This calculator allows you to find the maximum beam span or post spacing of specified Ironwoods species for your deck.

  1. Stringer Spacing is at 24″ on center (o.c.).
  2. All loads and load combinations are determined using ASCE 7. DL = Dead Load, LL = Live Load, SL = Snow Load, WLg = Wind Load, & WLu = Uplift Wind Load.
  3. Maximum total load (TL) determined from the governing case of the following:
    • TL = DL + LL
    • TL = DL + SL
    • TL = DL + 0.75*LL + 0.75*SL
    • TL = 0.6*DL + 0.6WLu
  4. Loads utilized for the table are as follows: DL = results of the calculator, LL = 100 psf or 500 psf, SL+WLg = 20 psf, where absolute uplift wind load (WLu) is not greater than WLg.
  5. Deflection limits for stringer and beams are determined as follows:
    1. Stringer – Live load deflection is limited to L/360, total deflection is limited to L/240, where L is the span length.
    2. Beams – Live load deflection is limited to L/360, total deflection is limited to L/240, where L is the span length.
  6. If a beam is provided as an intermediate stringer support (Mid-Beam) then its span selected should be multiplied by 0.60 for a dropped beam and 0.70 for a flush beam.
  7. Required wind pressure shall be verified by others.

General Notes

  1. This system has been designed and shall be fabricated in accordance with the definitions and requirements of the 2015 International Residential Code and International Building Code including considerations pertaining to the use of Naturally Durable Wood.
  2. This calculator has been developed specifically to address the technical performance of Iron Woods brand products only and should not be relied on for products which cannot be verified as carrying the Iron Woods™ brand through confirming documentation.
  3. Engineering Express is not certifying any wood species parameters without applicable testing proof. The minimum required thresholds are shown below. These thresholds must be verified separately and are by others, and assuming all the parameters can be proven by the manufacturer, only then can we confirm these span charts valid for the intent of the Code.
  4. These are a sample of the species list we used under our analysis, and their required properties (including but not limited to:
    • Iron Woods™ Ipe
    • Iron Woods™ Garapa Gold
    • Iron Woods™ Purpleheart
    • Iron Woods™ Greenheart
    • Iron Woods™ Balau
    • Iron Woods™ Massaranduba
    • Iron Woods™ Angelim Vermello
    • Iron Woods™ Angelim Pedra
    • Iron Woods™ Cumaru
    • Iron Woods™ Ekki

IN ALL CONDITIONS IT IS THE RESPONSIBILITY OF THE PERMIT HOLDER TO ENSURE THE HOST STRUCTURE CAN WITHSTAND THE RATED FORCES BY A COMPLETE SITE-SPECIFIC DESIGN BY OTHERS.

THIS CALCULATOR IS NOT TO BE CONSIDERED A DESIGN APPROVAL AND IS INTENDED AS A STRUCTURAL DESIGN AID TO OTHERS ONLY, FOR IRONWOODS SPECIES. WOOD FIRE RATING, DURABILITY RATING, AND WOOD GRADE SHALL BE VERIFIED AND CERTIFIED BY OTHERS TO MEET APPLICABLE CODE STANDARDS.

NO WARRANTY OF ANY KIND, EXPRESSED OR IMPLIED, IS OFFERED BY THIS ENGINEER AS TO THE INTEGRITY OF THE HOST STRUCTURE TO CARRY DESIGN FORCE LOADS INCURRED BY THIS SYSTEM.

Leave a Reply