Frequently
Asked Questions
Q.) Why are
[Greenix] SIPs much better?
A.) SIPs save time, money, and energy.
They outperform other building methods in virtually every aspect because
of the structural strength, ease of erection, and insulation value of the
components.
When someone says "R-value", what they
are talking about is resistance to heat flow in a given medium, such as
fiberglass insulation. The higher the number, the greater the resistance
to flow. Thus, a product with a value of R-25 is much better than a
product with a value of R-13.
In reality, this reasoning doesn't take into
account all the other components that go into making a wall: wood or steel
studs every 16 or 24 inches reduce the overall R-value, and allow airflow
within the wall space. In addition, other construction materials and
components, such as bracing, nails or screws, wiring and switch boxes, and
any number of things that are not insulation, and, in all likelihood, have
low R-values, negatively affect the overall quality of an insulated wall,
floor, or ceiling. Poor installation of fiberglass batt insulation can
also reduce the R-effect significantly. A wall with fiberglass insulation
rated at R-13 can have an actual result of R-10 or less due to these other
factors.
Labratory Testing
A new study by the Oak Ridge National Labs (ORNL)
in Tennessee proves that a 4" SIP wall outperforms traditional
2" x 4" stick and batt construction, and even edges out 2"
x 6" construction in terms of thermal performance. SIPs (if made with
structural “skins” such as OSB) are structural elements. There are no
studs or braces to cause breaks in the insulative action. The end result
is a more comfortable, energy-efficient building that performs up to
specifications in real-world conditions. Unlike stick and batt
construction, which can be subjected to poorly installed - even missing -
insulation; the nature of the SIP Supply SIP is such that the structural
and insulative elements are joined and bonded together as one. There are
no hidden gaps. A solid layer of foam insulation is integral to panel
construction.
The ORNL study found that SIPs perform at
approximately 97% of their stated R-value overall, losing only 3% to nail
holes, seams, splines and the like. Wiring chases are preformed into the
foam core, providing a continuous layer of insulation keeping the elements
out and the interior free of drafts and cold spots. SIP Supply SIPs are
superior to traditional, old-fashioned methods of building construction.
Q.) Why do we use
polyurethane rather than polystyrene?
A.) Simply put, we feel that by
delivering Polyurethane (PUR), we are delivering a better SIP product.
Please read why we feel this way at Foam
Core Comparison.
Q.) Why are
Greenix SlPs stronger?
A.) Greenix Panels are a structural composite acting
like an I-beam. The skins act like the flanges and the rigid core is
similar to the web. In short, the three components work together, rather
than against one another. The composite assembly yields stiffness,
strength, and predictable responses to loads. Greenix Panels have an
integral tongue and groove system for joining panels together that also helps
carry the structural load. SIPs resist both compressive forces from above
and buckling and warping forces from the sides. SIP Supply tests to the American
Society of Testing and Materials (ASTM) E72-04 “Standard Test Methods of
Conducting Strength Tests of Panels for Building Construction” for
compression, transverse, and racking loads. Depending on the type of
structural test being administered, SIPs range between two and seven times
stronger than traditional framing.
Not only do test results show the panels are
stronger, but real-life natural disasters have proven it. The great
Hanshin (Kobe, Japan) and North Ridge earthquakes, Hurricane Andrew, a
Colorado tornado, a Portland gas explosion, and an Omaha fire, have done
more to prove SIP strength to homeowners, architects, and builders than
all the scientific tests.
Q.) Are the high efficiency
claims valid?
A.) Yes. Four key factors make the average SIP
building very energy-efficient.
1.) Polyurethane foam provides higher
insulating value per inch than traditional fiberglass or cellulose
insulation.
2.) There is much less wood framing within the typical
panel, which increases total R-value.
3.) The foam is continuous and is
not susceptible to the commonplace flaws found in average batt
installations.
4.) Foam, when bonded directly to the exterior and
interior wall “skins,” doesn't allow air infiltration around it.
SIP-made buildings are vastly more
energy-efficient, stronger, quieter, and draft free than older building
methods likes stud framing with fiberglass batt insulation. Fiberglass is
sometimes used for furnace filters because air moves through so freely.
Polyurethane foam consists of billions of tiny cells with solid
polyurethane cellular walls. Air cannot flow from cell to cell or between
cells. Rigid foam insulation is used as solid component insulation in
almost every industry concerned about heat transfer, such as the
refrigeration industry, for its inherent efficiency and prevention of air
movement. These attributes are built right into the SIP Supply SIPs
panels. Less air movement or leakage translates into far fewer drafts,
fewer penetrations of noise, much lower energy bills, and a significantly
more comfortable and controllable indoor environment. You can have a
quieter, more comfortable home and office.
Q.) Does the insulation lose
R-value over time?
A.) No. Greenix Panels contain a polyurethane foam formulation that
stabilizes at a relatively high R-value (about R-7 per inch of thickness)
once it is placed in a building's wall, floor, or ceiling system. The
R-value of a fully cured polyurethane panel is about two-and-half times
higher than that of a fiberglass-insulated stud wall.
Q.) Are SIP homes too tight for
good indoor health?
A.) No. Research indicates that the best way to
provide a building (such as a home or office) with good indoor air quality
requires two essential steps.
1.) The building has to be built as
tightly as practical; it is easier to control air movements in a tight
home than in a leaky one.
2.) The building must have modern, upgraded
mechanical ventilation features in the HVAC system so that it provides an
appropriate and steady flow of fresh air. These modern HVAC features also
add energy-efficiency.
Q.) How do you wire SIP houses?
A.) Wiring a Greenix Panel building takes a little
extra planning prior to construction. Greenix Panles are designed with a conduit chase and
electrical boxes in the foam according to the structure's plan and
“blueprints.” Then, an electrician simply “fishes” the wire
through the conduits to where the wire is needed. Wiring chases and boxes
can be provided for electrical outlets and switches, wiring junctions,
cable television outlets, telephone outlets, computer circuits, etc.
Q.) What about plumbing?
A.) Plumbing is not usually placed in exterior walls,
but rather through the floor into the bottom of cabinets. Where exterior
wall vent-pipes are necessary, chases can be formed in the foam cores.
Island or loop vents are also common practices and can be found in the
plumbing codes.
Q.) How do you make the
openings for doors and windows?
A.) Doors and windows are identified in the building
plan. As part of the manufacturing process, door and window openings
are framed and blocked out. When foam is injected into the panel, the door
and window frames become an integral part of the panels.
Q.) What about SIPs in fires?
A.) Fire requires three components: ignition, oxygen,
and fuel. SIP Supply SIPs have no "air" within the solid core of
the insulation. The fire cannot "run up the wall" cavity, as is
the case with traditional stud construction. Polyurethane foam does not
melt. SIPs have passed every standard fire test that is required of
wood-based or “Type V” construction. To the surprise of some building
researchers, data from extensive laboratory fire testing as well as
reports from actual house fires indicates that SIP structures tend to be
more resistant to house fires than standard stud structures.
SIP Supply tests their panels to the American Society
for Testing and Materials (ASTM) E84-04 “Standard Test Method for
Surface Burning Characteristics of Building Materials” for smoke spread
and flame spread. The panels have a Class 1 foam core. The foam components
are formulated to have a flame spread of less than 25 units and smoke
spread of less than 400 units.
Q.) Are ants and termites a
problem in panels?
A.) No more than in conventional construction. In
climates where either termites or ants can cause problems, panel
manufacturers recommend that all homeowners use the same preventive
treatments (topical sprays around foundations, termite shields, etc.) that
they would use in a stick-framed home. Note, however, that the foam within
the panels does not provide food value for insects.
Q.) Is an
Greenix Panel a
"green building product?" Is it environmentally safe to make and
use?
A.) Yes. SIP homes require considerably less framing
lumber than a conventionally framed home. This saves trees. OSB is made
from the 37% of a tree that is normally waste from making solid lumber.
Solid lumber, as used in typical wood-frame homes, requires 63% of the
wood from harvested trees. SIP homes, pre-cut in the factory, result in
far less “job-site waste.” The small amount of wood scraps resulting
from the SIP manufacturing process at the manufacturing facility is used for other
products or recycled, rather than going into landfills.
We use a low-pressure foaming system designed
to maximize the advantages of the foam properties. The cured foam is inert
and non-hazardous. The foam process used by SIP Supply uses no “ozone
depleting substances”, such as chlorofluorocarbons (CFCs),
hydrochlorofluorocarbons (HCFCs), hydrobromofluorocarbons (HBFCs), halon,
methyl bromide, carbon tetrachloride, or methyl chloroform. Only
EPA-approved materials are used in the manufacture of Greenix Panels. Greenix
Panels polyurethane foam contains
no formaldehyde. The foam contains agricultural-based oils derived
from soy beans, corn, sugar beets, and/or sugar cane. The foaming
equipment is cleaned with hot water and a detergent, and the small amount
of residue is safely disposable.
Q.) How much are they? Do SIPs
walls cost more than frame walls?
A.) When evaluating the cost of building with a SIP
you need to look at the overall construction costs and long-term operating
costs, not just the cost of the material. SIPs result in less waste, less
field labor requirements (along with the associated field labor overhead
costs, such as transportation, lodging, meals, benefits, etc.), much
faster construction time (and fewer weather delays), lower HVAC equipment
costs, and greater comfort. Long-term operating costs for utilities are
greatly reduced. SIPs are even more competitive when the design is
optimized to incorporate them. Consequently, architects design dimensions
at two-foot and four-foot increments, engineer roof pitches at steeper
angles to increase loft square footage, and make other similar adjustments
to take full advantage of SIP capabilities. SIPs, therefore, usually
result in lower overall building costs and better value.
|
