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Frequently Asked Questions

What is the difference between a Radiant Barrier and Low-E Insulation?
Low-E Insulation means what?
Anybody use reflective insulation?
Does reflective insulation work?
What is non-toxic Housewrap?
What is meant by 'staple insulation to ceiling trusses'?
How to insulate a post frame building?
Where can Reflective Insulation be placed in a roof?
How Do You Insulate for Radiant Heat Between Trusses?
Are You Looking for Product Pricing?
Can You use Low-E Therma Sheet under Shingles?
Does Low-E Insulation in the Attic Damage Shingles?
What are the R-values for the different Low-E products?
Do you use a fan with Radiant Barrier?
Where can you buy Low-E Reflective Insulation?
How can I insulate a concrete slab after it has been installed?
What Low-E insulation can be used for metal buildings?
How effective is Low-E Insulation compared to Fiberglass?
What is the best way to install Low-E Insulation?
How to insulate and put flooring on a concrete pad?
Can insulated vinyl siding be installed over Low-E Housewrap?
Does a radiant barrier work with a ridge vent system?
Do radiant barriers really work on older homes?
How much does a radiant barriers help with heating?



What is the difference between a Radiant Barrier and Low-E Insulation?
Radiant barrier products and Low-E Insulation are sometimes lumped together in the same category. However, they are very different. The difference is in the way they are constructed.

Radiant barrier products are made simply from foil. Usually many layers of foil, merely millimeters thick, have no core and no inherent R-Value. They act only as a barrier against radiant energy, reflecting most of it back inside or outside of your home.

Like radiant barrier products, Low-E Insulation reflects 97% of radiant energy. However, Low-E Insulation with its foam core, the center of the construction, provides a very important function. The foam core is a thermal break, providing the biggest difference between the two products. With the thermal break and a surrounding airspace, Low-E Insulation can provide high R-Values in some applications. There are some Low-E products that work and function without an airspace, all do to its construction. In addition to the thermal break, Low-E Insulation, when installed properly, will also create a vapor barrier. The combination, thermal break and vapor barrier, will help your fight against moisture and condensation. A radiant barrier product can not do this.

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Low-E Insulation means what?
It means the same as Low-E glass. With Low-E glass it is the gas that is between the panes that gives Emissivity. As for the insulation it is the aluminum that gives Emissivity. Emissivity is the ability of a surface to reradiate or give off radiant heat to a cooler surface. All building products have an E rating, most of them over .80. Low-E products have an E rating of .03.

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Anybody use reflective insulation?
I have sold Low-E Insulation to homeowners - HouseWrap, Low-E, Low-E Tab and SlabShield.
I have also sold these products to homeowners plus contractors - Class-A White Trimmed and EZ-Seal.

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Does reflective insulation work?
Yes they do! I placed SlabShield under my daughter's new carpet as the pad. It was over a concrete slab. It stopped the warmth from going through the carpet and into the slab. Remember heat always travels to cold. I have HouseWrap and Therma Sheet on my house. Both of them keep the heat out during the summer and the heat in during the winter.

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What is non-toxic Housewrap?
The insulation HouseWrap is non-toxic because the aluminum is attached to the foam core by a heat process. No toxic chemicals are used. So, if the product is in a fire there will be no toxic smoke around. Not only is this true for HouseWrap but the complete product is manufactured the same way.

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What is meant by 'staple insulation to ceiling trusses'?
This is the way Low-E Tab Material is installed. This product can be used in the attic or under a floor that has a cold area below or a wall that makes the outer side of a house. The product is pushed in the space between the truss or joist. The two tabs, one on each side, should be pushed in until it is even with the outside edge of the truss or joist. You now staple through the tab into the truss or joist.

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How to insulate a post frame building?
You can start by insulating the slab. Before you pour the slab apply Slab Shield. This will keep the slab from reaching ground temperature. Next you can apply Micro-E or Low-E to the side walls before the siding is applied. If you want to use mass insulation on the inside use those without a vapor barrier. The same insulations can be used on the roof before adding the sheathing. Do this by draping the insulation as it is applied over the trusses before finishing the roof...applying the sheathing and metal or shingle products.

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Where can Reflective Insulation be placed in a roof?
The roof can have a radiant barrier installed outside, under the shingles or inside along the upper trusses/rafters. The product to use under the shingles is Therma Sheet. It is manufactured with a drip edge to allow any water to run off. This product is also perfect for under metal, concrete or clay tile roofing.

Inside the roof, with trusses you would use Low-E Tab Material. You would install this product between trusses and staple to the edge of the trusses.

Insulating a roof

With rafters, you can use Micro-E or Low-E. You install these products perpendicular to the rafters stapling to hold in place, but return to nail in place. Use nails with plastic washers.

Insulating a roof

Insulating a roof

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How Do You Insulate for Radiant Heat Between Trusses?
You use a product called Low-E Tab Material. When you apply the product between the trusses it looks like this… [. You slide the product in to the cavity until the tabs become even with the bottom edge of the truss. Do not push the product all the way to the sheathing. At that time you staple thru the tab into the side of the truss. You can also insulate between studs the same way.

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Are You Looking for Product Pricing?
The only way to get pricing online is to Request a Quote. Fill out the Quote form for the product(s)you are interested in and submit the form.

When you do this you will see the retail cost for the product(s) you requested. From there we will determine the shipping cost. Then we will reply with the material cost plus the shipping cost. You can then determine if the total cost is within the project budget.

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Can You use Low-E Therma Sheet under Shingles?
Yes you can.

When people think of a roofing underlayment they most likely will picture asphalt felt paper. ESP Inc. has revolutionized the roofing industry by introducing the first underlayment that will actually work for the homeowner. Therma Sheet Insulation acts as not only an underlayment that will not absorb moisture but also as an insulator. Weighing only 18 lbs the 500 sq.ft. rolls are very easy to install. Installed correctly it will seal around fasteners, provide a complete vapor barrier, and stop radiant heat gain/loss. It can also be left exposed when "drying out" time is needed. No other underlayment can offer this much for the price. Homeowners will be placing a product on their roof that will pay for itself by saving money on utility bills. While most underlayments will deteriorate over time Therma Sheet Insulation will last the life of your roofing system

Read what the RIMA International, Reflective Insulation Manufactures Association International, has to say about the effect of attic radiant barriers on the temperatures of roofing materials. Click to read the Technical Bulletin 103.

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Does Low-E Insulation in the Attic Damage Shingles?
If your attic has both soffit and ridge vents, the answer is NO.

These vents allow air to enter at the soffit and travel up removing the warm air through the ridge. The insulation that can be used is Low-E Tab Material, Micro-E Insulation or Low-E Insulation

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What are the R-values for the different Low-E products?
All specification data, R-value, can be found our Product Line page.

Select the specific product you are interested in. Once you are on the Product page, follow the link at the bottom of the page with the product name plus Product Information.

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Do you use a fan with Radiant Barrier?
If you can, add a ridge vent. The ridge vent will naturally become your fan.

Radiant Barrier on a roof

As you can see in the picture above the air will flow in from the soffit vents and up between the roof decking and the Low-E insulation. All of the hot air stopped by the Low-E insulation will be remove out the ridge vent. Follow the picture for proper installation of the Low-E insulation

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Where can you buy Low-E Reflective Insulation?
You have a few options… The first and quickest is to call K 'n A Distributors at (717) 292-5448, ask for Al and proceed. He will want to know what your project is and how much square footage you want to insulate. If the product you want to use is not appropriate he will let you know which is best. He will let you know what the material cost will be. He will need to determine availability and get back to you. Your order can be placed at that time.

If you want, Al can call you. Go to this link, fill in all of the required information plus data about your project, the product you have selected and the square footage. When Al gets your request he will review it, determine the product and cost. He will then call you with this information. Your order can be placed at that time.

Your last option is to request a quote using this link, fill in all of the required data plus the number of rolls needed for the product you want to use. You can request a quote for multiple products. Al will reply by email with the product cost. This option might require multiple mails to make sure the right product is selected.

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How can I insulate a concrete slab after it has been installed?
You have two options. The first you can do, if the area is a living space, is to apply Therm-E as a carpet pad. Visit this link. Here you will see this application being done. I believe this is the least expensive option of the two.

The other option is to apply another layer, 1" to 1 1/2", of concrete over a layer of Slab Shield on the original slab. The expense to do this may make putting down inexpensive carpet a better option.

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Does reflective insulation work without ridge vent?
Yes, reflective insulation in the attic will work without a ridge vent. However, I do not recommend it. Without some sort of vent all of the heat will collect inside the attic. Eventually that trapped heat will work its way into the house. If you do not have or cannot install a ridge vent, then using turbine vents or power vents will work.

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What Low-E insulation can be used for metal buildings?
If you want to insulate the roof or the sides under metal, you can use any product that has staple flange edges or E-Z seal edges. These products will give you the option of either double sided aluminum (Low-E with a staple flange edge or Low-E with an EZ Seal edge) or bright aluminum on one side and white aluminum on the other side (Econo-E Class-A White or Econo-E Class-A White EZ Seal).

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How effective is Low-E Insulation compared to Fiberglass?
6" of mass insulation slows down only 85 % of conductive and convective heat loss. A second layer of R-19 only slows down an additional 12% of the heat flow passed by the first layer.

PA Energy Book: "NOTE; If you already have two or three inches of insulation (around R-11) in the attic, adding more insulation is not as cost effective as it would be to add insulation to an attic that has none. Insulation obeys the law of diminishing returns - the more you add, the less heat loss each additional inch or unit of R-value prevents."

Your net return on your investment can be less than 7% payback, in some cases that translates in time to up to 25 years.

Energy Design Update Feb 93 "A sober look at attic R-values in hot climates. Increasing the attic insulation from R-19 to R-30 in Atlanta, Georgia, in a 1500 square foot house would save only about $5.00 per year in cooling costs (at $.08 per kwh). The results show that high R-values simply don't have significant impact on total cooling energy costs in hot climates."

C. M. Pelanne, Senior Research Specialist for Johns Manville, Stated "Radiation is the primary mode of all heat transfer. The other two modes, conduction and convection, come into play only as they interfere with the primary mode."

Your net return on your investment - up to 20%!! Average payback time is 7 years or less.

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What is the best way to install Low-E Insulation?
As you start to apply the insulation to a metal building use tape to hold it in place. After the area is fitted go back and add the permanent hardware. Use screws with flat washers or self-drilling screws with neoprene washers.

If you are insulating an area that is framed in wood start out fitting the insulation using staples. A 1/2" staple works every 12". When finished applying the insulation this way it is time to go back and apply the finishing hardware. Use nails with neoprene washers.

Remember, the final step is to always tape the seams. Use a good quality HVAC tape. Why? This is the part that makes it a Radiant Barrier.

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How to insulate and put flooring on a concrete pad?
Use a reflective insulation that is cemented to the concrete. This keeps it from moving when you are walking on the product. The material I suggest when wood or tile is being used is Micro-E, 1/8" 4' x 125' DS TRIMMED. Using this product this way will form a Vapor Barrier and Radiant (Thermal) Barrier. Before applying the flooring make sure you tape all of the seams plus around the wall.

If you will be carpeting the concrete pad I recommend using THERM-E Carpet Pad, 3/8" 4' x 63' FOAM/FOIL/FOAM Trimmed. Using this product will create a Vapor Barrier and Radiant (Thermal) Barrier. It also becomes the carpet pad. Something else… this product will not absorb any spilled item. Again, to complete the task you need to tape all the seams and around the wall before rolling out the carpet.

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Can insulated vinyl siding be installed over Low-E Housewrap?
The short answer is YES. In doing so, you will lose some of the R-value of the House Wrap. With a normal airspace, using non-insulated vinyl siding, the House Wrap will give you an extra 4 R-value. Using insulated vinyl siding over the House Wrap the R-Value for the House Wrap drops to a 1.

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Does a radiant barrier work with a ridge vent system?
Yes is the answer. It is the only approach to using Low-E insulation along the roof line in an attic. If you follow the diagram the way the diagram shows, you will have a great system in place.

No matter how you apply the Low-E insulation, between the trusses with Low-E Tab.

or perpendicular to the rafters with Low-E Micro or Low-E do not disturb the normal air flow. As the products stop the radiant heat it will be removed out the ridge vent.

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Do radiant barriers really work on older homes?
Keep reading and you will get the answer. First, I sell insulation, reflective insulation which is more than a radiant barrier. Second, these products will work on any house, no matter its age.

On an older house, depending on the project, it may require you do other additional DIY projects. Let me know your project and I will let you know if additional work is necessary.

Most likely a home built current to 10-15 years ago will not require additional work. Let me know what your intensions are. I will ask questions about your house just to be sure.

You will see an improvement no matter the age. It could happen that you will get more of an energy savings in an older home. In a newer home you will see an enhancement to the current energy envelope.

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How much does a radiant barriers help with heating?
I do not know how a radiant barrier will help with heating. What I can tell you is the products I sell will help with heating. I sell insulation, reflective insulation, which is more than a radiant barrier. These products have an R value plus an E value. They are also Radiant Barriers and Vapor Barriers.

The R value comes from the product itself and by the way it is installed. The E value comes from the aluminum used in the products. It is the E value that makes these products Radiant Barriers.

As a Radiant Barrier, these products stops heat from traveling to cold. So, just because these products may not have high R values they make up for it by being a Radiant Barrier. This barrier keeps the heat on the inside, during the winter, from escaping to theoutside and reflects the heat on the outside back to itself during the summer.

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