U.S. patent application number 13/909358 was filed with the patent office on 2013-12-05 for composite face panels for structural insulated panels.
The applicant listed for this patent is KAZAK COMPOSITES, INCORPORATED. Invention is credited to Woodrow W. Holley.
Application Number | 20130318908 13/909358 |
Document ID | / |
Family ID | 49668565 |
Filed Date | 2013-12-05 |
United States Patent
Application |
20130318908 |
Kind Code |
A1 |
Holley; Woodrow W. |
December 5, 2013 |
COMPOSITE FACE PANELS FOR STRUCTURAL INSULATED PANELS
Abstract
Composite face panels for use with structural insulated panels
(SIP) are provided to form a suitable replacement for structural
insulated panels that employ oriented strand board or plywood. The
structural insulated panel has a sandwich structure with a
generally planar, insulating core. A composite face panel is
disposed on each of the opposed surfaces of the insulating core.
The insulating core composition includes an insulating material
that is formed of an expanded polystyrene or a rigid polyurethane
foam. Each composite face panel includes a core and face sheets on
each surface of the core. The core composition includes mixture of
a resin binder and a fire retardant. The resin binder can be formed
of a methacrylate modified urethane, and the fire retardant can be
formed of alumina trihydrate.
Inventors: |
Holley; Woodrow W.; (Malden,
MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KAZAK COMPOSITES, INCORPORATED |
Woburn |
MA |
US |
|
|
Family ID: |
49668565 |
Appl. No.: |
13/909358 |
Filed: |
June 4, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61655176 |
Jun 4, 2012 |
|
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|
Current U.S.
Class: |
52/741.4 ;
156/264; 428/220; 428/304.4; 428/313.9; 428/339; 428/423.1;
428/423.3 |
Current CPC
Class: |
E04C 2/246 20130101;
E04C 2/296 20130101; Y10T 428/269 20150115; Y10T 428/31554
20150401; E04B 1/94 20130101; E04C 2/243 20130101; E04C 2/284
20130101; Y10T 156/1075 20150115; Y10T 428/31551 20150401; Y10T
428/249953 20150401; Y10T 428/249974 20150401 |
Class at
Publication: |
52/741.4 ;
428/423.1; 428/339; 428/220; 428/304.4; 428/313.9; 428/423.3;
156/264 |
International
Class: |
E04B 1/94 20060101
E04B001/94; E04C 2/284 20060101 E04C002/284 |
Goverment Interests
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] This invention was made under Department of Energy Grant No.
DE-SC0003731. The Federal Government may have certain rights in the
invention.
Claims
1. A structural insulated panel comprising: a sandwich structure
comprising an insulating core having a generally planar
configuration and two opposed surfaces, a face panel disposed on
each of the two opposed surfaces; the insulating core comprising an
insulating material; and each face panel comprising: a core
comprising a mixture of at least a binder resin and a fire
retardant, the amount of binder resin being at least 25 percent by
weight of the mixture, the amount of fire retardant ranging from 50
to 200 parts per hundred relative to the binder resin; and face
sheets on opposed surfaces of the core of the face panel, each face
sheet comprised of a fiber reinforcing material embedded in the
binder resin, the binder resin comprised of the same binder resin
as in the core of each face panel.
2. The structural insulated panel of claim 1, wherein the binder
resin is comprised of a methacrylate modified urethane, the amount
of binder resin being at least 25 percent by weight of the mixture,
the fire retardant is comprised of alumina trihydrate, and the
amount of alumina trihydrate ranging from 50 to 200 parts per
hundred relative to the binder resin.
3. The structural insulated panel of claim 1, wherein the fiber
reinforcing material is comprised of a glass fiber material.
4. The structural insulated panel of claim 1, wherein each face
panel has a thickness ranging from 1/4 inch to 3/4 inch.
5. The structural insulated panel of claim 1, wherein each sandwich
structure has a width of at least 4 feet, a length of at least 8
feet, and a thickness of at least 3 inches.
6. The structural insulated panel of claim 1, wherein the
insulating material is comprised of an expanded polystyrene or a
rigid polyurethane foam.
7. The structural insulated panel of claim 1, wherein the
insulating material is comprised of a phenolic foam, an expandable
polyethylene foam, or a polyisocyanurate.
8. The structural insulated panel of claim 1, wherein the core of
each face panel further includes a phase change material.
9. The structural insulated panel of claim 1, wherein the core of
each face panel further includes microballoons.
10. The structural insulated panel of claim 1, wherein the core of
each face panel further includes a pigment.
11. A method of manufacturing the structural insulated panel of
claim 1, comprising: pultruding an arrangement of the core mixture
of the binder resin in an uncured state and the fire retardant with
the face sheets on the opposed surfaces through a pultrusion die
for a time and at a rate sufficient to cure the binder resin;
cutting the cured product exiting the pultrusion die into sections
transverse to a pultrusion direction, each section comprising one
of the face panels; and laminating one of the face panels on one of
the two opposed surface of the insulating core to form the sandwich
structure of the structural insulated panel.
12. A method of constructing a structure comprising: providing a
plurality of structural insulated panels according to claim 1; and
incorporating the structural insulated panels into the
structure.
13. A composite face panel comprising: a face panel comprising: a
core comprising a mixture of at least a binder resin and a fire
retardant, the binder resin comprised of a methacrylate modified
urethane, the fire retardant comprised of alumina trihydrate, the
amount of binder resin being at least 25 percent by weight of the
mixture; and the amount of alumina trihydrate ranging from 50 to
200 parts per hundred relative to the binder resin, and face sheets
on opposed surfaces of the core of the face panel, each face sheet
comprised of a glass fiber reinforcing material embedded in the
binder resin, the binder resin comprised of a methacrylate modified
urethane.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit under 35 U.S.C.
.sctn.119(e) of U.S. Provisional Patent Application No. 61/655,176,
filed on Jun. 4, 2012, the disclosure of which is incorporated by
reference herein.
BACKGROUND OF THE INVENTION
[0003] Structural insulated panel (SIP) construction is a labor
saving method of construction that employs minimal wood framing and
provides a durable continuous insulation. SIPs have a web and
flange design that functions like a structural I-beam, offering
increased structural integrity. The SIP has a sandwich structure
with a core of an insulating material, which functions as the web,
between two face sheets, which function as the flanges. The face
sheets are typically formed of oriented strand board, a wood
material. An SIP can be used for walls and roofs of buildings. The
inherent air-tightness is greater than wood-frame construction,
which leads to greater energy efficiency. The SIP can be
pre-fabricated in large panel sizes, leading to construction
efficiencies.
SUMMARY OF THE INVENTION
[0004] The present invention relates to composite face panels for
use as face sheets of structural insulated panels (SIP) to form a
suitable replacement for structural insulated panels that employ
oriented strand board or plywood. The composite face panel is a
sandwich structure with a core material and two opposed face
sheets. The core is formed of material composition including at
least a binder resin and a fire retardant. In one embodiment, the
core is formed of a material composition including a methacrylate
modified urethane (MAMU) as the binder resin and alumina trihydrate
(ATH) as the fire retardant. The composite face panels in turn form
the face sheets of an SIP having a core formed from an insulating
material. One or more other additives, such as phase change
materials, light-weight structural fillers, and pigments, can be
included in the core of the face panels.
[0005] A method of manufacturing the structural insulated panel
(SIP) is also provided, including pultruding the face panels and
laminating the face panels to an insulating core material to form a
sandwich structure. Also, a method of constructing a building is
provided, including incorporating the structural insulated panels
into the building.
[0006] Additionally, a composite face panel is provided. The
composite face panel comprises a core comprised of a mixture of a
binder resin comprised of methacrylate modified urethane and a fire
retardant comprised of alumina trihydrate and face sheets comprised
of a glass fiber reinforcing material embedded in a methacrylate
modified urethane.
DESCRIPTION OF THE DRAWINGS
[0007] The invention will be more fully understood from the
following detailed description taken in conjunction with the
following drawings:
[0008] FIG. 1 is a schematic cross sectional illustration of a
structural insulated panel including a composite face panel of the
present invention.
[0009] FIG. 2 is a schematic illustration of a pultrusion process
for manufacturing a composite face panel of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0010] The disclosure of U.S. Provisional Patent Application No.
61/655,176, filed on Jun. 4, 2012, is incorporated by reference
herein.
[0011] FIG. 1 illustrates an embodiment of composite face panels 20
incorporated in a structural insulated panel (SIP) 30. The SIP
includes a central core 32 having a generally planar configuration
with two opposed flat surfaces 34. A composite face panel 20 is
disposed on each of the flat surfaces 34 of the core. Each face
panel comprises a sandwich structure with a generally planar core
22 and two opposed face sheets 24 on each of the two opposed flat
surfaces 26 of the face core.
[0012] The core 22 of each face panel 20 is a material composition
having good fire, smoke, and toxicity (FS&T) properties and
that provides a good thermal barrier. The material composition
includes at least a binder resin and a fire retardant. In one
preferred embodiment, the material composition includes a mixture
of a methacrylate modified urethane (MAMU) as the binder resin and
alumina trihydrate (ATH) as the fire retardant that meets desired
FS&T requirements. The face sheets 24 are formed of a fiber
reinforcing material impregnated with the same binder resin. The
binder resin provides the matrix backbone for both the core
composition and the face sheets. The fiber reinforcing material can
be a glass or carbon fiber material. These materials are also
resistant to water, weather, and insect damage, particularly during
the installation period.
[0013] The selection of the binder resin is based on considerations
of physical properties of the final matrix and the process
conditions required to effect the resin cure. Different properties
are achieved in part by the constituents used to construct the
backbone of the individual polymer chains and also by the
functional chemical groups (often located at the ends of the
polymer chains). The chemical functional groups determine how the
material cures or hardens to its final form. This is accomplished
by the functional groups on each polymer chain reacting chemically
with a second chain and/or through an intermediate monomer such as
styrene or methyl methacrylate and continues to propagate until a
complete matrix is formed by the combined effects of the cross
chain reactions (referred to as "cross linking"). In general,
thermosetting plastics are named for the type of chemical
functionality that is used to cure them. Hence phenolic resins have
phenol chemical groups that cause reactions between polymer
molecules under the influence of heat to form the final matrix.
Vinyl esters have vinyl groups that react with other vinyl groups
to form very large polymers using particular catalysts. Both
methods function by cross linking but under different conditions
and with different results with respect to the physical properties
that they produce.
[0014] As noted above, in one embodiment, a suitable resin system
for the face panel is a methacrylate modified urethane (MAMU). It
is a hybrid of a vinyl ester resin (chemical functionality) and a
urethane resin (backbone polymer portion). This combination results
in a binder resin that combines the ease of processing of a vinyl
ester resin with the toughness and good mechanical properties of a
urethane resin. The cost of this hybrid is approximately equal to a
general purpose vinyl ester, which is significantly less than the
cost of typical phenolic resins. Pultrusion die temperatures are
much lower than for phenolic resins. This makes the product much
easier and quicker to process, further reducing overall costs. The
MAMU resin does require addition of a fire retardant additive to
meet fire standards. This is easily accommodated for within this
resin system since it has a high capacity for accepting solid
additives with minimal effects on its cure or mechanical
properties. Also, the cured part has very low water absorption,
less than 0.1% by weight.
[0015] A suitable commercially available MAMU resin binder for the
face panel is Crestapol 1212 from Scott Bader Company. Crestapol
1212 is a urethane methacrylate resin in methyl methacrylate (MMA)
and styrene monomers. Due to specific resin backbone and monomer
developments, this resin is advantageous over established
thermosetting pultrusion resins: its tough resin backbone offers
improvements in mechanical properties of pultruded profiles and its
fast reactivity allows increased rates of productivity (i.e.,
increased pultrusion line speed). Its mechanical properties are
superior to that of phenolic and other resins. Its very low
viscosity (usually less than 100 cps) allows high filler loadings
to be used. When used with alumina trihydrate (ATH), the low smoke
and toxic fume aspects of the base resin allow the stringent fire,
smoke, and toxic fume international standards to be achieved.
Alumina trihydrate (ATH) filled Crestapol 1212 resin passes ASTM
E662, ASTM E162 and ASTM E84 tests. (Annual Book of ASTM Standards,
2009, Vol. 4.07, "Test Method for Specific Optical Density of Smoke
Generated by Solid Materials," p. 717; "Test Method for Surface
Flammability of Materials Using a Radiant Heat Energy Source," p.
643; "Test Method for Surface Burning Characteristics of Building
Materials," p. 567.)
[0016] Also as noted above, in one embodiment, the inorganic
mineral alumina trihydrate (ATH) is added to the MAMU resin binder
as a fire retardant to meet the FS&T requirements. ATH is a
white crystal powder available in several degrees of whiteness,
particle sizes and particle distributions. ATH is a material that
releases water from its molecular structure upon being heated above
a specific temperature limit. The released water is converted to
steam which cools the fire and once converted to steam the water
vapor smothers the fire by depriving it of oxygen. This approach is
particularly effective since the water vapor is available at the
instant that the fire attempts to spread and is available exactly
at the point where it is needed due to its prior incorporation into
the matrix structure. ATH is approximately one-third chemically
combined water [2Al(OH).sub.3.fwdarw.Al.sub.2O.sub.33H.sub.2O]
which begins to be released at 230.degree. C. (446.degree. C.). The
resulting endothermic reaction cools the product below flash point,
reducing the risk of fire, and acts as a vapor barrier to prevent
oxygen from reaching the flame. Thus, this water release results in
active flame retardancy and smoke suppression. In contrast, many
non-phenolic resins incorporate halogen elements (such as chlorine
and bromine) into their structure to achieve fire retardancy. In
general this approach is not acceptable for building applications
due to the toxic by-products (chlorine and bromine gases) that are
released in a fire situation. The use of ATH as an additive with
MAMU resin avoids this problem.
[0017] J M Huber Corporation's MoldX A105 is a suitable
commercially available ATH additive. It is an optimized alumina
trihydrate (ATH) flame retardant capable of high loading levels in
resin binders. Since MoldX A105 is a non-halogen flame retardant it
not only satisfies flame spread requirements, but also satisfies
the toxicity test. Moreover, incorporating ATH filler with MAMU
resin reduces the material cost even further, as the ATH filler
typically is about one-fourth the cost of the binder resin.
[0018] Other suitable binder resins include unsaturated polyester
(UPR), vinyl ester, and epoxies. Other suitable fire retardants
include calcium sulfate dehydrate (gypsum) (CaSO.sub.42H.sub.2O)
and other hydrates of inorganic salts. The amount of binder resin
should be at least 30 percent by weight of the mixture, and the
amount of fire retardant should range from 50 to 200 parts per
hundred relative to the binder resin. In the preferred embodiment
described above, the amount of MAMU in the core material should be
at least a minimum of 25 percent by weight, and the amount of ATH
can range from 50 to 200 parts per hundred relative to the
resin.
[0019] The face sheets 24 of the face panel 20 are comprised of a
fiberglass material embedded within the MAMU resin. The face sheet
materials can include other fiber materials (such as carbon
fibers), although glass fibers are generally the most cost
effective. The longitudinal edges can also be wrapped or covered
with the same fiber material.
[0020] The fiber material can be arranged in any suitable manner.
Any number of plies or layers can be used. For example, in one
embodiment, two or more plies or layers of one-dimensional
fiberglass fabric arranged at alternating 0.degree./90.degree. can
be used. The plies can be stitched together if desired. Woven
fabrics or nonwoven mats can also be used. A glass to resin ratio
ranging from 30 to 60 percent by weight is satisfactory. The fiber
material can be preimpregnated with the resin binder if desired.
The weight of the fiber material can be selected to achieve a
particular mechanical strength and to control thickness. The weave
and density of the fiber material can be selected to provide good
nail bolding capacity during construction.
[0021] One suitable commercially available glass fabric is E Glass
(18 oz/yd.sup.2) supplied by the Northern Fiberglass Company.
Another suitable commercially available glass fabric is E-LTM 2408
(32 oz/yd.sup.2) supplied by Vectorply Corporation.
[0022] The face panels 20 described herein are used as a component
within an SIP construction 30. The SIP includes an insulating core
formed from an insulating composition or material. Suitable
insulating materials include an expanded polystyrene (EPS) and a
rigid polyurethane foam (PUR). Other insulating materials that may
be suitable for certain applications include a phenolic foam, an
expandable polyethylene foam (EPE), and a polyisocyanurate (PIR,
also known as polyiso and ISO). The face panels 20 typically range
from 1/4 to 3/4 inch in thickness, although it can be greater or
less. The core 32 typically ranges in thickness from 2 to 12
inches, although it can be greater or less. The overall thickness
of an SIP panel 30 typically ranges from 3 to 14 inches.
[0023] Other structural components can be included in the SIP
construction. For example, thermally reflective films can be
included. A traditional or legacy interior wall or ceiling finish
(such as dry wall, plaster, or the like) can be provided on one of
the face panels. A traditional or legacy roof treatment (for
example, roofing felt and shingles) or exterior wall treatment (for
example, clapboards) can be placed over one of the face panels of
the SIP. The traditional interior wall or ceiling finish may be
spaced from the SIP construction by an air cavity. Spacers can be
provided to form the air cavities.
[0024] Optionally other additives can be included in the core 22 of
the face panel 20. For example, a phase change material (PCM) can
be incorporated into the material composition of the core. A PCM
assists in shifting the energy load from the peak times to other
times of the day. When a material changes phase to a more random
physical state, such as from solid to liquid, or from liquid to
vapor, an amount of heat energy is absorbed. Conversely, when a
material changes from a vapor to a liquid or a liquid to a solid,
an amount of heat energy is released. The heat change associated
with this change of state is referred to as "latent heat." Heat
absorbed or desorbed as a material experiences a change in
temperature between the state changes is referred to as "sensible
heat." A phase change material (PCM) is a material that is capable
of storing a usefully large amount of energy as latent heat. The
solid-to-liquid or liquid-to-solid phase changes are the most
practical for using such a material as a thermal storage medium.
Materials for interior building applications typically have a
narrow required temperature range. Paraffins and fatty acids and
salt hydrates, when suitably encapsulated, are generally suitable
as PCMs in embodiments of a building panel as described herein. The
PCM is encapsulated in, for example, a thin, high melt temperature
thermoplastic shell of an acrylic. The encapsulated PCM when added
to the material of the core absorbs excess heat without a
temperature rise during high heating periods and eliminates or
delays thermal impact on the building interior. The amount of PCM
in the core material can range from, for example, 30 to 70 percent
by weight.
[0025] A suitable commercially available PCM is Micronal.RTM. DS
5001X from BASF Company. This PCM is a formaldehyde-free
microencapsulated latent heat storage material that is durable and
provides efficient isothermal storage of the peak thermal loads,
which usually occur during the day, in a defined temperature range,
and releases the stored heat with a time delay (for example, in the
evening or at night).
[0026] Other additives can be included in the composition of the
core 22 of the face panel 20. For example, a light-weight filler
can be added, which can serve one or more purposes. Operationally,
a light-weight filler can assist in rendering the binder material a
comparatively "dry," non-tacky composition that is readily
flowable. Thus, handling, mixing and transferring of the core
composition are more operationally friendly. Also, the replacement
of denser components with a light-weight filler reduces the overall
weight of the part. Additionally, a light-weight filler provides
thermal insulation properties and contributes to increasing the
R-value of the system. Since an SIP application has significant
structural requirements, a light-weight filler for the core can be
chosen not only on the basis of its potential for density reduction
and thermal insulation value but also on the basis of its
mechanical strength, especially resistance to compressive crushing
or distortion.
[0027] Glass microballoons are one light-weight additive suitable
to meet the structural and reduced weight requirements of an SIP
application. Microballoons are hollow glass spheres that come in a
range of sizes, densities and crush strengths. The microballoons
encapsulate air, which adds to the insulation properties of the
SIP. The microballoon properties are determined by the overall
average diameter of the microballoons and the average thickness of
the microballoons' glass walls. In general, smaller diameter
microballoons are denser and stronger than larger diameter
microballoons. Likewise, thicker walled microballoons are denser
and stronger than thinner walled microballoons. A variety of
products featuring many combinations of differing wall thicknesses
and diameters are available. A product line of microballoons is
offered by 3M Corporation. A combination of two 3M microballoons,
grades K-1 and S-32, have been found to be suitable. The density of
K-1 microballoons is 0.125 g/cm.sup.3 and their crush strength is
250 psi. The density of S-32 microballoons is 0.32 g/cm.sup.3 and
their crush strength is 2,000 psi. It was found that a ratio of 80
parts of S-32 microballoons and 20 parts of K-1 microballoons
provided the maximum achievable density reduction while maintaining
almost all of the crush strength of the stronger S-32
microballoons. The actual ratio of total microballoon weight to
resin weight, however, can vary from product to product based on
the percentage of other additives, such as PCM, that is used and
the amount of microballoons incorporation that the mixture could
tolerate and remain operationally functional.
[0028] A pigment can be added to the composition of the core 22 of
the face panel 20 if it is desired to give the core material a
color. Many suitable pigments are known.
[0029] The face panels can be manufactured in any suitable manner
capable of producing large sized parts with dimensions of at least
4 ft. by 8 ft. Suitable processes capable of producing these sizes
include pultrusion, extrusion, hand lay-up, and vacuum assisted
resin transfer molding (VARTM) processes.
[0030] In one embodiment, a pultrusion process is used to
manufacture the panels. In this case, the core mixture should have
properties suitable for a pultrusion process. For example, the
viscosity should range from 300 to 5,000 cP. The rate of cure of
the resin should range from 0.5 to 5.0 ft/min. Operating
temperatures for the die curing zone are from 70.degree. F. to
420.degree. F.
[0031] In a pultrusion process, the components for the core 22 are
mixed, and the face sheets and core mixtures are fed into a heated
forming die and pulled through the die by grippers, or
caterpullers, at the exit end. Curing of the thermosetting resin
occurs in the die. FIG. 2 illustrates a schematic example of a
pultrusion process. The die is fabricated to have the thickness
dimensions required of the finished panel product. Upon entering
the die, the fabrics and other materials consolidate to the exact
shape and size of the die cavity. The heated die thermally cures
the resin and converts the loose combination of reinforcing fabrics
plus solid and semi-liquid constituents into a consolidated,
hardened structural panel. Heat flows into the composite matrix to
drive the cure process via direct conduction from the heated die
surfaces to the composite components. The cure of the composite
material is largely a function of the temperature profile to which
it is subjected. The temperature profile includes the mold surface
temperature(s) and the amount of time spent at those
temperature(s). These parameters can be controlled and are highly
correlated. For pultrusion, the temperature is controlled by
control of the mold surfaces and the process line speed. The
material is pulled through the die at a constant speed by means of
reciprocating grippers at a rate that allows for thorough curing
during the material's residence time in the die. Cooling down of
the panel occurs as it moves further down the line. The pultrusion
process enables a continuous high volume to be produced with low
fabrication unit costs. As the material exits the die, it is cut in
the cross direction into segments of any desired length (in the
pultrusion direction). At this stage, the cross directional or cut
edge is exposed core material. If desired, these edges can be
covered, for example, with a reinforced tape material or other
suitable edge treatment, to protect the edges from damage during
handling and installation. In some applications, it is not
necessary to cover the cross directional edge.
[0032] The composite face panels 20 can be attached to insulating
core material 32 in any suitable manner to form a SIP 30. For
example, the face panels 20 can be laminated to the core 32 using
any suitable adhesive. Heat and/or pressure can be applied as
needed.
[0033] The composite panel described herein can replace current
wood and glue-based sheathing products, including OSB and plywood,
as sheathing products in roof or wall elements of a building,
including as components of SIPs. Oriented strand board (OSB)
sheathing is formed of processed wood and wax with a phenol
formaldehyde adhesive. Plywood sheathing, which is used for similar
purposes, has a similar composition to OSB. Neither OSB nor plywood
provides an advantage with respect to thermal storage or insulation
capability. Also, current wood-based products are susceptible to
environmental deterioration during storage and during construction.
Wood based products are also inherently vulnerable to insect
destruction and water absorption damage which may lead to mold
growth and decay.
[0034] The composite panels described herein provide structural
integrity, robustness and durability compared to wood-based
counterparts. The composite panels repel water, provide no
nutrients for microbial or insect sustainability, and are stable
against thermal and UV deterioration. The acquisition costs of the
panels are competitive with current wood-based products, while
offering lower total ownership costs with respect to maintenance,
energy savings, and life cycle. The fabrication and attachment
methods used in wood construction can be used with the present
composite panels. The panels can be installed using current
practices and tooling with no significant changes from existing
practices. The composite panels have demonstrated mechanical
properties superior to wood products and fire, smoke and toxicity
(FS&T) properties comparable to wood products. The panels can
obviate the need for additional components or steps to achieve a
desired level of fire protection, such as the addition of gypsum
board to a wood-based SIP.
[0035] The panels can be installed by typical cutting and nailing
building methods and can be fabricated in traditional sized sheets
or pieces, for example, up to 1 inch thick, 10 feet wide and of
lengths of 50+ feet. The fiberglass fabric selections (for face
sheet construction) based on mechanical properties also provide
sufficient nail holding capability. The two face sheets 26 of the
construction provide the bulk of the resistance to nail pulling.
This resistance is a function of the fabric selections with respect
to weave density and thickness. The primary criteria for the face
sheet fiberglass selections are to provide the maximum mechanical
stiffness and strength at the lowest cost and weight.
[0036] The invention is not to be limited by what has been
particularly shown and described, except as indicated by the
appended claims.
* * * * *