Manually Modifying Deck Framing

Reference Number: KB-01245
Last Modified: July 15, 2021

The information in this article applies to:



I need to manually modify deck framing that Chief Architect created in my plan. What are my options?

BBQ, patio, and a deck with stairs going down to the backyard.


When a room is defined as a Deck in Chief Architect, framing is generated automatically. This is a fast way to generate posts, beams, joists and planking, but sometimes manual modifications may still need to be made.

In this article, we will replace a beam, modify posts and footings, as well trim joists and planking to better suit the house plan used in this example. You can then use the techniques learned in this article and apply them to your designs going forward.

Note: Chief Architect is not an engineering program and will not calculate loads or other important structural considerations. Always have your designs approved by a licensed engineer before building.

To create the basic house plan

  1. Select File> New Plan to open a new, blank plan.

  2. Select Build> Wall> Straight Exterior Wall , then draw exterior walls forming a perimeter, making sure to create a fully enclosed space.

    In this example, a structure measuring 30' x 45' is created with a bumpout.

  3. Select Terrain> Create Terrain Perimeter to create a flat terrain pad.

  4. Next, navigate to Terrain> Terrain Specification from the menu.

  5. On the General panel of the Terrain Specification dialog that displays, remove the check from the Automatic box beside Subfloor Height Above Terrain, change the Subfloor Height Above Terrain value to 108", then click OK.

  6. Select Build> Floor > Build Foundation to open the Build Foundation dialog.

  7. On the Foundation panel, select Walls with Footings as the Foundation Type, specify the Minimum Height under the Stem Wall section, then click OK.

    In this example, 101 1/2" is specified as the Minimum Height.

    For information on creating a walkout basement in sloping terrain, please see the Related Articles section below.

To disable automatic deck framing

By default, the program will generate framing when a new Deck room is created or modified. Once the Deck room is defined and the framing built, the room's automatic deck framing needs to be turned off so that it can be modifiedwithout being rebuilt.

  1. Go Up One Floor to Floor 1, select Build> Railing and Deck> Straight Deck Railing and draw railings to enclose one or more Deck rooms attached to the main house. 

    Drawn deck room

    Note: If a Deck is drawn on Floor 1 and a foundation is present, the deck framing will be drawn on Floor 0. If no Floor 0 is present, the deck framing will be created on Floor 1.

  2. Using the Select Objects tool, click in an empty space in the Deck room to select it, then click the Open Object edit button.

    Selected deck room

  3. On the Deck panel of the Room Specification dialog that opens, uncheck Automatically regenerate deck framing, then click OK.

    Turning off the regeneration of deck framing for the room

    Note: Grayed out options on this panel indicate that the Room Type is set to something other than a Deck. For framing to generate, define the room as a Deck, click OK, then open the room back up to specification to disable the setting mentioned in this step. 

To replace a beam

  1. Go Down One Floor to Floor 0.

  2. In order to edit deck framing, we must be able to see it. Use the Active Layer Set Control drop-down to switch to the Framing Layer Set.

    Using the framing view set

  3. Using the Select Objects tool, click on the beam that runs under the Deck room that has Automatic Deck Framing turned off.

    Selecting a beam of the deck

  4. This beam is placed under the deck joists and will interfere with the walkout basement. With the beam selected, click the Delete edit button or press the Delete key on your keyboard.

    Deleted deck beam

  5. We can now modify the deck's rim joist to replace the deleted beam. Select this framing member and click the Open Object edit button.

    Selecting the deck rim joist

  6. On the General panel of the Framing Specification dialog that opens:

    Modifying the deck rim joist

    • Change the Depth to your liking. 

      In this example, a depth of 15 1/2" is specified.

    • Change the Width to your liking.

      In this example, a width of 5 1/2" is specified.

    • Change the Type to "Glulam".

    • Click OK to close the dialog and apply your changes.

    • The new beam is resized concentrically from the centerline outward, so it will have to be moved to compensate for this change.

  7. To do this, click the Transform/Replicate Object edit button while the beam is still selected.

  8. In the Transform/Replicate Object dialog:

    Moving deck rim joist

    • Check the box beside Move.

    • In the Y Delta text field, type 2".

    • Click OK to close the dialog and move the beam.

      New location for deck rim joist

To edit posts and footings

Some of the posts and footings block the view from the walk-out basement windows. The problem posts can be removed and those remaining can be moved and resized to bear the load above.

  1. Using the Select Objects tool, click on one of the posts to select it.

    • Hold down the Shift key on your keyboard and click on another post to add it to the selection set.

    • Continue holding down the Shift key and selecting as many additional posts as you wish.

  2. With the posts selected as a group, click the Delete button or the Delete key on your keyboard.

    Removing unnecessary deck framing

  3. Repeat step 1 and 2 for any footings that need to be removed.

  4. Shift-select the remaining posts under the new beam and select the Open Object edit button.

  5. On the General panel of the Framing Specification (Deck Post) dialog:

    Adjusting deck post to be at the correct height and size

    • Lock the Bottom Height.

    • Specify the Top Height as -8", which in this example is the Bottom Height of the beam noted above.

    • Specify both of the Post Width values as 5 1/2".

    • Click OK to close the dialog and apply your changes.

      Note: You may have to recenter the resized posts on to their footings.

  6. The resized posts and their footings now need to be moved so they are positioned under the Glulam beam. The Transform/Replicate Object edit tool can be used for this purpose:

    • Select Build> Framing> Post from the menu and then hold down the Shift key on your keyboard and draw a rectangular selection marquee around the resized posts.

    • With the posts selected, click the Transform/Replicate Object edit button.

    • In the Transform/Replicate Object dialog, check the box beside Move. In this example, a Y Delta value of -15" is used. Enter the desired value and click OK to close the dialog and move the selected objects.

    • Select Build> Slab> Slab from the menu, draw a marquee around the resized slabs' footings and move these items in the same way.

To trim joists

Instead of bearing on the original beam, the joists will now attach to the edited rim joist using joist hangers. At this point, they are still sized to meet the rim joist before it was resized and need to be shortened.

  1. Select the Glulam beam and click the Trim Object(s) edit button.

  2. Click and drag a temporary line, or fence, that runs through the joists where they extend into the beam.

    Trimming the Glulam beams

  3. When you release the mouse button, the ends of the joists will be trimmed back to the inside edge of the beam.

    Glulam beams after trimming

  4. When you are finished, you can select 3D> Create Perspective View> Full Camera to see the results.