loss, and measures a mass insulation’s ability to slow down the transfer of heat. R-Values indicate how well a product absorbs and retains heat energy, not how well it redirects it.

BTUFOIL™ works by reflecting heat energy back in the direction of its source, and BTUFOIL™ ’s true performance is not measured by the R-Value. Just as the absorbency of a raincoat is unrelated to its ability to repel water, the R-Value of BTUFOIL™ is not fully indicative of it’s ability to insulate and redirect heat energy.

The ASTM C236-1224 tests that determine a product’s R-Value yield the following results for BTUFOIL™ Reflective Insulation:
Down = R-15.2
Up = R-6.8
Horizontal = R-8.5

NOTE: All materials have three separate R-Values, as above, depending on the direction of heat flow. Many insulation manufacturers do not provide all three values when labeling their products.

I did not know that there were three modes of heat transfer. Why is this important?

Heat transfer inside and through a building envelope occurs by conduction, convection and radiation. This is important for two reasons. Firstly, each type of heat transfer occurs in different proportions. Radiation accounts for a whopping 75% of all heat transfer through a building envelope. Secondly, different types of insulation protect against different modes of heat better than others. To stop radiant heat, high quality reflective insulation like our BTUFOIL ^tm Reflective Insulation does a far superior job than mass or foam insulation.

What is radiant heat and why does it matter?

Radiant heat is energy. It has no temperature as it travels through your living spaces however when this energy strikes an object, it is absorbed and increases the temperature of that object. The object than emits this energy out the other side causing heat loss or heat gain through the building envelope. A whopping 75% of the heat transfer in your building envelope is in radiant heat energy. Reducing heat gain and heat loss due to radiant heat can dramatically increase your comfort and reduce your energy cost.

What is RADIANT heat?
Simply put, this is heat energy that is radiating through an airspace. If a surface is hotter than an adjacent airspace, it will cast off its energy in the form of infrared waves. These waves are not part of the visible spectrum and as such, are invisible to the naked eye. Consider that temperatures in a dark attic can rise to 150° F. This is due to the roof absorbing the Sun’s radiant heat energy – and in turn, radiating this heat into the dark attic space below.

Now let us consider what occurs in a metal building. Throughout the day, the roof absorbs the Sun’s radiant energy. Energy cannot be created or destroyed, however it can be converted and transferred in different forms. The energy that is built up as heat within the roof, is converted to radiant form and is projected into the interior of the building. This energy manifests itself as heat when it strikes objects inside the building, including people.

Mass insulation products do little to hinder the flow of radiant energy. These materials absorb this energy and retain the heat until it is cast off into the building. As the Sun continues to provide energy, the interior of the building continues to receive it – in the form of heat.

Radiant energy can, however, be controlled. Certain materials - including metalized aluminum - have the ability to redirect these invisible rays. This is why aluminum is used to insulate airplanes, the space shuttle, and even the spacesuits worn by astronauts. Without reflective materials, an astronaut would perish in space. NASA even credits reflective insulation for allowing man and equipment to withstand the harsh environment of space orbit, where temperatures reach over 400° in the sun, and less than -200° in the dark. When installed in metal buildings, BTUFOIL™ effectively redirects the energy that radiates from the underside of the metal. A substantial portion of this energy is reflected upward, away from the building’s interior.

The chart below shows direction and percentages.

        %’S OF HEAT FLOW ARE UP TO THE AMOUNTS INDICATED ON CHART BELOW IN ALL DIRECTIONS OF HEAT FLOW.

                       Summer & Winter                         Winter                                       Summer

Conduction 5% - 7 %

Convection    Up to 45 %

Radiation  Up to 93 %

See the full report here.

How well does BTUFOIL™ work compared to fiberglass?
BTUFOIL™ will stop 96-97% of radiant heat energy (heat is radiated via infrared waves across an airspace). Radiant heat is often overlooked and misunderstood, as R-Values do not take it into account. Radiant heat transfer is responsible for up to 75% of total building heat gain or loss. Traditional Insulation products such as fiberglass, cellulose, and EPS foam board are effective in reducing CONVECTION and CONDUCTIVE heat transfer, but do little to prevent RADIANT heat transfer. Radiant heat energy can either be absorbed or reflected. BTUFOIL™ is faced with a highly reflective - metalized aluminum surface that effectively redirects this energy component.

How does the cost compare to 3” fiberglass?
Typically, the price for BTUFOIL™ products are very close to those of 3” fiberglass, depending on the supplier of the two products.

Does BTUFOIL™ keep a substance cool as well?
BTUFOIL™ does not necessarily ‘cool’ a substance. Rather, it prevents it from taking on heat. For example, an ice-cooler that is lined with reflective insulation can keep it’s contents cool, by reflecting the Sun’s radiant heat away from the interior of the cooler.

Consider the following simple experiment: Ice was placed in 3 separate boxes and it’s rate of melting was recorded. In the boxes insulated with fiberglass and foam, the bags of ice took 24 hours to melt. The bag of ice placed in the box lined with reflective aluminum took 4 days to melt!  This test clearly exposes the fallacy of the R-Value test: A higher r-value does not necessarily mean a better insulator.

Will BTUFOIL™ prevent condensation?
If so, how? Yes. BTUFOIL™ is an outstanding solution to condensation problems. The thermal break provided by the air space prevents warm, moist air inside a building from interacting with cold air on the same surface. When installed correctly - with secure seams - condensation will not occur on the surface of BTUFOIL™.

How does condensation effect reflective insulation?

BTUFOIL™  is among the few insulations not affected by humidity. It's insulating value remains unchanged whether in a dry or very humid climate. In contrast, the r-value of mass insulation diminishes more than 35%, from an R-21 to R-13.65, with only 1.5% moisture content in the air. The average moisture content in homes typically exceeds 1.5%.

Additional studies show that a typical R-19 labeled fiberglass batt actually  has an R Value of R-17.4 before it is installed, and if it is perfectly installed in a wall, it's R Value is R-17.0. In a typical wall installation (not perfect) the R Value is reduced by as much as 28%, thereby delivering an installed R Value of only R-13.7.   Download report here.

How can BTUFOIL™ insulate if it’s so thin?
It’s a common misconception that insulation must be thick to perform. This is because R-Values are closely related to a product’s thickness. For two similar products with different thicknesses, the thinner of the two will always have a lower R-Value than the other.

It is also a common mistake to only consider a material’s R-Value when choosing insulation. It’s highly possible for a thinner reflective material to provide better thermal performance than a thicker non-reflective product, even though the thicker product will have a higher R-Value.

Except for gold and silver, pure aluminum is the most reflective material on earth. The thin aluminum layer reflects radiant heat energy, and this ability is unrelated to the product’s overall thickness.

I am building a warehouse that will not be heated or air-conditioned. Do I need to put any insulation in the building?
To avoid heat gain in the summer as well as condensation problems inside the building, it is necessary to insulate a metal building. The fact that the warehouse is not air-conditioned is even more reason to install BTUFOIL™.

BTUFOIL™ does a great job keeping heat out in the summer, but doesn’t seem as effective keeping the building warm in winter, especially in unheated buildings. Why is this?
Generally, summer heat gain in metal buildings is primarily the result of radiant energy entering the building. Since BTUFOIL™ reflects this energy, it is extremely effective at reducing summer heat gain.

When it is cold outside, the dynamics change. Unlike the summer months, there is not an intense source of radiant energy inside the building for BTUFOIL™ to reflect. Also, the concrete slab is wicking much of the heat energy from the building during the winter. Radiant energy accounts for about one-half of the heat loss during cold seasons.

One other factor affects the thermal properties of a metal building in cold weather. Typically, the sun’s energy actually provides a heat source during the winter. The sun makes the metal surface warmer than the ambient air, and that heat energy is transferred into the building. Installing BTUFOIL™ prevents this. Although winter heat gain is thermally inefficient, it sometimes makes reflective insulation seem less effective, when it is actually doing exactly what it’s supposed to do…stop heat transfer. The bottom line? It can’t be expected of an insulation product to stop heat gain in the summer, and allow it in the winter.

So, how does BTUFOIL™ work in heated buildings in winter?
In heated buildings, the heat generated internally by the furnace, lights, equipment and people is radiated upwards and outwards toward the roof and walls. BTUFOIL™ installed in the roof and walls does the exact same thing in winter that is does in summer. Once the heat energy generated internally strikes it's surface, it reflects 96% - 97% of this heat energy back inside the building, thereby keeping the heat inside the building.  Bottom line here -- BTUFOIL™ always reflects the heat back to it's source, BTUFOIL™ keeps the heat inside during winter and outside in summer.

Keeping cool and / or warm is simply a matter of “ HEAT CONTAINMENT “. That is, Keeping the HEAT OUTSIDE in the summer and Keeping the HEAT INSIDE in the winter. (Keeping = Containing)

Doesn't it make good sense that if the heat cannot come inside in the summer, your A/C will not have to work as hard and as long to keep you cool and comfortable, and doesn't it also make sense that if the heat doesn't escape outside in the winter, your heater / furnace will not have to work as long and as hard to keep you warm and cozy in the winter ? Of course it does, and this also means much lower heating and cooling cost all year long.

Will the reflective surface make my metal hotter than usual?
The heat energy that the metal receives comes directly from the sun. No new energy is being created. Only existing energy, which has already been absorbed by the metal, is reflected back toward the source.

How is BTUFOIL™ installed?
Depending upon the application, BTUFOIL™ can be installed in numerous ways. In pre-engineered steel buildings, BTUFOIL™ is installed either above or below the purlins supporting the metal roof and sidewalls. In new construction, it’s most often installed on the outside of the purlins.BTUFOIL™ usually runs perpendicular to the purlins, and in the same direction as the exterior metal.

In retrofit applications, BTUFOIL™ is installed directly to the under side of the purlins, and running perpendicular to the purlins. BTUFOIL™ requires an airspace, ideally at least ¾”, to effectively redirect heat transfer. This is easily accomplished when installing over purlins spaced 5’ apart, since the products own weight creates a natural drape of 2½” along this span. In retrofit applications, the air space is provided due to the purlin depth, usually 6" - 8".

Can I lay the metal down directly on the BTUFOIL™?
Yes. Theoretically, if it were possible to achieve 100% surface contact with BTUFOIL™ and the metal exterior, the performance of BTUFOIL™ would be compromised.

However, two factors prevent this from ever occurring in metal building installations. First, the natural weight of BTUFOIL™ makes it easy to achieve the necessary ‘draping’ to ensure optimum performance. When pulled tightly during installation, BTUFOIL™ will naturally drape 2½” when spanning purlins spaced 5’ on center. Second, the ribbed profile of exterior metal adds to the airspace already in place.

Finally, BTUFOIL™ provides a thermal break where the exterior metal attaches to the purlins. The only conductive transfer that occurs is via the screws that attach the exterior metal to the purlins.

Do I need to tape the seams?
Taping the seams is highly recommended, especially if interior condensation is an issue. Heated metal buildings in colder climates are especially susceptible to condensation problems, as well as agricultural buildings housing livestock. If there are no concerns about interior condensation, taping the seams is an option. As a rule, we always recommends taping the seams.

What is the best way to tape the seams?
Generally, it is always easier to tape seams from above, just before attaching the exterior metal to the purlins. The most common method for taping seams with 5’ purlin spacing is to install double-tabbed BTUFOIL™ before attaching the metal. Both tabs are brought upward together, and often stapled every 1-2 feet. Foil tape is then applied atop the tabs.

It is also common for the seams to be taped from the inside during the installation. Once the metal panel is in place, it provides a solid backing and allows the tape to be firmly pressed / rubbed down to insure adhesion.
 
How much tape will I need?
First, determine how many linear feet of BTUFOIL™ is being installed. This is approximately how much tape you will need. However, remember to allow at least 20% for tape overlap, scrap, etc… Rolls of BTUFOIL™ Tape are available in  2.5" & 3” widths, and lengths of 150’. A good "ballpark" estimate for tape is one roll of tape for each 500 sq. ft.

What kind of tape works best with BTUFOIL™ ?
We offer several types of BTUFOIL™ Insulation Tapes:
• Aluminum FOIL tape to seal the seams of FOIL faced side.
• Double-sided tape to attach the first course of BTUFOIL™ to the roof edge.

Can I spray wash the material?
Yes, you can keep the surface clean by spray washing the insulation. However, power washing is not recommended.

How is the BTUFOIL™ installed with standing seams?
As with traditional metal roofing,  BTUFOIL™ is installed directly onto the purlins. Installation procedures do not change when used with standing seams.

How is the BTUFOIL™ secured to the purlins?
BTUFOIL™ is taped to the roof edge with double-sided tape, to ease installation. From that point, the material is simply draped over the purlins, and secured under the exterior metal.

Will theBTUFOIL™ compress and secure itself around screw holes?
Yes, the BTUFOIL™ will stay uniform and “seal” around the screw holes ensuring a tight fit. A simple test is to puncture a sample of BTUFOIL™ with a nail, then cup the material and fill with water. Water will not leak around the nail or screw.

Can the bubbles go flat after BTUFOIL™ is installed in a building?
If the bubbles in BTUFOIL™ contain air when the product’s installed, it will maintain this air indefinitely. BTUFOIL™ is produced with high-quality, linear-low density polyethylene, which is an excellent air barrier. Becasue the air pressure inside the bubbles is exactly the same as the air pressure outside, there are no inherent forces in place that will promote deflation.

What if the bubbles lose their air?
It is highly unlikely that any of the bubbles will lose their air given the equal air pressure both inside and out, and due to the quality of polyethylene used. However, it is possible for bubbles to be punctured by sharp objects. However, each bubble is independent of the others, so if one is punctured, the others will still maintain air.

One square foot of BTUFOIL™ contains nearly 600 independent bubbles. The amount of BTUFOIL™ required to insulate a 5000 sq ft metal building will contain nearly 5 million individual bubbles, all of which are independent of each other. If a few of these bubbles do somehow lose their air, there are plenty of adjacent bubbles working together to maintain the performance and thermal break of the material.

Can water get inside the bubbles of BTUFOIL™?
No. Each bubble is independent of the others, and polyethylene is a natural moisture and vapor barrier.

How easily will the product tear?
BTUFOIL™ is produced with linear-low density polyethylene, with very high tensile strength and puncture resistance. When handled properly, it is very difficult to tear the material.

Will BTUFOIL™ degrade or break down?
BTUFOIL™ is made from polyethylene and metalized aluminum. Both of these materials are environmentally stable, meaning they do not biodegrade quickly.

How do animal fluids (urine) affect BTUFOIL™?
Both sides, of BTUFOIL™ are unaffected by animal fluids. Both materials are non-porous, and chemically stable. There is no interaction or degradation that occurs when contact is made with animal urine and fluids.

What is the fire rating of BTUFOIL™?
Most BTUFOIL™ products are classified as Class 1/ Class A in accordance with the ASTM E84 surface burning test. BTUFOIL™ 286 contains a fire-retardant that allows it to also pass the NFPA 286 full room burn test – this product is ideal for exposed insulation applications.

Is BTUFOIL™ a fire hazard?
No. BTUFOIL™ is more prone to melting during a fire, rather than contributing to it. BTUFOIL™ is produced with metalized aluminum and polyethylene – neither of which is a fire hazard.

Will BTUFOIL™ corrode or change color?
BTUFOIL™ is produced with a metalized aluminum. This surface is highly resistant to discoloration or corrosion. Lesser products often contain ‘fillers’ - often, it is these fillers that are discoloring, not the aluminum content itself. For this reason, BTUFOIL™ is always produced with the highest-quality metalized aluminum available. BTUFOIL™ is also coated with a clear resin to further protect the integrity of the surface.

What if it rains on the BTUFOIL™ before it’s installed?
Deionized water (rainwater) has no affect on BTUFOIL™.

Will the BTUFOIL™ tear at the screw holes?
No. The many layers of polyethylene add to the strength of the product and will resist tearing.

Will dust affect BTUFOIL™  performance?
Layers of dust do have an effect on the material’s ability to reflect radiant energy. The degree of reduction in reflectivity has been debated extensively. Conclusions range from 7% to 18% reductions in reflectivity over 10 to 25 years.

Is ¼” rolled foam/foil a better insulator than BTUFOIL™ ?
(Low-E, MicroFoil) These are similar to BTUFOIL™ , only in that they are reflective insulation products. The difference is the strength and effectiveness of the thermal break. Any foam product is prone to de-lamination, due to its porous surface. This material is also subject to blistering, an unsightly by-product of de-lamination. Foam products also lack tensile and puncture strength, and often must include reinforcing scrim to be handled without tearing.

Is ¼” fiberglass with a FOIL facing a better insulator than BTUFOIL™ ?
Like with foam products, fiberglass lacks tensile and puncture strength, and therefore must be laminated to a scrim to be handled without tearing. Fiberglass is also prone to hold heat and moisture, unlike the bubble in BTUFOIL™.  ¼” fiberglass also compresses more than bubble, especially on the purlins. The air vacuum in BTUFOIL™  bubble is a much more effective thermal and condensation break than thin fiberglass, which is why ¼” fiberglass is seldom used in cold climates.

Why is reinforcing scrim added to foam/FOIL and ¼” fiberglass/FOIL insulation products?
The material used in these products, (1/4” foam, ¼” fiberglass) have very little tensile and puncture resistance. For this reason, reinforcing scrim is necessary to prevent tearing when handled, shipped, and installed.

More info on how and why our BTUFOIL ^tm Reflective Insulation and
BTUBUSTERS ^tm  PREMIUM RADIANT BARRIER works so well