ASTM D7445-18

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D7445 − 18 An American National Standard
Standard Specification for
Rigid Poly(Vinyl Chloride) (PVC) Siding with Foam Plastic
Backing (Backed Vinyl Siding)
This standard is issued under the fixed designation D7445; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
NOTE 3—There is no known ISO equivalent to this standard.
1. Scope*
1.7 This international standard was developed in accor-
1.1 This specification establishes requirements for vinyl
dance with internationally recognized principles on standard-
siding with integral foam plastic backing, where the siding is
ization established in the Decision on Principles for the
manufactured from rigid PVC compound. Performance re-
Development of International Standards, Guides and Recom-
quirements and test methods addressed by this standard include
mendations issued by the World Trade Organization Technical
materials properties and dimensions, warp, shrinkage, impact
Barriers to Trade (TBT) Committee.
strength, expansion, appearance, and wind load resistance.
Methods of indicating compliance with this specification are
2. Referenced Documents
also provided.
2.1 ASTM Standards:
NOTE 1—Backed vinyl siding is composed of two major components:
D618 Practice for Conditioning Plastics for Testing
the siding and the backing. It is intended that the siding portion comply
D635 Test Method for Rate of Burning and/or Extent and
with Specification D3679. Applicable portions of Specification D3679 are
included in this specification. Additional requirements that pertain only to Time of Burning of Plastics in a Horizontal Position
the backing as a separate material, or to the combination of siding and
D696 Test Method for Coefficient of Linear Thermal Expan-
backing as a whole, are also included.
sion of Plastics Between −30°C and 30°C with a Vitreous
1.2 Backed vinyl siding shall be tested with the backing
Silica Dilatometer
material in place or removed, as specified in the applicable
D883 Terminology Relating to Plastics
requirement or test method.
D1042 Test Method for Linear Dimensional Changes of
Plastics Caused by Exposure to Heat and Moisture
1.3 The use of PVC recycled plastic in this product shall be
D1435 Practice for Outdoor Weathering of Plastics
in accordance with the requirements in Section 4.
D1600 Terminology for Abbreviated Terms Relating to Plas-
1.4 Siding produced to this specification shall be installed in
tics
accordance with Practice D4756. Reference shall also be made
D2244 Practice for Calculation of Color Tolerances and
to the manufacturer’s installation instructions for the specific
Color Differences from Instrumentally Measured Color
product to be installed.
Coordinates
NOTE 2—Information with regard to siding maintenance shall be D2457 Test Method for Specular Gloss of Plastic Films and
obtained from the manufacturer.
Solid Plastics
D3679 Specification for Rigid Poly(Vinyl Chloride) (PVC)
1.5 The values stated in inch-pound units are to be regarded
Siding
as standard. The values given in parentheses are mathematical
D3892 Practice for Packaging/Packing of Plastics
conversions to SI units that are provided for information only
D4226 Test Methods for Impact Resistance of Rigid Poly-
and are not considered standard.
(Vinyl Chloride) (PVC) Building Products
1.6 This standard does not purport to address all of the
D4756 Practice for Installation of Rigid Poly(Vinyl Chlo-
safety concerns, if any, associated with its use. It is the
ride) (PVC) Siding and Soffit (Withdrawn 2023)
responsibility of the user of this standard to establish appro-
D5206 Test Method for Windload Resistance of Rigid Plas-
priate safety, health, and environmental practices and deter-
tic Siding
mine the applicability of regulatory limitations prior to use.
1 2
This specification is under the jurisdiction of ASTM Committee D20 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Plastics and is the direct responsibility of Subcommittee D20.24 on Plastic Building contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Products. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved Jan. 1, 2018. Published February 2018. Originally the ASTM website.
approved in 1979. Last previous edition approved in 2017 as D7445 – 17. DOI: The last approved version of this historical standard is referenced on
10.1520/D7445-18. www.astm.org.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7445 − 18
D5947 Test Methods for Physical Dimensions of Solid 3.2.5 wind load design pressure rating—the maximum wind
Plastics Specimens pressure that a backed vinyl siding product is rated to
D7209 Guide for Waste Reduction, Resource Recovery, and withstand, based on testing under Test Method D5206.
Use of Recycled Polymeric Materials and Products (With-
3.2.5.1 standard wind load design pressure rating—the
drawn 2015)
wind load design pressure rating for a siding product when
D7793 Specification for Insulated Vinyl Siding
installed 1) over a sheathing material designed and attached
E84 Test Method for Surface Burning Characteristics of
such that it is capable of resisting 100 % of positive and
Building Materials
negative wind pressures occurring under design conditions at
E631 Terminology of Building Constructions
the building location; and 2) with the standard fastening
E1753 Practice for Use of Qualitative Chemical Spot Test
method specified in building codes, general installation
Kits for Detection of Lead in Dry Paint Films
instructions, and the siding manufacturer’s instructions.
G147 Practice for Conditioning and Handling of Nonmetal-
3.2.5.2 alternative wind load design pressure rating—the
lic Materials for Natural and Artificial Weathering Tests
wind load design pressure rating for a siding product when
2.2 ASCE Standard:
installed over a sheathing not designed and attached such that
ASCE 7-10 Minimum Design loads for Buildings and Other
it is capable of resisting 100 % of positive and negative wind
Structures
pressures occurring under design conditions at the building
2.3 International Code Council:
location, or when the siding is not fastened in the standard way;
International Building Code
as specified by the manufacturer.
International Residential Code
6 3.2.5.3 Discussion—The standard test conditions,
2.4 Vinyl Siding Institute, Inc.:
configuration, and fastening method used in this specification
VSI Vinyl Siding Installation Manual (2015)
are specified in 6.14, while alternative sheathing and installa-
2.5 Structural Building Components Association:
tion conditions are specified by the manufacturer and must be
ANSI/SBCA FS 100-2012 Standard Requirements for Wind
reflected in the product’s installation instructions. Alternative
Pressure Resistance of Foam Plastic Insulating Sheathing
ratings apply only when the specified sheathing and fastening
Used in Exterior Wall Covering Assemblies
conditions are used. See Annex A1 for information on differ-
ences between the standard wind load design pressure rating
3. Terminology
and alternative wind load design pressure ratings, and how to
3.1 Definitions are in accordance with Terminologies D883,
determine standard and alternative design pressure ratings.
E631, and D1600, unless otherwise specified.
3.2.6 temperate northern climate—in weather testing, a
North American metropolitan area testing site located within
3.2 Definitions of Terms Specific to This Standard:
73 to 100°W longitude and 37 to 45°N latitude.
3.2.1 backed vinyl siding—a vinyl cladding product sold
with manufacturer-installed foam plastic backing material as
3.2.7 vinyl siding—a shaped material, made principally
an integral part of the cladding product. The vinyl cladding
from rigid poly(vinyl chloride) (PVC), that is used to clad
portion of backed vinyl siding meets the definition of vinyl
exterior walls of buildings; in this standard, vinyl siding refers
siding. Backed vinyl siding is intended to be installed only with
to the rigid profile to which the backing material is attached.
the integral backing.
3.2.7.1 Discussion—Any exception to a homogeneous rigid
3.2.2 backing material; foam plastic backing—a layer or PVC compound is present in a coextruded or laminated
capstock.
layers of plastic that has been intentionally expanded to
produce a reduced-density plastic containing voids consisting
of open or closed cells distributed throughout the plastic. 4. Materials and Manufacture
3.2.3 nominal—the value that a manufacturer consistently
4.1 The vinyl siding, exclusive of backing material, shall be
uses to represent a specific property or dimension of a vinyl
made of one or more layers of poly(vinyl chloride) (PVC)
siding product in public claims including, but not limited to,
compound. Any layers of materials other than poly (vinyl
product literature, advertisements, quotations, and certificates
chloride) (PVC) compound shall be kept to less than 20 % by
of conformance.
volume. This limitation does not apply to the backing material.
3.2.4 process average thickness—the rolling, arithmetic
4.2 Where rigid PVC recycled plastic as defined in Guide
mean of average specimen thicknesses measured according to
D7209 is used, the siding containing the PVC recycled plastic
6.5 for a specific product during all productions runs for the
shall meet all of the requirements of 3,Terminology; 4, Mate-
most recent six month period.
rials and Manufacture; and 5, Physical Requirements.
4.3 The poly(vinyl chloride) siding material, exclusive of
4 backing material, when tested in accordance with Test Method
Available from American Society of Civil Engineers (ASCE), 1801 Alexander
D635, shall not exceed an average extent of burn of 4 in. (100
Bell Dr., Reston, VA 20191, http://www.asce.org.
Available from International Code Council (ICC), 500 New Jersey Ave., NW,
mm), with an average time of burn not to exceed 10 s. A
6th Floor, Washington, DC 20001, http://www.iccsafe.org.
minimum sample thickness of 0.035 in. (0.9 mm) is required.
National Housing Center, 1201 15th Street NW, Suite 220, Washington, DC
Warning—The flammability testing data, conclusions, and
20005, http://www.vinylsiding.org
6300 Enterprise Lane, Madison, WI 53719, http://www.sbcindustry.com recommendations of Test Method D635 relate solely to the
D7445 − 18
measurement and description of properties for classification of than the permitted variation in Table 1, and each individual
the poly(vinyl chloride) siding material in response to flame reading shall not vary more than 10 points from the average.
under controlled laboratory conditions and shall not be used for Gloss of smooth and embossed vinyl siding shall be tested in
the description or appraisal of the fire hazard of vinyl siding accordance with 6.11.
under actual fire conditions. 5.1.8 Uniformity of Color—The color specified shall be
uniform on the exposed surface of the vinyl siding panels,
4.4 The foam plastic backing shall have a Flame Spread
except on the case of variegated colors. When tested in
Index not greater than 75 and a Smoke Developed Index not
accordance with 6.13, the total color change, ΔE, between a
greater than 450 when tested separately under method E84.
production specimen and the appropriate reference specimen or
4.5 The PVC compound when extruded into siding shall
agreed-upon color coordinates shall not vary by more than 1.5,
maintain uniform color and be free of any visual surface or
and the chromatic coordinates thereof shall not change by more
structural changes, such as peeling, chipping, cracking, flaking,
than 6Δa = 1.0 and 6Δb = 1.0.
H H
or pitting.
5.1.9 Weathering:
4.6 The PVC compound shall be compounded so as to 5.1.9.1 The vinyl siding shall maintain a uniform color and
provide the heat stability and weather exposure stability be free of any visual surface or structural changes such as
peeling, chipping, cracking, flaking, and pitting when tested in
required for the siding market application.
accordance with 6.10.
4.7 Backed vinyl siding shall not contain elemental lead
(Pb) or compounds of that material other than traces incidental NOTE 4—Weathering-conformance-testing requirements are to reflect
performance of a “typical” extrusion siding profile representing a specific
to raw materials or the manufacturing process. This limitation
color of PVC compound and a specific extrusion technology. In no case is
applies to both PVC substrate and to any cap or film material,
there an implied requirement for testing all the various shaped and sized
as well as the backing material. Compliance with this require-
siding profiles produced in this color. The lengthy outdoor weatherability
ment shall be demonstrated by one of the methods in 6.16.
testing for new products may be performed concurrently with market
development and sales of siding to existing markets. Completion of
weatherability testing prior to marketing of the product is not required.
5. Physical Requirements
5.2 Requirements Applicable to Backed Vinyl Siding—The
5.1 Requirements Applicable to Vinyl Siding—The provi-
provisions of 5.2.1 – 5.2.3 apply to backed vinyl siding,
sions of 5.1.1 – 5.1.8 apply only to the vinyl siding, exclusive
including the integral foam backing material. Testing shall be
of any backing material. Where necessary to perform testing,
conducted with the backing material in place, as described in
the backing material shall be removed.
the referenced test method.
5.1.1 Length and Width—The nominal length and width of
5.2.1 Surface Distortion—The backed vinyl siding shall be
the siding shall be as agreed upon between the purchaser and
free of bulges, waves, and ripples when tested to a minimum
the seller. The actual length shall not be less than ⁄4 in. (6.4
temperature of 150°F (66°C) in accordance with the procedure
mm) of the nominal length and the actual width shall be within
in 6.12. This distortion is called “oil-canning.”
6 ⁄16 in. (1.6 mm) of the nominal width when measured in
5.2.2 Wind Load Resistance—The siding shall withstand a
accordance with 6.3 and 6.4.
minimum static test pressure and a standard wind load design
5.1.2 Thickness—These requirements pertain only to mea-
pressure rating shall be determined.
surements of the portions of the siding that are exposed after
5.2.2.1 Minimum Test Pressure—Backed siding shall be
installation of the panel, measured in accordance with the
able to withstand a minimum test pressure of 22.5 lbf/ft (1077
procedure in 6.5. The average thickness of each specimen shall
Pa) when tested in accordance with 6.14. The average maxi-
be no less than 0.035 in. No individual measurement shall be
mum sustained static test pressure determined in 6.14 shall be
thinner than 0.003 in. below the nominal thickness. The
equal to or greater than this value. If the manufacturer of
process average thickness as defined in 3.2.4 shall be no
backed siding provides documentation to support compensa-
thinner than 0.001 in. below the nominal thickness.
tion for pressure equalization, the test pressure shall be
5.1.3 Camber—A full length of siding (typically 10 or 12 ft
determined from Annex A1 using the documented pressure
(3.05 or 3.61 m)) shall not have a camber greater than ⁄8 in.
equalization factor.
(3.2 mm) when measured in accordance with 6.6.
5.1.4 Heat Shrinkage—The average heat shrinkage shall not
NOTE 5—The static test pressure of 22.5 lbf/ft (1077 Pa) for backed
siding was established to withstand structural loading conditions that
exceed 3.0 % when determined by the method described in 6.7.
occur in wind exposures of approximately 110 mph (177 km/h) (V ) for
ASD
5.1.5 Impact Resistance—Siding shall have a minimum
mean roof heights of 30 ft (9.1 m) and less in exposure category B, and
impact strength of 60 in.·lbf (6.78 J) when tested in accordance
corresponds to 30.0 lbf/ft (1436 Pa) negative design pressure, to match
with 6.8.
the default wind design conditions of Table R703.3(1) in the 2015
5.1.6 Coeffıcient of Linear Expansion—The siding shall International Residential Code. Provision is made for compensation for
pressure equalization specific to the product if supporting documentation
have a coefficient of linear expansion not greater than 4.5 by
-5 -5
10 in./in./°F (8.1 by 10 mm/mm/°C) when tested in accor-
TABLE 1 Gloss Values
dance with 6.9.
5.1.7 Gloss—The gloss of smooth and embossed vinyl Manufacturer’s Specified Gloss Value Permitted Difference from
Manufacturer’s Specified Gloss Value
siding shall be uniform across the exposed surface. The
Less than or equal to 35 ±8
average of all readings for a panel determined in 6.11.2.5 shall
Greater than 35 ±10
not differ from the manufacturer’s specified gloss value more
D7445 − 18
-5
is provided, using procedures in Annex A1.
α = coefficient of linear thermal expansion, 4.5 × 10
NOTE 6—Refer to Annex A1 for an explanation as to how the negative
in./in./°F or actual known coefficient for material used,
design pressure was established, and for applications where the effective
as determined by 6.9,
negative design pressure as specified in ASCE 7-10 is different from 30.0
L = length of panel, inches, and
lbf/ft (1436 Pa) (for example, wind-zone areas greater than about 110
T = centering tolerance: 0.25 in.
c
mph (177 km/h) (V ) (225 km/h (V )) or mean roof height above 30
ASD ULT
ft (9.1 m), or exposures other than exposure category B).
(1) The design-pressure values can be negative (suction 6. Test Methods
loads) or positive. The negative values are the largest in
6.1 General—The inspection and test procedures contained
magnitude and are the values used in this specification.
in this section are used to determine the conformance of
NOTE 7—In that the siding is being tested as a weather-resistant exterior
products to the requirements of this specification. Each pro-
product applied to an existing exterior structural wall, forces (negative)
ducer who represents its products as conforming to this
working to pull the siding off the wall, fasteners, or disengage locks will
specification shall be permitted to use statistically based
be the most important criteria for testing. Positive wind forces test the
integrity of the total wall sections, and do not provide a measure of the sampling plans that are appropriate for each manufacturing
performance of the siding.
process, but shall keep the essential records necessary to
document, with a high degree of assurance, his claim that all of
5.2.2.2 Standard Wind Load Design Pressure Rating—The
the requirements of this specification have been met. Addi-
standard wind load design pressure rating shall be determined
tional sampling and testing of the product, as agreed upon
from the results of testing in accordance with 6.14, using the
between the purchaser and the manufacturer, are not precluded
procedures described in A1.3.
by this section.
NOTE 8—The standard design pressure rating is valid for applications
6.2 Conditioning and Test Conditions—Condition the test
where the siding is installed over sheathing and its fastening that are
specimen in accordance with Procedure A of Practice D618 and
capable of independently resisting both positive and negative wind
test under those conditions, unless otherwise specified herein.
pressures occurring under design conditions at the building location. For
applications over other sheathing, a different design pressure rating is
6.3 Length—Lay the specimen on a flat surface and measure
applicable, and is determined in accordance with A1.3. Determination of
with a steel tape. Measure the length of a siding panel to the
a rating other than the standard design pressure rating is not required by
nearest ⁄16 in. (1.6 mm) at the center, the butt edge, and the
this section.
bottom of the top lock. The average of the three measurements
5.2.2.3 Alternative Design Pressure Ratings—Design pres-
is the actual length.
sure ratings other than the standard wind load design pressure
6.4 Width—Interlock two long specimens, each at least 26
rating, for use with different sheathing materials or using
in. (600 mm) long, in the normal mode for installation. Lay the
different installation or fastening, are permitted to be deter-
two specimens on a flat surface. Measure to the nearest ⁄16 in.
mined in accordance with testing under 6.14, using the
(1.6 mm), the distance between the lowest butt edge of the top
procedures in Annex A1.
specimen and the lowest butt edge of the bottom specimen.
5.2.3 Nail Slot Allowance for Thermal Expansion—For
Commencing approximately 1 in. (25 mm) from one end of the
siding panels utilizing nail slots to allow for thermal expansion
specimens, make five measurements at 6 in. (152 mm)
and contraction, the nail slot shall be sized to allow for the
intervals, making sure that the measurement is made perpen-
expected range of expansion and contraction over a range of
dicular to the butt edge. Average the measurements. The
100°F. Compliance with this requirement shall be demon-
average constitutes the exposed width of siding.
strated either by the test method in 6.15 or by sizing of the nail
slots according to the specifications in the following sections. 6.5 Thickness shall be measured in accordance with Test
Method A of Test Method D5947. The micrometer shall be
The instrument used shall be capable of measuring to the
nearest 0.01 in. The manufacturing tolerance shall not exceed calibrated in accordance with Section 8 of Test Method D5947.
The thickness of the siding shall be measured at a minimum of
-0.030 in.
5 locations equally spaced across the entire portion of the
5.2.3.1 For panels shorter than 6 ft (1829 mm) in length, the
3 siding that will be exposed after installation. All measurements
minimum nail slot width shall be ⁄8 in. (11.4 mm).
shall be taken to the nearest 0.001 in. Calculate and report the
5.2.3.2 For panels 6 ft (1829 mm) in length or longer the
average of these measurements. Also report the thinnest
minimum nail slot width shall be determined according to the
individual measurement.
following formula. The minimum width shall be the width
resulting from application of the formula, rounded to the next 6.6 Camber—Place a full length of siding (typically 10 or
12 ft (3.05 or 3.61 m)) on a flat surface alongside a straightedge
lower quarter-inch. Regardless of the results of the calculation,
at least as long as the siding specimen. Measure the maximum
the minimum nail slot width for panels 6 feet or longer shall be
space between edge of the siding specimen and the straight-
1 in (25.4 mm).
edge for each edge to the nearest ⁄16 in. (1.6 mm).
WS 5 P × α × 100 °F × L 1T (1)
~ !
c c
6.7 Heat Shrinkage:
WS = minimum width of nail slot, in.,
6.7.1 Apparatus:
P = center-pinning coefficient: 1 if manufacturer’s instruc-
c
6.7.1.1 Scriber, similar to that described in Test Method
tions require panel to be center-pinned; 1.5 if center-
D1042, with the exception that the needle points shall be
pinning is not required,
separated by 10 6 0.01 in. (254 6 0.254 mm).
D7445 − 18
6.7.1.2 Test Media, a controlled-temperature water bath of 5 6.10.3 Samples shall be representative of the product to be
gal (10 L) or more, equipped with an efficient stirrer that will evaluated.
maintain uniform temperature throughout. Heater and
NOTE 9—Samples prepared in the laboratory in the same manner as
temperature-control devices must maintain the water at 160 6
commercial samples are permitted to be used as an alternative to a
1°F (71 6 0.5°C). Use a wire rack to raise and lower
commercial part. If the commercial product is extruded, the laboratory
specimen must be extruded; if the commercial product is injection
specimens into the water bath. As an alternative to the use of a
molded, the laboratory specimen must be injection molded, and so forth.
water bath, the specimens may be heated for 30 min in a
uniformly heated forced-air oven maintained at a temperature 6.10.4 Select a minimum of 4 specimens per sample per test
of 160 6 1°F (71 6 0.5°C).
site to allow for 3 test specimens and 1 file specimen for each
6.7.1.3 Make measurements with any device capable of sample evaluated.
measuring the distance between two scribe marks to the nearest 6.10.5 Mark each specimen permanently to ensure reten-
0.01 in. (0.254 mm).
tion of identity during and after exposure testing.
6.7.2 Procedure:
NOTE 10—Use of a vibratool leaves a permanent mark that satisfies this
6.7.2.1 Cut three specimens from the siding panel, each 1 in.
criterion.
(25.4 mm) wide by 12 in. (305 mm) long. Cut one specimen
6.10.6 All exposures shall be conducted at an angle of 45°
from the center and one from each of the extreme edges of the
South, plywood backed, in accordance with Practice D1435
flat surface. The long axis shall be parallel to the machine
and G147.
direction.
6.10.7 After a minimum of 24 months of exposure, remove
6.7.2.2 Condition specimens at 73.4 6 3.6°F (23 6 2°C)
the samples and inspect each exposed test specimen for
and 50 6 5 % relative humidity for at least 24 h.
appearance and surface condition. Record observations and
6.7.2.3 Make a slight mark with the scribe on each specimen
inspection date in a permanent record.
so that a reference point will be clearly visible.
6.11 Gloss:
6.7.2.4 Place specimens in the test medium.
6.11.1 Apparatus—Measure gloss using a 75° geometry
6.7.2.5 Remove specimens after 30 min and place on a flat
glossmeter that meets the requirements of the Apparatus
surface until cool.
section of Test Method D2457.
6.7.2.6 Repeat conditioning in accordance with 6.7.2.2.
6.11.2 Procedure:
6.7.2.7 Make a second mark with the scribe on each
6.11.2.1 Gloss measurements shall be made in accordance
specimen, using the same center.
with the procedure in Section 9 of Test Method D2457, unless
6.7.2.8 Measure the distance, D, between the scribe marks
otherwise specified herein.
to the nearest 0.01 in. (0.254 mm).
6.11.2.2 Measure gloss on one piece of siding on at least
6.7.2.9 Calculate the percent shrinkage as (D/10) × 100.
three widely separated sections across the width of the exposed
6.7.2.10 Report the average shrinkage of the three speci-
surface of the panel. At least one reading shall be taken on each
mens tested.
face of the panel. Use new surface area for each reading to
6.8 Impact Resistance—Test impact resistance of siding in
avoid scratches caused by instrument contact. The area tested
accordance with Test Method D4226, Procedure A, impactor
must be flat. If a flat area on the exposed surface cannot be
head configuration H.25. 4 in.-lb increments (0.5 in. height
found due to the style or depth of embossing of the panel being
increments with 8 lb falling weight) shall be used. Minimum
tested, then a non-exposed area of the panel shall be chosen in
sample dimensions shall be 1.5 by 1.5 in. Samples shall be
its place. Such locations shall be representative of the gloss of
tested with the normally exposed surface facing up. Backed
the area that will be exposed after installation.
siding shall be tested with any backing material removed.
6.11.2.3 Measure gloss parallel to the direction of emboss-
Conditioning time for quality-control tests shall be at least 1 h.
ing. When the embossing pattern is not apparent, measure the
6.8.1 For purposes of evaluating failure of the specimen
gloss in the direction of extrusion.
under section 3.2.1 of Test Method D4226, a ductile tear of less
6.11.2.4 Each reading shall be within the appropriate limit
than 0.2 in. (5 mm) in length shall not be considered a failure.
specified in 5.1.7.
Any brittle break of any dimensions is considered a failure.
6.11.2.5 The average reading of all readings shall be used to
6.9 Coeffıcient of Linear Expansion—Conduct this test in represent the gloss of the sample.
accordance with Test Method D696.
6.12 Surface Distortion:
6.10 Weatherability: 6.12.1 Test Specimen/Apparatus:
6.10.1 A minimum of three samples shall be exposed at each 6.12.1.1 The test specimen shall consist of three courses of
of at least three test sites. Test sites shall be located in a
backed vinyl siding, a minimum of 6 ft (1.83 m) in length,
northern temperate climate, represented by Cleveland, Ohio or mounted on a flat rigid frame in accordance with the manu-
Louisville, Kentucky; a hot, humid climate represented by
facturer’s recommended installation instructions.
Miami, Florida; and a hot, dry climate represented by Phoenix, (1) Horizontal Siding—The middle course shall consist of
Arizona. The samples shall be exposed for a minimum of 24
two lengths of backed vinyl siding, both with a factory-
months. fabricated end, one section overlapping the other section. The
6.10.2 Samples shall consist of a flat section of siding with end of the overlapping section shall be located not less than 3
minimum dimensions of 2 in. by 3 ⁄4 in. (25 mm by 95 mm). in. (76 mm) and not more than 6 in. (152 mm) from the center
D7445 − 18
of the course. Unless specified otherwise by the manufacturer’s agreed upon color coordinates for that specific color product in
installation instructions, the insulation of the two lengths of accordance with Test Method D2244. Calculate the total
backed vinyl siding shall be butted firmly together.
difference ΔE between the production specimen and the refer-
(2) Vertical Siding—The middle course shall consist of a
ence specimen in accordance with Test Method D2244.
single, uninterrupted backed vinyl siding panel, without over-
6.14 Wind Load Resistance—Conduct the test on wind load
lap.
resistance of finished siding in accordance with Test Method
6.12.1.2 A thermocouple or other heat-sensing element shall
D5206. The average maximum sustained static test pressure
be located at the horizontal midpoint of the backside of the
determined from this testing is used in 5.2.2. For purposes of
middle course of backed vinyl siding. The heat-sensing ele-
determining compliance with the minimum test pressure and
ment shall be in contact with the back of the vinyl cladding.
standard design pressure requirements in 5.2.2, the test struc-
Any backing material removed to facilitate placement of the
ture shall be constructed with vertical studs 16 in. on center.
heat sensing element shall be replaced.
The siding shall be tested with the foam plastic backing
6.12.1.3 Radiant-Heat Rod, 600 W for each linear foot (0.31
attached to the vinyl siding. The siding in the test installation
m), mounted parallel to the middle course and approximately
shall be installed over wood sheathing with a nominal thick-
32 in. (810 mm) away from the surface of the backed vinyl
7 1
ness of ⁄16 to ⁄2 in., and fastened as follows:
siding.
6.12.1.4 Temperature-Control Device, used to regulate the 6.14.1 Fastener type—Roofing nail, smooth shank, 0.120 in.
1 5
temperature of the radiant-heat rod, shall be able to maintain
( ⁄8 in. nominal; 3.2 mm) shank diameter, ⁄16 in. (7.9 mm) head
the conditions specified in 6.12.2.1.
diameter, length as necessary to penetrate into sheathing and
6.12.1.5 Gap Measurement Device—A cylindrical pin
stud a total of 1 ⁄4 in. (32 mm). For vertical siding, length as
gauge, ⁄4 6 0.005 in. (6 6 0.127 mm) in diameter is used to
necessary to penetrate the thickness of the sheathing plus ⁄4 in.
evaluate the size of any gap in the overlapped sections of
(6.4 mm).
horizontal backed vinyl siding during the heating period. The
6.14.2 Fastener Spacing—Every 16 in. (406 mm) into
pin gauge is attached to a rod such that the gauge can be
center of stud for horizontal siding. For vertical siding, every
inserted into a gap while held parallel to the plane of the
12 in. into sheathing only.
backed vinyl siding. The rod shall be sufficiently long to permit
6.14.3 Fasteners shall not be driven tightly against the
insertion of the gauge from beyond the edge to the test frame,
siding. Allow approximately ⁄32 in. (0.8 mm) clearance be-
not interfere with the exposure of the sample to radiant heat,
tween the fastener head and siding surface.
and otherwise not interfere with conduct of the test.
6.12.2 Procedure:
NOTE 11—The installation details described 6.14 conform to the
6.12.2.1 Heat the test panel (middle course of backed vinyl
minimum requirements of the 2015 International Residential Code and the
siding) at a rate of 3.0 to 6.0°F/min (1.7 to 3.3°C/min) until a VSI Vinyl Siding Installation Manual.
minimum temperature of 150°F (66°C) is achieved as mea-
6.15 Nail Slot Allowance for Thermal Expansion—As an
sured by the heat-sensing element on the midpoint of the
alternative to conformance with the nail slot width specifica-
backside of the middle course. For temperatures equal to or
tion in 5.2.3.1 or 5.2.3.2, provision for thermal expansion and
greater than 130°F (54°C), the rate of heating is permitted to be
contraction shall be demonstrated through the following test
not less than 2.0°F/min (1.1°C/min), provided that the average
procedure.
heating rate from the ambient temperature to 150°F (66°C) is
6.15.1 Samples—At least 3 samples of each profile in which
within 3.0 to 6.0°F/min (1.7 to 3.3°C/min). When a tempera-
the siding is produced shall be provided. The length of each
ture of 150°F (66°C) is attained, shut off the heat source.
sample shall be at least 50 % of the longest length in which the
6.12.2.2 During this heating period, observe the middle
profile is produced, and not shorter than 12 ft (3658 mm).
course of the backed vinyl siding for surface distortion and
observe for any opening or gap at the end of the overlapped 6.15.2 Test Chamber—The test chamber shall consist of an
section. If the overlap appears to have opened to approximately
environmentally controlled room or compartment capable of
⁄4 in. (6 mm), attempt to insert the gap measurement device
providing an air temperature range of at least 0°F to 100°F
into the opening. If the device can be inserted in to the opening
(-18°C to 38°C) without exposure of the panel to radiant
to any depth at any location along the overlap, the opening
energy from heating or cooling elements. Air temperature shall
shall be considered to be at least ⁄4 in. (6 mm).
be controlled such that a rate of temperature change of 2°F
6.12.2.3 Failure is defined as:
(1.11°C) per minute can be achieved over the full temperature
(1) the appearance of bulges, waves, or ripples on any
range, and the minimum and maximum temperatures can be
surface of the middle course of the backed vinyl siding;
maintained for at least 15 minutes. Means for circulating air to
(2) occurrence of a gap or opening ⁄4 in. (6 mm) or greater
provide a uniform air temperature throughout the chamber
at any point along the end of the overlapped section, as
shall be provided. A vertical wall shall be provided for
determined by use of the gap measurement device, at any time
mounting of samples. The wall shall be insulated such that,
or before a temperature of 150°F (66°C) is reached.
with no panels mounted, the inner surface of the wall does not
6.13 Color Uniformity—Calculate the difference between deviate more than 10°F (5.5°C) from the air temperature at the
high and low temperature extremes after a holding period of 5
the L , a , and b color coordinates for a production specimen
H H H
to those of either the appropriate reference specimen or the minutes. The test chamber shall be of sufficient size to
D7445 − 18
accommodate the longest panel to be tested, including ex- require the panel to be center-pinned, the result of E + 0.25 in.
t
pected thermal expansion of the panel. Means shall be pro- for each of the 3 samples for each profile shall not be greater
vided to measure the actual temperature of the surface of each than the width of the nail slot.
panel at a minimum of 3 evenly-spaced locations along the
6.16 Lead Content:
length of the panel.
6.16.1 Testing for lead content shall be conducted on backed
6.15.3 Length Measurement—A means for measuring the
vinyl siding using a rhodizinate-type lead swab test kit con-
length of each sample throughout the temperature range shall
forming to Practice E1753. Testing shall be performed in
be provided. The method utilized for length measurement shall
accordance with the test kit manufacturer’s instructions. The
not be influenced by the temperature of the chamber and shall
backed vinyl siding shall be deemed to comply with 4.7 if the
have a minimum resolution of no greater than 0.0625 in. (1.59
test shows a negative or not-detected result; that is, the test
mm).
does not indicate the presence of lead. The test shall be
6.15.4 Procedure—Install the sample panels on the wall
conducted separately on the substrate and on any cap or film
inside the test chamber, following the manufacturer’s instruc-
material.
tions for fastener type, spacing, location and tightness. At
6.16.2 As an alternative to the method in 6.16.1, and as a
ambient temperature measure and record the length of each
means of resolving any ambiguous results from that method, an
panel and the temperature of the panel, averaged from a
analytical method capable of detecting lead at least as low as
minimum of 3 locations along the length of the panel.
0.02 percent by sample weight shall be employed. Under this
6.15.4.1 Test Cycle—Test cycles shall be performed by alternative, neither the substrate nor any cap or film shall
raising the air temperature to 100°F 6 5°F (38°C 6 2.75°C) at
contain a concentration of lead in excess of 0.02 percent by
an average rate of 2°F (1.11°C) per minute, holding the air weight.
temperature at 100°F (38°C 6 2.75°C) for 15 minutes,
7. Packaging and Package Marking
lowering the air temperature to 0°F 6 5°F (-18°C 6 2.75°C) at
an average rate of 2°F (1.11°C) per minute, holding at 0 °F
7.1 The siding shall be packed in such a manner as to
(-18°C 6 2.75°C) for 15 minutes, and returning to ambient
provide reasonable protection against damage in ordinary
temperature at an average rate of 2 °F per minute.
handling, transportation, and storage.
6.15.4.2 Conditioning—Close the test chamber and perform
7.2 Provisions of Practice D3892 shall apply to this
at least 2 conditioning cycles using the procedure in 6.15.1. No
specification.
interruption is required between conditioning cycles.
7.3 To aid identification of siding conforming to all require-
6.15.4.3 Test—Following completion of the conditioning
ments of this specification, producers and distributors shall
cycles, conduct 3 test cycles using the procedure in 6.15.4.1. It
include a statement of compliance in conjunction with their
is acceptable for the test cycles to follow immediately upon
name and address on product labels, invoices, sales literature,
completion of the final conditioning cycle, and no interruption
and the like. The following statement is suggested when
is required between test cycles. After a minimum holding
sufficient space is available:
period of 15 minutes at the high and low extremes of each test
This PVC siding conforms to all the requirements estab-
cycle, measure and record the length of each panel and the
lished in ASTM Specification D7445, developed cooperatively
temperature of the panel, averaged from a minimum of 3
with the industry and published by ASTM.
locations along the length of the panel.
Full responsibility for the conformance of this product to the
6.15.5 Normalization—From among the length measure-
specification is assumed by (name and address of producer or
ments recorded for all three cycles, identify the shortest and
distributor).
longest length of each panel, and the average panel temperature
7.4 The following abbreviated statement is suggested when
at the time that length was recorded. Determine the maximum
available space on labels is insufficient for the full statement:
difference in length, ΔL, and the maximum difference in
Conforms to ASTM Specification D7445 (name and address of
temperature, ΔT, by subtracting the smaller from the larger.
producer or distributor).
Normalize the change in length to the full length of the panel
over a 100 °F (38 °C) temperature range using the following
7.5 The standard wind load design pressure rating deter-
formula:
mined in accordance with 5.2.2.2 shall be stated on the product
or on the product package by one of the means in 7.5.1 or 7.5.2.
E 5 ΔL × 100/ΔT × L /L (2)
~ ! ~ !
t f t
7.5.1 The package shall be marked or labeled with the
E = total thermal expansion and contraction of a full length
t
standard wind load design pressure rating. The marking shall
panel over a range of 100°F (38°C),
be in the format “Standard Wind Load Design Pressure Rating:
ΔL = maximum change in length of the tested panel,
##.# psf (ASD)”.
ΔT = maximum change in temperature of the tested panel,
7.5.2 The standard design pressure rating shall be included
L = longest length in which the panel is produced, and
f
on a line imprint or other marking on the front (outward-
L = actual length of the panel as tested.
t
facing) surface of all siding panels. It is not required that the
6.15.6 Acceptable Performance—When tested according to marking be visible after installation, provided that the marking
this procedure, the result of (E × 2) + 0.25 in. for each of the can be revealed and read by detaching the lower edge lock of
t
3 samples for each profile shall not be greater than the width of an adjacent course, without removal of any fasteners. The
the nail slot. If the manufacturer’s installation instructions standard design pressure marking shall be stated at least once
D7445 − 18
per panel. The marking shall be in the format “Std Design wall configuration for which it is applicable, and shall refer to
Pressure Rating: ##.# psf (ASD)”. the manufacturer’s instructions for more information and any
7.5.3 At the option of the manufacturer, additional marking
installation requirements.
or labeling of the package or product with alternative wind load
design pressure ratings determined in accordance with 5.2.2.3
8. Keywords
for use with alternative sheathings, wall configurations or
8.1 plastic building products; plastic weatherability; re-
fastening methods is permitted. The marking shall use the
cycled plastic; rigid PVC siding; specification
format specified in 7.5, shall indicate the type of sheathing or
ANNEX
(Mandatory Information)
A1. WIND LOAD RESISTANCE TEST DESIGN FACTORS
A1.1 Wind Load Criteria:
I = “importance factor” as described in editions of ASCE 7
prior to ASCE 7-10. A value of 1.0 is used. This factor
A1.1.1 ASCE 7-10 is the basis for determining the design
is not used where the wind speed has been determined
pressures used in this specification. Design wind loads are
from a map in ASCE 7-10. (See Note A1.4.)
determined on an ASD basis in this specification.
K = “velocity pressure coefficient” as described in ASCE
z
NOTE A1.1—In previous editions of ASCE 7, wind loads were deter-
7-10. A “K ” of 0.70 was used in the wind pressure
z
mined using wind speed maps based on a 50-year return period. In ASCE
calculations, which is the value from ASCE 7-10 for a
7-10, maps based on a 700-year return period are used which, for any
mean roof height of 30 ft (9.1 m) above ground level
given location, produce a wind speed approximately 30 % greater than
that of the previous maps. This larger magnitude (higher return period) and Exposure Category B.
wind speed, referred to as the ultimate wind speed, (V ), is used directly
ULT K = “wind directionality factor” as described in ASCE
d
(with a load factor of 1.0) to determine nominal wind loads on a Strength
7-10. A “K ” of 0.85 is used.
d
Design (LRFD) or “ultimate” wind load basis. When Allowable Stress
Design (ASD) is used, ASCE 7-10 provides for these ultimate wind loads,
A1.1.4 Thus, for the given velocity and factors, the velocity
determined from the ultimate wind speed map velocities, to be multiplied
pressure = 18.43 lbf/ft (882 Pa).
by a load factor of 0.6. Alternatively, the adjustment can be made directly
to the wind velocity, which is the approach taken in this method (se
...