Creating a Log Truss

Reference Number: KB-02781
Last Modified: March 31, 2023

The information in this article applies to:



How do I create log trusses in Chief Architect?

Custom log trusses


While the Truss tool does not produce log trusses, you can download a Bonus Catalog titled Log Truss Template that includes a selection of log trusses, ready to be placed in your plans, as well as templates that you can use to create custom truss sizes. This library can be found in the Millwork section of the Chief Architect 3D Library.

This article describes how to use these templates to create a custom log truss with a 22' span and 12/12 pitch.


To create a custom truss envelope

  1. Create a New Plan , then select View> Library Browser  if your Library Browser is not already open.

  2. Browse to Chief Architect Bonus Catalogs> Log Truss Components> Log Truss Templates and select the 24' - 12/12 Log Truss Envelope.

  3. Click once in the drawing area to place this CAD block at that location.

    24' Log Truss Template

  4. Using the Select Objects tool, click on the CAD block to select it and click the Explode CAD Block  edit button.

  5. For each of the three lines on the right side of the CAD block, click to select the line and then click the Disconnect Selected Edge edit button.

  6. Group select the three lines on the right side CAD block: the lines that represent the end of the bottom log, the top edge of the bottom log, and the top of the right-hand angled log.

    Group select the three lines on the right that have been disconnected

    Note: To learn more about group selecting objects in Chief Architect, please see the Related Articles section below.

  7. With these three lines selected as a group, click the Transform/Replicate Object  edit button.

  8. In the Transform/Replicate Object dialog that displays:

    Moving CAD lines using the Transform / Replicate Object dialog

    • Check the box beside Move.
    • Specify the X Delta as -24" and ensure that Relative To Itself is selected.

    • Click OK to close the dialog and move the selected objects 24" to the left.

  9. Using their edit handles, reconnect the lines of the envelope. Make sure that the top edges meet at the new ridge point and the bottom edge snaps to the log end line on the right.

    Reconnect the CAD lines to form the smaller truss

    • When this is accomplished, the lines will form a closed polyline that, when selected, will have a grey fill color.

    • At this point, the envelope polyline can be used as a guide to customize a truss template.

To modify a log truss template

  1. In the Library Browser, under Chief Architect Bonus Catalogs> Log Truss Components> Log Truss Templates:

    Log Truss Template placed in the plan 

    • Select the 24' - 12/12 Log Truss Template.
    • Click once to place this architectural block in your plan, near the envelope polyline.

  2. Using the Select Objects  tool, click on the newly placed truss template to select it.

  3. Use the Point to Point Move  edit button to align the left side of the truss template with the left side of the envelope polyline.

    Moving the Truss Template to be aligned with the Truss Envelope

    • Click the Point to Point Move  edit button.

    • Click once on the lower left corner of the truss template.

    • Click a second time on the lower left corner of the envelope polyline.

  4. With the truss template still selected, click the Explode Architectural Block  edit button.

    The template's components can now be edited so that the logs on the right side align with the envelope polyline like those on the left side already do. 

  5. Select the right top chord log and use the Transform/Replicate Object  edit button to move it 24" to the left (X Delta of -24"), as described in the section above.

  6. Group select the king post and two angled logs and use the the Transform/Replicate Object  edit button to move them 12" to the left (X Delta of -12").

    Truss template after the logs have been moved

  7. Using the edit handles, shorten each of the modified logs so they fit within the envelope polyline.

    Logs adjusted to fit within the envelope

    • Be sure to shorten the angled logs so they do not extend through the top chords.

    • To override movement restrictions, you can hold down the Ctrl or Command key on your keyboard while resizing these objects.

  8. Once the logs are to your liking, group select all six logs and click the Make Architectural Block  edit button to group them back into a single block again.

To convert the template into a symbol

  1. Select the truss template that was just converted to an architectural block, then click the Convert Selected to Symbol  edit button.

  2. In the Convert To Symbol dialog that appears:

    Convert To Symbol dialog

    • Specify the Symbol Name.

    • Select Millwork from the Symbol Category drop-down list.
    • Make sure that Add to Library is checked.

    • Check the box beside Show Advanced Options.

    • Click OK.

  3. On the 3D panel of the Symbol or Millwork Specification dialog that opens next:

    Rotate the truss along the X axis

    • Select the X Axis radio button under the Rotation heading.

    • Click the Rotate + button one time so the truss is oriented upright in the preview pane.

  4. On the 2D Block panel, click Generate Block to generate the Truss's 2D CAD Block.

  5. Click OK to confirm the changes.

  6. Focusing on the User Catalog, right-click on the new truss object that was just added, then select the Open Object option.

  7. Specify the desired elevation for the truss on the General panel, then click OK to close the dialog.

To save your custom envelope and template

  1. Select the truss template that was converted to an architectural block, then select the Add to Library edit button to add it to the User Catalog.

  2. Select the truss template architectural block that is still currently in the plan and move it so it's no longer on top of the envelope.

  3. Select the label or text object below the envelope and click the Open Object  edit button.  

  4. In the Rich Text Specification dialog, change the text to say 22' Log Queen-Truss Envelope, then click OK.

    Custom envelope with a custom label

  5. Group select the envelope and the text object, click the Make CAD Block  edit button, then click the Add to Library  edit button.