is a single member sizing solution that allows users to size floor and roof joists, beams and posts by inputting span and load information. Innovative tools allow selection of the most cost effective solution.

If you’re an isPlan® user you can easily choose any member in your model and send it right into isDesign® to review job site changes or repairs. All loads and information will transfer into the isDesign® member calculations.

isDesign® provides all the features expected in a current design application and since all manufacturers are available eliminates the need for multiple applications.




multiply and link loads


The isDesign® interface features an interactive member diagram that allows users to manipulate the model using the mouse. Users can change depth, length, add or change supports and even add holes right in the model.

All editable user inputs are right on one screen eliminating the need to switch back and forth between different input screens.

iStruct®’s Project feature allows users to manage all member designs and project documents and plans in a single location.



holes in beams


isDesign® will design members using either ASD or LSD criteria to meet U.S. and Canadian building codes. Users can manually add uniform, concentrated and moving loads to the member as well as link reactions from other isDesign® members. Fasteners can also be designed for mutiply members including requirements for concentrated side loads.

Design different hole shapes in joists and beams. Repairs are easy using the location analysis tool to find shear and moment results at any location along the member. isDesign® can also check notches and sloped end cuts in beams.

Users can set custom deflection criteria as well as custom load duration factors for any live load.



Project view


It’s easy to generate material quotes with pricing right from the project. Batch print all calculations into a single pdf package. Users can choose between a simple one page report or print entire shear and moment diagrams or results from all load cases

Defaults for joist, beam and glulam designs can be saved for re-use saving time on future projects.

Available Products

  • S-P-F Lumber
  • Doug Fir Lumber
  • Southern Pine Lumber (ASD Only)
  • Steel Beams (ASD Only)
  • Ainsworth
  • Canfor / Anthony Forest Products
  • Barrette Structural (TriForce)
  • BlueLinx
  • Boise Cascade
  • Boozer Beam
  • Eacom Lumber Corp
  • EmerCor
  • Forex
  • Global LVL Inc
  • International Beam
  • Lamco
  • Louisiana Pacific
  • Metsa Wood
  • MiTek (fasteners)
  • MLT Ultralam
  • Murphy Co
  • Nordic
  • Pacific Woodtech
  • PinkWood
  • RedBuilt
  • Rosboro
  • Roseburg
  • Simpson Strong Tie (hangers and fasteners)
  • Stark
  • Stora Enso
  • USP (hangers)
  • West Fraser
  • Wesure columns (LSD Only)
  • Weyerhaeuser (Trus Joist)
  • Weyerhaeuser (EverEdge)

System Requirements

Recommended Desktop:

  • Windows 10 64bit OS
  • 3 Ghz Processor or more (i7)
  • RAM Memory of 8 GB or more
  • Hard Disk free space of 500 MB or more
  • Monitor with a resolution of 1680 x 1050 or higher
  • Monitor size of at least 24″ or larger
  • Dual monitors are a plus
  • High Speed Internet access

Recommended Laptop:

  • Windows 10 64bit OS
  • 2.3 Ghz Processor or more (i7)
  • RAM Memory of 8 GB or more
  • Hard Disk free space of 500 MB or more
  • Video processor with dedicated video memory
  • Support resolution of 1368 x 768 or higher
  • High speed internet access

Minimum Requirements:

  • Windows 7 or Windows 8.1
  • 2 Ghz Processor or more (i3)
  • RAM Memory of 2 GB or more
  • Hard Disk free space of 250 MB or more
  • Monitor with a resolution of 1360 x 768 or higher
  • CD-ROM/DVD Drive or Internet Access

isDesign® – Single Member Sizing Solution