I-joist – BuildSoft Support https://support.buildsoft.eu BuildSoft Support Sat, 28 Mar 2026 08:41:12 +0000 en-US hourly 1 https://wordpress.org/?v=6.2.9 How to do timber design https://support.buildsoft.eu/knowledge-base/how-to-do-a-timber-verification/ Mon, 07 Jan 2019 09:57:28 +0000 http://buildsoftsupport.com/?post_type=ht_kb&p=3445 To assess a structure (whether it is sufficiant or not), the following steps must be followed in sequence:

  • Schematising the construction
  • Determining the internal forces and moments (= global analysis)
  • Checking the cross-sections (= design):
    • Strength
    • Stability 
    • Stiffness

In Diamonds

  • In the Load groups dialog , define the correct Service class.
    The Service class is required to determine kmod.
  • Calculate the internal forces (syn. global analysis) F9 or .
    Decide whether global imperfections are necessary or not.
    Check the option to take the creep into account (more info). 
  • Set the buckling lengths.
    Don’t skip this step! Without the correct buckling lengths the stability results have no meaning.
  • Select the correct timber standard using the menu Analysis > Timber standard.
    A list with all available standards in Diamonds can be found here.
  • Click on F3 or to start the verification (more info).
    The verification is supported for:

    • constant cross-sections with shapes: 
    • variable cross-sections with shape: 

    At the moment it is not possible to do a timber verification on H-shaped cross sections or composed cross-sections (Section Utility).

  • To view the results, go to the results configuration .
  • Click on .
    The results of the strength check are behing the button , for those of the stability check click .
    The results of the strength and stability check are displayed as a percentage:

    • A structure is sufficient for strength, if the percentage is less than 100% for all bars.
    • A structure is sufficient for stability, if the percentage is less than 100% for all bars.

    Based on the percentage no judgment can be made on the extent to which a section is sufficient or not. This is because the used formulas are not always linear.

  • Optionally, optimize the cross-sections.
    You can use the Optimization-function for this , but it might take a few iterations (and thus time).
    We recommend that you change the cross-sections manually to one (or more) size(s) bigger/smaller depending on the result you had then recalculating the model. Exspecially for experienced engineer, this works faster than the Optimization function.
  • Don’t forget to verify the stiffness! Thus the vertical and horizontal deformation.
    Diamonds can calculate the relative deformation, but it’s still up to you to verify it.
    A structure is sufficient if the strength, stability and stiffness are sufficient.
]]>