A preliminary floor framing plan can be drafted in eight steps: set the footprint; compare joist directions; choose a working spacing; mark support assumptions; add floor openings; add any grid; annotate and review; then export. The result is a coordination drawing for project-specific review, not a construction design.

If the terms here are unfamiliar, start with framing plan symbols explained. For the complete reference, see the floor framing plan guide.

1. Shape the footprint

Start with the outline of the floor. Begin from a rectangle, preset shape, or template, then set the overall width and depth and edit the vertices to match the available background. For an existing building, a traced or measured outline is only as reliable as the survey information behind it; record any unverified dimensions.

2. Set the joist span direction

Compare the possible directions. Running along the shorter clear span often reduces member demand, so the app uses the shorter axis of the bay's bounding box as its automatic suggestion. That is a geometry heuristic, not structural design. Check it against actual support, floor openings, services, cantilevers, depth limits, and the intended joist product; override it when those constraints point elsewhere.

For a code-level explanation of the generator, including polygon clipping and its limitations, see how Framing Plan generates a preliminary joist layout.

3. Set the on-center spacing

Choose a working on-center spacing, the center-to-center distance between joists. The standard US values are 12, 16, 19.2, and 24 inches on center, and 16" o.c. is the common default. For otherwise identical members and loading, closer spacing distributes load among more joists. In the current app, span status compares clear geometry with a bundled sample table. Those sample values are explicitly fabricated for development and demos, not derived from a building code, so the status is not an engineering or compliance check.

4. Mark the load-bearing walls

Mark the walls or beams assumed to support each joist field. In Framing Plan, red wall highlights initially follow the chosen span direction. They make the layout assumption visible, but they do not inspect the real building or prove wall, foundation, or support capacity. Override them to match the available project information and flag anything unknown. Read bearing walls on a framing plan before treating direction as evidence.

5. Add openings and header beams

Place floor openings such as stairwells, shafts, hatches, and material penetrations. They interrupt the joist field, so show the intended header and trimmer joist zone and flag the final member and connection design for review. Doors and windows are wall openings: add them separately when useful for coordination, and do not confuse their wall headers with framing around a hole through the floor. Export keeps opening geometry on its own CAD layer.

6. Add the structural grid and columns

For larger or multi-bay layouts, turn on the structural grid to create shared layout references. A column may align with a grid intersection, but an intersection is not automatically a column location. On a small plan with clear dimensions, a formal grid may add no value.

7. Place symbols and dimension the plan

Add dimensions, member references, and annotations for the distances and assumptions that matter: overall sizes, bay widths, opening offsets, support assumptions, and unresolved items. Confirm the level, units, revision, and preliminary status. Do a final coordination pass against the current architectural background before exporting.

8. Export the drawing

Finally, export. Choose the format for the job:

  • PDF or PNG: clean, presentation-ready drawings with a title block, ideal for review and sharing.
  • DXF: CAD-ready geometry on named layers (Walls, Bearing, Joists, Beams, Grid, Columns, Openings, Elements), in millimeters, for continuing in CAD.

If you plan to hand the drawing to a CAD user or engineer, the DXF route preserves the layer structure they expect.

What happens next

A preliminary plan is a starting point, not a finished structural document. The next step is the project-specific structural review required locally: verify design criteria, loads, member products and capacities, deflection and vibration, openings, bearing, connections, support below, and code requirements. Resolve review comments on every affected level before issuing new drawings.

Ready to try it? Open the framing studio and work through these eight steps on your own footprint. It runs entirely in your browser, and your work autosaves as you go.