Design tools can help customers with lumber choices

qELECTING the right western lum\Jber product for a construction project can be a daunting task, even for seasoned design professionals. Two software design tools can make that job easier, allowing wholesalers and retailers to help their customers make the right choice.

The Western Lumber Design Suite and the new Lumber DesignEasv- can deliver information on western lumber grades, spans and other technical information with just a few clicks. The two design tools, which work in concert with Microsoft Excel, are available free of charge from Western Wood Products Association.

The Western Lumber Design Suite is a full-featured design tool that provides calculations for horizontal framing (beams and joists), vertical framing (posts and studs) and wood-towood shear connections. Calculations are available for the major sizes and grades of western lumber products available in the market today. All calculations follow the 2001 National Design Specification for Wood Construction.

The Design Suite features three modes: Beam/Joist Design, Post/Stud Design, and Wood-to-Wood Single Shear Connections. The Beam/Joist mode is for horizontal framing and calculates reactions. shear. stresses. moments and deflections based on the specified loads. Users select the design parameters, and the program assigns appropriate adjustment factors and determines whether the specified member size is adequate. Also displayed are diagrams, bending moments. horizontal shear and deflec- tion per the specified loads, all on one screen.

For vertical framing. the PosVStud Design mode calculates compressive stress, bending stress. and combined stress ratio based on the specified loads for posts or studs. Users select the design parameters and the program determines whether the specified member size is adequate. Adjustment factors for load duration, size. wet use. bearing area. repetitive member, stability, incising, high temperature, column stability, flat use, and form can be specified.

The Connections mode calculates the single shear capacity of a nail, bolt. rvood screw or lag screrv connecting two rvood members. Load duration. connector penetration. and rvood member end grain conditions are considered. The calculations are only for simple connections.

While created for professional engineers and designers, the Deslgn Saite allorvs distributors to better serve their customers by providing product recommendations based on the structural requirements in the plans. Retailers using the Design Suite can identify the right species. size and grade of western lumber for a project that they can supply from inventory.

WWPA also offers a companion program Lumber DesignEasr.

Streamlined for ease of use. Lumber DesignEasv quickly calculates simple joist and rafter spans for rvestern lum-