SPECIFICATIONS FOR

STRUCTURAL PLASTIC LUMBER

DESCRIPTION:

Structural plastic lumber shall be manufactured with HDPE and fiberglass elements to act reinforcing with the HDPE. Lumber shall be molded in one piece per specified size.  All materials will have UV additives to prevent deterioration of the plastic lumber from exposure to UV light.  HDPE will be made up of no less than 80% recycled material; both post industrial and post consumer.  Finished plastic lumber will not rot, split, crack or splinter for a minimum of 50 years.  It shall be resistant to termites, marine borers, salt spray, oil, and fungus.

MECHANICAL PROPERTIES:

DIMENSIONAL TOLERANCES:

The above listed are specifications for plastic lumber to be used as a reference for bid specifications. This is only a guide.  Your specific application should be addressed by a professional engineer.

 8/31/04

Structural Plastic Lumber

Installation Guide

1.      Structural Ability

Structural Plastic lumber is recommended for structural use but care needs to be used in the design of the structure.  In most cases the deflection will control the needed size of boards.  We have span charts that can be used to determine the correct size for normal decking applications.  If you have other applications please consult with us or a qualified engineer or architect so he can take into account the long term creep and deflection issues with Structural  plastic lumber. 

2.      Expansion/Contraction

Structural plastic lumber expands and contracts along its length based on temperature.  A calculation of change in length in inches, can be done by using 0.000034 IN/IN/deg F multiplied by its length in inches and the temperate change of the board.

This expansion and contraction on short lengths is minimum but if you are using longer lengths and in a climate with large temperature changes you need to take in account the expansion / contraction of the board in the design.

3.      Fastening

When fastening using self tapping deck screw of size #8 or less through the thickness of a 2 x boards you do not need to pre drill holes.  If not predrilled, a plastic mushroom forms at the screw head and can be pounded with a hammer to cover the screw head. All fasteners should be at least 3/4" from edge or end of the board.  If a screw size over #8 is required pre-drilling is recommended.  Each deck board should be fastened with at least 2 screws per joist.  Stainless steel fasteners are recommended. 

4.      Butt Joints

When butting Structural plastic lumber against any wall, fixed surface or other boards (if necessary), they should be securely fastened to the nailer or double joist with a gap allowing for expansion.  The size of gap should be determined based on weather conditions at the time of installation – the closer the temperature is to the usual high temperature for the year, the smaller the gap.  (See chart below). The deck should be designed to minimize the butt joints.  However, in the event that joints are required, a double joist underneath the butt joint should be used.  Boards should be securely fastened with a row of screws on each side of the joint, 1” from end of the board.  Always keep deck boards out 1/4” from permanent structure.

5.      Rip Cutting

Rip cutting is not recommended on any plastic lumber.  Much of the strength of the board is on the outside surface of the boards.  Ripping boards can cause the boards to warp or curl. 

Should there be any questions regarding these instructions, please contact your sales representative for more details.

*Failure to follow these instructions will void all warranties.