Kingspan Insulation
Kingspan Group

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Frequently Asked Questions

 

Is GreenGuard “green”?

Do your products have recycled content?

What is extruded polystyrene?

Does your XPS foam rot?

What about mold, mildew, and insects? 

Wood is a good insulator. Why would I want foam on the outside of my building?

What is the difference between regular insulation (batts or blown fill) and foam boards? 

Does your foam have sound resistance properties?

Some GreenGuard siding underlayments have a reflective surface and claim a higher R-Value. How does this work?

Should the reflective surface be placed to the outside or the inside?

Can fanfold siding underlayment be used in place of building wrap?

Why do you need building wrap?

If I use spray foam insulation on the inside of my wall cavity, why do I need building wrap?

Is it OK to install the building wrap upside down, sideways, or with the printing facing the wall?

What kind of building wrap should be used behind fiber cement siding?

If I have a brick wall, why do I have to worry about water?

I understand that foam sheathing insulates better than wood, but foam sheathing
does not have structural properties. How can I use foam sheathing in place of wood
sheathing and maintain structural stability?



Where can I buy GreenGuard products?

GreenGuard products are sold through building material distributors and dealers
in the U.S. and Canada. To find a source near you, please
click here
to submit an inquiry and a representative will contact you.

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Is GreenGuard “green”?

Yes, GreenGuard is green in more than color. GreenGuard products help reduce energy
consumption and improve the durability of the structure. Plus GreenGuard XPS insulation
contains up to 30% post-industrial recycled content. Click
here
to see the full GreenGuard Green Building story.

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What is extruded polystyrene?

GreenGuard insulation is extruded polystyrene (commonly referred to as XPS), a foam
insulation material manufactured by an extrusion process. Plastic resin pellets
are fed into an extruder, blended with a blowing agent, and extruded through a die
into the shape of the insulation board. The result is a board with consistent closed-cell
construction that is rigid, sturdy, does not crumble, does not absorb water, and
has an R-Value of 5.0 per inch of thickness. For more information, click here to view the Extruded Polystyrene Foam Association
website.

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Do your products have recycled content?

Yes. GreenGuard insulation board contains up to 30% post-industrial recycled materials,
while GreenGuard building wraps contain up to 5%.

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Some GreenGuard siding underlayments have a reflective surface and claim a higher
R-Value. How does this work?

Reflective surfaces reflect (do not emit) radiant heat. For example, our 3/8”
thick siding underlayment has an R-Value of 1.5. With a reflective surface, the
effective R-Value of that product can be as high as 3.6, when installed using a
½” uniform, parallel dead air space on the reflective side. This follows
the “ASHRAE Handbook of Fundamentals” basic principles of reflective
insulation properties. With the air space partially achieved, the effective R-Value
is something between the 1.5 of the foam and the maximum 3.6. Be aware that some
manufacturers may make misleading claims of very high R-Values achieved with reflective
surfaces. For information on reflective surface thermal performance, click here to visit the Reflective Insulation Manufacturers
Association website.

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Should the reflective surface be placed to the outside or the inside?

Since reflective surfaces are designed to reflect radiant heat, it is common practice
to install the radiant surface to the predominantly warm side of the wall. In an
extremely cold climate, that would mean installing with the reflective surface inward.
In a hot climate, it would be installed with the radiant surface outward. In climates
that are more balanced, it may be installed either way, depending on whether the
objective is to reduce heat loss in winter or reduce heat gain in summer.

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Does your XPS foam rot?

No, XPS foam does not rot. XPS foam is designed to be used behind walls and below
grade, not as an exterior finish. It will eventually deteriorate with prolonged
exposure to the sun, so it needs to be covered with a cladding.

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What about mold, mildew, and insects?
GreenGuard extruded polystyrene (XPS) foam insulation and building wraps are made
of synthetic materials that are generally recognized as not providing a food source
for insects, fungus, mold, or mildew. GreenGuard building materials should always
be properly installed and stored.

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Wood is a good insulator. Why would I want foam on the outside of my building?

Contrary to common conception, wood is not such a good insulator, at least when
measured against other insulating materials. A 2 x 4 wall stud (3½”
across) covered by 7/16” thick OSB sheathing has a total R-Value of about
4.0. In comparison, XPS sheathing only ½” thick has an R-Value of 3.0,
and 1” thick XPS insulation board has an R-Value of 5.0. By replacing or covering
wood sheathing with XPS insulation, you create a “thermal break.” That
is, you break the transfer path of heat and cold through the wood framing and sheathing.

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Why do you need building wrap?

Building wrap is used in both residential and commercial applications for two primary
functions: (1) as an air barrier or retarder and (2) as a secondary water barrier
to block water that gets through the exterior cladding. Both functions work to improve
the energy efficiency and durability of the structure.

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Is it OK to install the building wrap upside down, sideways, or with the printing
facing the wall?

In the case of RainDrop® building wrap, the product must be installed with the
correct side to the exterior and the drainage channels vertical, or at a slight
angle from vertical, for the product to function properly. (Horizontal drainage
channels do not really work.) Performance of flat wraps is not particularly affected
by install direction, from a fabric perspective. However, installing wrap consistently
indicates that you have followed guidelines to achieve a proper water-resistive
barrier. Care should be taken to install the wrap in a shingling fashion (check
local codes for overlap requirements). In addition, the appearance of the final
job sends a message. You can guess what message a sloppy, inconsistent installation
sends.

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If I have a brick wall, why do I have to worry about water?

Brick, like other exterior claddings, does a good job of deflecting hard rain. However,
water soaks through brick. That is the reason you need air space between brick cladding
and the wall sheathing and “weep holes” at the bottom of a brick wall.
You also need a secondary weather barrier to protect the wall structure from water
that gets behind the brick. The same is true for other claddings: wood, vinyl, fiber
cement, stucco, and stone.

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Can fanfold siding underlayment be used in place of building wrap?

GreenGuard siding underlayments are in compliance with the ICC-ES “Acceptance
Criteria for Foam Plastic Sheathing Panels Used as Weather–resistive Barriers”
(AC71). This means that GreenGuard fanfold siding underlayments may be used in either
new or retrofit construction applications without an additional water-resistive
barrier (felt building paper or building wrap), when they are installed in strict
accordance with the installation instructions. (These instructions are available
in the Product Downloads.)

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Does your foam have sound resistance properties?

GreenGuard XPS foam is not designed as a sound control product. While it does reduce
sound intrusion a small amount, that is not its purpose. To design a wall with true
soundproofing, you should research the products and techniques for that specific
purpose.

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What is the difference between regular insulation (batts or blown fill) and
foam boards? 

Batt and blown fill insulations (fiberglass, cellulose, etc.) are a more economical
way to achieve insulation in wall cavities than foam boards. A common batt insulation
used in the 3½” thickness of the cavity in a 2’ x 4’ wall
structure has an R-Value of either 11 or 13. The same thickness of XPS foam board
would yield an R-Value of 17.5 to 18, but at a higher cost. However, the rigidity
and consistency of the XPS foam board, as well as its resistance to water, make
it an excellent product for the outside of the wall, where even in thicknesses of
½” it adds an insulating R-Value of 3.0.

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What kind of building wrap should be used behind fiber cement siding?
Fiber cement siding, like wood or vinyl siding, is nailed tightly to the wall sheathing.
If water gets through the siding, it has no place to go. The best type of wrap to
use is a drainage wrap such as RainDrop®, with built-in drainage channels to
move water away from the wall.

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If I use spray foam insulation on the inside of my wall cavity, why do I need
building wrap?

Spray foam wall cavity insulation gives excellent R-Value, is consistent, and, if
installed to do so, can be a barrier to air infiltration over parts of the wall.
However, it does nothing to protect the wood sheathing. A building wrap is required
to protect the exterior wall sheathing against water intrusion. In addition, the
building wrap adds another barrier to air infiltration.

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I understand that foam sheathing insulates better than wood, but foam sheathing
does not have structural properties. How can I use foam sheathing in place of wood
sheathing and maintain structural stability?

XPS foam sheathing not only offers better insulation than wood sheathing, but it
also provides water resistance. You can use GreenGuard XPS foam sheathing in place
of wood sheathing by employing alternate bracing methods such as “let-in bracing”
or steel strapping to achieve structural properties. Another alternative is to use
wood sheathing in the corners to achieve structural properties and foam sheathing
in the non-structural portions of the wall. This approach is done following the
“prescriptive method” outlined in the codes. For general guidelines
on your local seismic and wind zones, please download our PLYGOOD Ultra Wall Bracing
Guide (click here to access Product Downloads).
(You must check your local codes for final requirement.) Another simple option is
to sheath the house completely in wood and install a layer of XPS insulation on
the exterior as added insulation.

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