AI Prompt - Getting Strategy Recommendations
You can use AI tools to help recommend and evaluate various structural grid placement options.
Recommend grid locations for a rectangular system of structural grids for the building in this image.
- The structural framing will be steel.
- Grid lines should be inset 1' from the exterior wall faces.
- Provide two grid placement strategies and explain the pros and cons of each choice.
Recommendations
Both strategies use the same perimeter grid lines, inset 1'-0" from each exterior face. They differ in how the interior is divided: Strategy A uses about 30' bays with grid lines at the courtyard, and Strategy B uses 50' bays across the west wing with fewer columns.
How I read the plan
- Footprint: an L-shape, 160'-0" east–west. The west wing is 100'-0" wide and 80'-0" deep. The east block is 60'-0" wide and runs the full 110'-8" depth.
- Courtyard: 30' × 30', starting 25'-0" south of the north face. Its west edge lines up with the east block's west wall (100'-0" from the west face). Its east edge is 30'-0" from the east face.
- Coordinates and labels: I measure east from the west exterior face and south from the north exterior face. Numbered grids run north–south and are numbered west to east. Lettered grids run east–west and are lettered north to south.
Perimeter grids (both strategies)
Edge | Exterior face | Grid at |
West | 0' | 1'-0" |
East | 160'-0" | 159'-0" |
North | 0' | 1'-0" |
West wing, south face | 80'-0" | 79'-0" |
East block, south face | 110'-8" | 109'-8" |
East block, west face | 100'-0" | 101'-0" |
Strategy A: about 30' bays, with grid lines at the courtyard
Grid | 1 | 2 | 3 | 4 | 5 | 6 |
Location | 1'-0" | 34'-4" | 67'-8" | 101'-0" | 131'-0" | 159'-0" |
Bay to next grid | 33'-4" | 33'-4" | 33'-4" | 30'-0" | 28'-0" |
Grid | A | B | C | D | E |
Location | 1'-0" | 24'-0" | 56'-0" | 79'-0" | 109'-8" |
Bay to next grid | 23'-0" | 32'-0" | 23'-0" | 30'-8" |
That's about 27 columns per floor. Grids B, C and 5 sit 1'-0" outside the courtyard's north, south and east faces.
Pros:
- Edges framed simply: every exterior face, including three sides of the courtyard, has a grid line. That makes edge beams, slab edges and storefront attachment straightforward.
- Supported courtyard: columns sit just beyond each courtyard corner, so the courtyard is framed by ordinary beams on all sides.
- Economical steel: 23'–33' bays suit composite deck. Expect roughly W16–W21 filler beams and W21–W24 girders, with shallow floor framing and modest column loads.
Cons:
- More columns: more footings and more pieces to erect.
- Columns in the west wing: grids B and C exist because of the courtyard. They put two rows of columns across the west wing, where they may get in the way of layouts.
- Uneven bays: bays range from 23' to 33', which means more distinct member sizes and connections.
Strategy B: 50' bays in the west wing
Grid | 1 | 2 | 3 | 4 | 5 |
Location | 1'-0" | 51'-0" | 101'-0" | 131'-0" | 159'-0" |
Bay to next grid | 50'-0" | 50'-0" | 30'-0" | 28'-0" |
The lettered grids A–E stay as in Strategy A. The courtyard still needs B and C, and the east block is the same in both strategies. That's about 23 columns per floor.
Pros:
- Open west wing: 50' clear spans east–west give much more open, flexible floor plates there.
- Fewer columns: fewer columns, footings and erection pieces.
Cons:
- Deeper beams: 50' filler beams run about W24–W27. That adds roughly 6–8" to the structure depth, so you'd need a taller floor-to-floor or accept a lower ceiling.
- Heavier steel: more tonnage per square foot and heavier columns and footings. Floor vibration needs checking at 50' spans.
- Different bay character: the east block keeps the 28'–32' bays, so the two parts of the building won't match.
Things to settle before modeling
- The line between the east block and the courtyard: the east block's west wall and the courtyard's west wall sit on the same line, 100'-0" from the west face, but with the building on opposite sides. A 1'-0" inset gives 101'-0" for the east block and 99'-0" for the courtyard. Two grids 2' apart doesn't work, so both strategies use one grid at 101'-0", because that wall runs the full height down to the foundation. Columns are left out where that line crosses the courtyard. The cost is that the courtyard's west slab edge sits 1' off the grid, so its edge beam needs short outriggers. The alternative is a supplemental grid at 99'-0" for that edge alone.
- Building depth: the dimensions on your plan don't agree. The left side adds up to 110'-0" (80'-0" + 30'-0"), while the right side reads 110'-8". I used 110'-8". If it's actually 110'-0", grid E moves to 109'-0" and the bay above it becomes 30'-0".
I'd choose Strategy A unless the west wing specifically needs open floor plates. It's the more economical steel frame, and its courtyard framing is cleaner. I can place either set of grids in your Revit model, the same way I added the dimensions.
AI Prompt - Placing the Grids
Place grids in my Revit model using Strategy A
Result
The measurements confirm the plan: 160'-0" × 110'-8", so the building depth really is 110'-8". No grid names clash. Placing the grids now.
All 11 grids are placed. I'll check them in the L1 plan. First I'll set the Boolean back to False so an accidental run won't add a second set.
The Strategy A grids are in Project1: 11 grids, 1–6 and A–E. Revit reported all 11 placed, and they show correctly in the L1 plan. Before placing them, the script measured the building from the walls at 160'-0" × 110'-8". That settles the depth question: 110'-8" is right, so grid E sits at 109'-8".
Grid | Distance |
1, 2, 3, 4, 5, 6 | 1'-0", 34'-4", 67'-8", 101'-0", 131'-0", 159'-0" from the west face |
A, B, C, D, E | 1'-0", 24'-0", 56'-0", 79'-0", 109'-8" from the north face |
Each grid runs 15' past the building at both ends.
Grids are model-wide, so they'll appear in L2 and L3 as well.
On the plan:
- Courtyard: grids B, C and 5 sit 1' outside its north, south and east walls. As in the strategy, grid 4 runs through the courtyard 1' inside its west edge, and no columns belong on that stretch.
- Bubbles: they appear only at the south end of the numbered grids and the east end of the lettered grids. If you'd rather have them at the north and west, as on most structural plans, I can switch them.
How I got there: clicking Revit's ribbon buttons didn't work from my side, so I opened Dynamo with the ribbon's keyboard shortcuts instead. The grid script is now in your "Dynamo Sender" graph, with its Boolean set back to False so a stray run won't add a second set. The same code is in place_grids_strategy_a.py.
Next, I can place steel columns at the grid intersections, leaving out any that fall inside the courtyard.
AI Prompt - Placing Structural Columns at Grid Locations
Place steel columns at the grid intersections, leaving out any that fall inside the courtyard.
Result
Before writing it, I checked the geometry. None of the 30 grid intersections actually falls inside the courtyard: the courtyard spans 100'–130' east and 25'–55' south, and the nearest grid lines (4 at 101', 5 at 131', B at 24', C at 56') all sit just outside it. The exclusion still matters for points outside the L-shaped footprint, though, and the script checks for both.
The script parses. Now I'll run it in Dynamo, starting with a preview.
All 27 columns are placed (W Shapes-Column : W10X49). I'll set the Boolean back to False and check the plan.
I placed 27 steel columns, type W Shapes-Column : W10X49, one at every grid intersection inside the building. Each runs from L1 to L2, the top level in this model. They appear as small dots at the grid intersections in the L1 plan.
None of the intersections falls inside the courtyard. Grids 4, 5, B and C all pass just outside its walls, so the columns at B-4, B-5, C-4 and C-5 frame its four corners from the outside. The only three left out were E-1, E-2 and E-3, which fall in open ground south of the west wing.
W10X49 is a placeholder size for layout, not a design. Ask your structural engineer to size the columns, especially B-4, B-5, C-4 and C-5 at the courtyard corners, which will pick up extra load from the beams framing around the opening.
The script is in place_columns_at_grids.py and in your Dynamo Sender graph, with the Boolean set back to False. If you add levels later and run it again, it skips any intersection that already has a column.
AI Prompts
Placing Structural Grids
Prompt | Tool Options
🟢 = Autodesk Asst
🔵 = Revit MCP
🟣 = Python + Dynamo |
Place grids in my Revit model using Strategy A
Note: This is a follow up to asking for recommendation from the AI tool for placing structural grids based on an image of the building footprint. | 🟣 |
Place grids in my Revit model using this image as a guide | 🟣 |