ASTM D6662-01
(Specification)Standard Specification for Polyolefin-Based Plastic Lumber Decking Boards
Standard Specification for Polyolefin-Based Plastic Lumber Decking Boards
SCOPE
1.1 This specification covers polyolefin-based plastic lumber products for use as exterior residential decking boards.
1.2 Plastic lumber products are currently made predominantly with recycled polyolefin plastics (in particular high-density polyethylene) where the products are more or less non-homogenous in the cross-section. However, this specification may also be applicable to similar manufactured plastic products made from other plastic and plastic composite materials that have non-homogenous cross-sections.
1.3 This specification details a procedure to calculate recommended span lengths for spacing of support joists. This procedure was developed using experimental data from a typical unreinforced plastic lumber made predominantly from recycled high-density polyethylene. The methodology to develop span lengths for other types and compositions of plastic lumber is detailed in Appendix X1 of this standard.
1.4 The values are stated in inch-pound units, as these are currently the most common units used by the construction industry. Equivalent SI units are indicated in parentheses. However, the units stated for irradiance exposure in the weatherability section (6.3) are in SI units as these are the units commonly used for testing of this type.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.Note 1--There is no similar or equivalent ISO Standard.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D 6662 – 01
Standard Specification for
Polyolefin-Based Plastic Lumber Decking Boards
This standard is issued under the fixed designation D 6662; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope D 2915 Evaluating Allowable Properties for Grades of
Structural Lumber
1.1 This specification covers polyolefin-based plastic lum-
D 4329 Practice for Operating Light and Water Apparatus
ber products for use as exterior residential decking boards.
(Fluorescent UV and Condensation Type) for Exposure of
1.2 Plastic lumber products are currently made predomi-
Plastics
nantly with recycled polyolefin plastics (in particular high-
D 5033 The Development of Standards Relating to the
density polyethylene) where the products are more or less
Proper Use of Recycled Plastics
non-homogenous in the cross-section. However, this specifica-
D 6109 Test Method for Flexural Properties of Unrein-
tion may also be applicable to similar manufactured plastic
forced and Reinforced Plastic Lumber
products made from other plastic and plastic composite mate-
D 6112 Test Methods for Compressive and Flexural Creep
rials that have non-homogenous cross-sections.
and Creep-Rupture of Plastic Lumber and Shapes
1.3 This specification details a procedure to calculate rec-
D 6341 Test Method for Determination of Thermal Expan-
ommended span lengths for spacing of support joists. This
sion of Plastic Lumber and Plastic Lumber Shapes Be-
procedure was developed using experimental data from a
tween -30 °F and 140 °F (-34 °C and 60 °C)
typical unreinforced plastic lumber made predominantly from
E 84 Test Method for Surface Burning Characteristics of
recycled high-density polyethylene. The methodology to de-
Building Materials
velop span lengths for other types and compositions of plastic
E 108 Test Methods for Fire Tests of Roof Coverings
lumber is detailed in Appendix X1 of this standard.
G 151 Practice for Exposing Nonmetallic Materials in ac-
1.4 The values are stated in inch-pound units, as these are
celerated Test Devices that Use Laboratory Light Sources
currently the most common units used by the construction
G 154 Practice for Operating Fluorescent Light Apparatus
industry. Equivalent SI units are indicated in parentheses.
for UV Exposure of Nonmetallic Materials
However, the units stated for irradiance exposure in the
G 155 Practice for Operating Xenon Arc Light Apparatus
weatherability section (6.3) are in SI units as these are the units
for Exposure of Non-Metallic Materials
commonly used for testing of this type.
1.5 This standard does not purport to address all of the
3. Terminology
safety concerns, if any, associated with its use. It is the
3.1 Definitions:
responsibility of the user of this standard to establish appro-
3.1.1 plastic lumber, n—a manufactured product composed
priate safety and health practices and determine the applica-
of more than 50 weight percent resin, and in which the product
bility of regulatory limitations prior to use.
generally is rectangular in cross-section and typically supplied
NOTE 1—There is no similar or equivalent ISO Standard.
in sizes that correspond to traditional lumber board and
dimensionallumbersizes,maybefilledorunfilled,andmaybe
2. Referenced Documents
composed of single or commingled resins.
2.1 The following documents of the issue in effect on the
3.1.2 resin, n—a solid or pseudo solid organic material
dateofmaterialpurchaseformapartofthisspecificationtothe
often of high molecular weight, which exhibits a tendency to
extent referenced herein:
flow when subjected to stress, usually has a softening or
2.2 ASTM Standards:
melting range, and usually fractures conchoidally. (See Termi-
D 883 Terminology Relating to Plastics
nology D 883.)
D 2565 Practice for Xenon Arc Exposure of Plastics In-
3.1.2.1 Discussion—In a broad sense, the term is used to
tended for Outdoor Applications
designate any polymer that is a basic material for plastics.
(1982)
This specification is under the jurisdiction of ASTM Committee D20 on
PlasticsandisthedirectresponsibilityofSubcommitteeD20.20onPlasticProducts. Annual Book of ASTM Standards, Vol 04.10.
Current edition approved April 10, 2001. Published July 2001. Annual Book of ASTM Standards, Vol 08.03.
2 6
Annual Book of ASTM Standards, Vol 08.01. Annual Book of ASTM Standards, Vol 04.07.
3 7
Annual Book of ASTM Standards, Vol 08.02. Annual Book of ASTM Standards, Vol 14.04.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D6662–01
3.2 Definitions of Terms Specific to This Standard:
Nominal (in.) Actual (in.) Tolerance (in.)
3 1
1 ⁄4 6 ⁄16
3.2.1 bulge—convex distortion (away from the center of the
5 1
⁄4 1 6 ⁄16
cross-section) of the face of the board from a straight line
1 1
21- ⁄2 6 ⁄16
drawn from edge to edge across the width of the board.
Tolerance on thickness of boards thicker than 2 inches
3.2.2 crook—distortion of the board in which there is a
(nominal) shall be 6 ⁄16 inch.
deviation in a direction perpendicular to the edge from a
5.2 Width of Boards—Unless otherwise specified in para-
straight line from end to end of the board.
graph 4.1.7, board widths shall be:
3.2.3 cup—concave distortion (towards the center of the
Nominal (in.) Actual (in.) Tolerance (in.)
cross-section) of the face of the board from a straight line
1 1
32- ⁄2 6 ⁄16
drawn from edge to edge across the width of the board.
1 1
43- ⁄2 6 ⁄16
1 1
3.2.4 edge—the side of a rectangular-shaped board corre- 65- ⁄2 6 ⁄16
1 1
87- ⁄4 6 ⁄16
sponding to the thickness of the board.
1 1
10 9- ⁄4 6 ⁄16
3.2.5 face—the side of a rectangular-shaped board corre- 1 1
12 11- ⁄4 6 ⁄16
sponding to the width of the board.
Toleranceonwidthofboardswiderthan12inches(nominal)
3.2.6 thickness—the lesser dimension of the cross-sectional
shall be 6 ⁄16 inch.
profile of a rectangular-shaped board.
5.3 Length of Boards—unless otherwise specified in 4.1.6,
3.2.7 width—the greater dimension of the cross-sectional
1 1
boards up to 20 feet shall have tolerances of + ⁄2 inch or - ⁄16
profile of a rectangular-shaped board.
1 1
inch. Over 20 feet, the tolerances will be + ⁄2-inch or - ⁄16 inch
3.3 Additional definition of terms applying to this specifi-
per 20-ft of length or fraction thereof. Measurement of lengths
cation appear in Terminology D 883 and D 5033.
to be made at 73 6 2 °F and relative humidity of 50 65%.
5.4 Flatness Tolerance—Board shall be flat with maximum
4. Ordering Information
cup or bulge in the board face limited to the tolerances inTable
4.1 The information contained in this specification is in-
1. Linear interpolation of the values is acceptable for dimen-
tended to be helpful to producers, distributors, regulatory
sions other than listed.
agencies and users. The information can also promote under-
5.5 Squareness—Unless a specially shaped member is
standing between purchasers and sellers. The purchaser shall
specified, the cross-section of all boards shall be visually
state whether this specification is to be used, select the
rectangular (that is, the face and edge of the board are
preferred options permitted herein, and include the allowable
perpendicular to each other) and suited for the intended
design information in the invitation to bid and purchase order
purpose.
from the following:
5.6 Crook—Crook shall conform to the tolerances in Table
4.1.1 Title, number and date of this specification,
2. Linear interpolation of the values is acceptable for dimen-
4.1.2 Minimum allowable bending strength and allowable
sions other than listed.
bending stiffness,
5.7 Tongue and Groove—Boards shall be without tongue
4.1.3 Percent recycled content (if requested),
andgrooveunlessotherwisespecifiedin4.1.7.Becauseofload
4.1.4 Color,
transfer between adjacent boards, the methodology and equa-
4.1.5 Quantity in lineal feet,
tions presented in section 6.1.4 for determining recommended
4.1.6 Cut length,
maximumspanlengthsarenotapplicabletotongueandgroove
4.1.7 Cross-sectional dimensions,
boards. Manufacturers of tongue and groove decking boards
4.1.8 Packing requirements,
shall provide recommended span lengths based on sound
4.1.9 Palletization, if required,
engineering practice, taking into account some of the issues
4.1.10 Marking, if other than specified.
described in 6.1.4 below, as well as previous, in-service
4.2 If specific mechanical property values are not required
performance history.
by the purchaser (for example, when purchasing materials for
general retail sales distribution and not for a specific project), 6. Performance Requirements
the manufacturer shall provide minimum allowable design
6.1 Flexural Properties:
information, as would be determined under this specification,
6.1.1 Test Procedure—D 6109.
to aid in the application of the decking board material by the
6.1.2 Specimens Tested—Aminimum of 15 specimens shall
end user.
be tested.
6.1.3 Criteria—(1) The mean value of the secant flexural
5. Dimensions and Permissible Variations
modulus at 1 % outer fiber strain estimated statistically to
within 5 % with 75 % confidence shall equal or exceed 50 000
Decking boards may be produced either in sizes which
psi. Table 3 shows the number of specimens required to
subscribe to the standard dimensions of the wood industry, or
to proprietary dimensions designed by manufacturers. This
specification does not limit the dimensional range that may be
TABLE 1 Cup or Bulge Tolerances Relative to Nominal Width of
produced by manufacturers. For reference, the standards of the
the Board Face
wood industry are as follows:
Face Width, in. #4 in. 6 in. 8 in. 10 in. 12 in.
5.1 Thickness—Unless otherwise specified in 4.1.7, boards
1 1 1 3 1
Tolerance ⁄32in. ⁄16in. ⁄8in. ⁄16in. ⁄4in.
shall be:
D6662–01
TABLE 2 Crook Tolerances Relative to Nominal Length and
Width of the Board
Length in Feet #4 in. Width 6 in. Width 8 in. Width 10 in. Width 12 in. Width
3 1 3 1 1
4–6 ⁄8in. ⁄4in. ⁄16in. ⁄8in. ⁄8in.
1 1 3 1 3
8 ⁄2in. ⁄2in. ⁄8in. ⁄4in. ⁄16in.
3 5 1 7 3
10 ⁄4in. ⁄8in. ⁄2in. ⁄16in. ⁄8in.
7 13 3 9
12 1 in. ⁄8in. ⁄16in. ⁄4in. ⁄16in.
1 1 7 3
14 1 ⁄4in. 1 ⁄8in. 1 in. ⁄8in. ⁄4in.
1 3 1 7
16 1 ⁄2in. 1 ⁄8in. 1 ⁄8in. 1 in. ⁄8in.
FIG. 1 Schematic of Concentrated Load on Boards that are
Continuous Over Two Spans
TABLE 3 Number of Specimens Required to Establish the Mean
Value with an Error of 6 5 % with 75 % Confidence for Various
Coefficients of Variation (COV) in the Data Set
either the stress or the deflection formula as follow, whichever
provides the lesser span:
COV Range, % 10–15 >15–20 >20–25 >25
No. of Specimens, N 15 23 34 ~60
Stress Formula:
L 5 ~64SF 8!/~13P! (1)
b
Deflection Formula:
establish the mean value at 75 % confidence interval with 6
L 5 @~67E8I!/~Pka!# (2)
5 % error using Practice D 2915. (2) The 5 % lower tolerance
limit at 75 % confidence flexural stress at 3 % outer fiber strain
For distributed (or uniform) loads on boards which are
shall equal or exceed 1000 psi. If any specimen fails prior to
continuous over a minimum of two spans (such as decking
reaching 3 % strain, then the flexural strength at failure for that
boards) as shown in Fig. 2, the maximum span shall be limited
specimen shall equal or exceed 1000 psi. The 5 % lower
by either the stress or the deflection formula as follow,
tolerance limit at 75 % confidence is computed by subtracting
whichever provides the lesser span:
K-times the standard deviation from the mean value, where K
Stress Formula:
is tabulated in statistics handbooks (and in Table 3 of Practice
D 2915) as a factor for a one-sided tolerance limit for the L 5 @~8SF 8!~144!/~qb!#2 (3)
b
distribution. Table 4 shows the value of K for several sample
Deflection Formula:
sizes.
L 5 @~185E8I!~144!/~qb ka!#3 (4)
NOTE 2—Many standards require a minimum sample size of approxi-
mately 30 to balance testing costs against the large reductions in the
where:
allowable values for very small sample sizes.
L = computed span length, in.,
NOTE 3—A16 in. on center joist spacing is considered typical standard
S = section modulus, in. ,
spacing for residential deck construction. While 50 000 psi is given as a
F 8 = allowable flexural stress as computed in 6.1.4.1, psi,
minimum flexural modulus, a modulus greater than 50 000 psi may be
b
P = concentrated load, lb,
required for some decking board sizes in order to meet this spacing when
determining span lengths per the guidance presented in 6.1.4 below. E8 = effective modulus of elasticity as computed in
Alternatively, span lengths less than 16 in. on center may be used as
6.1.4.2, psi,
needed.
I = moment of inertia, in. ,
NOTE 4—ConcurrenttothedevelopmentofthisspecificationforPlastic
k = factor used to limit deflection to L/k (for example
Lumber Decking, a Standard Guide for the Design and Construction of
L/360 with k = 360; or L/120 with k = 120),
Plastic Lumber Decking is being developed by Section D20.20.01 (under
q = uniformly distributed load, lb/sq-ft,
the Subcommittee D20.20 on Plastic Products). This Standard Guide is
b = actual board width, in., and
expected to be available sometime after this Specification has been
a = Creep Adjustment Factor = 1.5.
approved and in use.
NOTE 5—The attached commentary in Appendix X1 provides a ratio-
6.1.4 Span Lengths—Recommended maximum span
nale for the Creep Adjustment Factor, a.
lengths shall be determined using the following equations:
For concentrated loads on boards which are continuous over
a minimum of two spans (such as decking boards) as shown in
Fig. 1, the maximum recommended span shall be limited by
TABLE 4 Value of K for Establishing the Lower 5 % Lower
Tolerance Limit with 75 % Confidence for Various Sample Sizes
No. of Specimens, N 15 30 Infinite
FIG. 2 Schematic of Distributed Load on Boards that are
Value of K 1.991 1.869 1.645
Continuous Over Two Spans
D6662–01
TABLE 5 Load Duration Factor, C
6.1.4.1 Allowable Flexural Stress—The allowable flexural
D
stress, F 8, of the decking board is given as follows: Duration of Load Load Duration Factor
b
Impact Load—1 s 4.81
F 8 5 ~F /FS!· C · C (5)
b b D T
1 min 3.62
3 min 3.34
where:
Wind/Seismic Load—10 min 3.04
F = the base flexural stress value for plastic lumber made
b 1 h 2.64
of HDPE-type polyolefins for normal duration load- 6 h 2.28
1 day 2.04
ing (10 yr. duration), psi,
Construction Load—7 days 1.73
FS = Factor of Safety = 1.5,
Snow Load—2 months 1.44
C = Load Duration Factor for flexural stress, presen
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.