Creating a Building with Curved Walls from a Floor Plan Sketch

I'll build this in Revit: three levels at 12' spacing, the boat-shaped shell with walls, curtain walls, doors, an atrium-cut floor on each level, a curved stair, and a 4' overhanging roof. First I'll check what's open in Revit.

Empty project with L1 and L2. Let me inventory the available types.

Model is empty and has all the types I need. Before touching Revit, I'll work out the plan geometry from the sketch locally and check it.

Plan geometry checks out (240' long, 80' wide at midpoint, stair fits in the east lobby with clearance). Now a quick check of the Revit version and a few remaining types.

Revit 2027 (needs Int64 ElementIds). I'll build in two passes: first levels, the curtain-wall type, exterior shell, entries, and the interior room walls/doors on all three floors.

Levels and the curtain-wall type committed; the wall flip check needs a regenerate first. Let me confirm nothing half-built remains, then rerun with that fixed.

The whole run rolled back cleanly. Rerunning with orientation checked after regeneration.

Shell and rooms are in: 22 exterior wall segments (10 basic, 12 curtain), 90 interior walls and 48 doors across three floors. Now the floors, roof, atrium guardrails and the curved stair.

Something returned null in the roof step. Checking what committed before isolating it.

Walls and doors are intact; the failed run rolled back as a unit. I'll make the roof from the outer footprint and cut the atrium with an opening instead, each step guarded.

Floors (atrium + stair openings at L2/L3), the roof with 4' overhang and open atrium, and glass guardrails are in. Last piece: the curved stair, two spiral flights with a landing at L2.

Stair came out with both flights stacked at L1–L2. I'll edit it: raise the second flight's top to L3 first, then its base to L2.

Stair is correct: 42 risers at 6.86", flights L1→L2 and L2→L3 with a landing at L2. Now a 3D view to check the whole thing visually.

That call timed out on the computer side; it may still have finished. I'll check state with a read-only query rather than rerun it.

The building is built in Revit, but Revit stopped responding during a final cleanup step, so I've paused rather than keep sending commands.

What's in the model (verified before Revit went quiet):

• Levels: L1 at 0', L2 at 12', and new L3 at 24' and Roof at 36', each with a floor plan.
• Exterior shell: two arcs, 240' long by 80' wide, running the full 36' height. There are 10 basic wall segments (EIFS on metal stud) and 12 curtain wall segments. The curtain walls use a new type, "Curtain Wall - Vertical Grid 5'", with vertical grids 5' apart and mullions.
• Entries: three 72"×84" double doors on L1, at the west nose, the north side and the southeast.
• Rooms on all three floors: 7 rooms on the north side and 7 on the south, 18' deep, along a corridor that wraps the atrium. That's 90 interior walls and 48 doors in total: one door per room, plus a vision-lite door at each wing's east end into the lobby.
• Floors: a full slab at L1, which is the atrium floor. L2 and L3 have openings for the atrium and the stair.
• Roof: flat EPDM-on-metal-deck roof at 36', overhanging 4' past the exterior walls, with the atrium left open.
• Atrium: glass-panel guardrails around the atrium edge at L2 and L3.
• Curved stair: in the east lobby, running L1 to L3 as two spiral flights with a landing at L2. It has 42 risers at 6.86" with 11" treads.
• 3D view: "Atrium Building - 3D".

Things to know:

• I built the plan along the X axis rather than at the sketch's diagonal.
• Entry doors are in short solid wall segments, not in the glazing. The model has no curtain-wall door family loaded.
• The roof is open over the atrium. It could take a skylight instead if you'd like.

Still open from the cleanup step:

• Turning off the crop boxes on the architectural plans. The L2 plan currently cuts off the east end.
• Giving the new curtain wall type its own Type Mark.
• Fixing a "stair components not continuously connected" warning at the L2 landing.

That cleanup call may still finish once Revit frees up. Can you check Revit for an open dialog or approval prompt? Once you tell me it's clear, I'll confirm what applied, finish the rest, and save if you'd like.

Revit still isn't answering. Even the basic status check, which runs no code, times out after 10 seconds. That points to the Revit connector being blocked on your computer, not to the model itself.

The most likely cause is the review step: each script I send has to be approved in Revit before it runs. Two of my requests may be waiting in that queue, possibly in a window hidden behind Revit or on another monitor:

• the cleanup (plan crops, Type Mark, stair landing)
• a read-only check of the model

If you find a review prompt, approve both. Running the cleanup twice does no harm.

If there's no prompt anywhere, the connector add-in has probably hung, and restarting it (or Revit) should clear it. Everything from the main build was already committed, so save first if Revit still lets you.

Once Revit responds, I'll re-check the model, finish whatever didn't apply, and save. Or, if you'd like, I can take a screenshot of your screen to look for the blocked prompt myself.

That's what's blocking everything. While Revit is in a placement command, it won't run anything sent from outside, including my status check. I didn't start that light fixture placement; it was probably triggered by a click or shortcut in Revit.

Press Esc twice to cancel it, until the ribbon is back on the Architecture tab with nothing active. Don't place the fixture.

Then let me know. My queued requests should run on their own once Revit is idle. I'll check what applied, finish the cleanup and save.

The cleanup never ran, so the model is as I left it. One lighting fixture also exists that I didn't place. I'll leave it alone and run the cleanup now.

Type Mark and plan crops are fixed. The automatic landing isn't possible for spiral flights, so I'll redraw the sketched landing to match the flights' actual end and start lines.

The cleanup is done and the model has no warnings.

• Stair: the L2 landing now meets both flights exactly, which cleared the "not continuously connected" warning.
• Curtain wall type: it now has its own Type Mark, CW-V5, which cleared the duplicate-mark warning.
• Plan crops: crop boxes are off on all four architectural floor plans, so the whole building shows in Revit. My image export still frames the plan off to one side because of the elevation markers out to the west. That only affects the export, not the view.

Two things need you:

1. Light fixture: a 1x4 - 120 fixture was placed while Revit was in that placement command. I haven't touched it. Should I delete it, or are you keeping it?
2. Saving: I haven't saved, because the model is still the unsaved "Project3". Saving from here would open a Save As dialog and block Revit again, like before. Use Save As yourself; after that I can save it from here whenever you like.

I'll check which structural column, framing and material types the project has, since CLT/glulam families may need to be created.

No timber families are loaded. I'll look for glulam/timber families in the Revit library on your computer.

The Glulam families are loaded. I'll lay out the grid geometry locally first and check it against the atrium and stair openings before placing anything.

No clashes with the atrium or stair openings, and spans top out at about 24'. A quick plot to eyeball the layout:

Entries are clear and nothing hits the openings. Exporting the grid data so I can send it to Revit:

Now the Revit build. The first pass creates the CLT material, CLT floor and roof types, swaps the L2/L3 floors and the roof to CLT, and places glulam columns on every floor.

The floor type rejects a freshly built layer stack. I'll edit its existing compound structure instead (same fix for the roof).

CLT floors and roof are in, plus 177 columns (59 per floor). Now the glulam beams at L2, L3 and Roof, sized by span and set with their tops at the underside of the CLT.

All 291 beams placed with no failures. Two duplicate Type Mark warnings came from the duplicated CLT types; I'll clear those and render a structure-only 3D view.

The timber frame is in and the model has no warnings. I added a "Timber Frame - 3D" view that shows only the structure.

What's in the model:

• Glulam columns: 177 columns, 10¾" × 10½", Western Species. They're stacked per floor at 59 grid points.
• Glulam beams: 291 beams at L2, L3 and Roof, sized by span:

• Beam lines: curved ring beams follow the exterior, the corridor wall and the atrium edge. Straight beams run across the room partitions and over the corridors. A freestanding column in each of the west nose and east lobby carries the longer spans, clear of the stair opening.
• CLT floor plates: the L2 and L3 floors are now "CLT 5-ply 6 7/8"" with the same atrium and stair openings. Beam tops sit at the underside of the CLT, which leaves about 9'-11" clear under the deepest beams.
• CLT roof deck: the roof is now EPDM over 6" insulation over 5-ply CLT, keeping its 4' overhang and the open atrium.
• L1: stays a concrete slab on grade.

Decision for you: the frame is a conceptual layout, not engineered. Sizes come from span rules of thumb, not load calculations. It also has no lateral system yet, such as braced bays or CLT shear walls, and no connections.

Choices I made:

• Perimeter columns sit just inside the exterior wall line.
• Two perimeter columns were shifted so they don't block the west and southeast entry doors.
• Corridor-line columns sit at the room partition junctions.

Saving is still on you: use Save As on "Project3", and after that I can save from here whenever you like.

I'll add grids matching the column layout: arc grids on the six ring lines (perimeter, corridor and atrium edge, north and south), radial grids through each column line, and short grids through the two freestanding lobby columns.

32 grids are in. One column, the east-tip column, isn't registering on a grid, so I'll check why.

The two perimeter arc grids came out slightly off radius (about 0.3–0.8'), so they miss the east-tip column. I'll rebuild those two from the exact center and radius.

The mismatch is up to about 0.9' on the south side, enough to put some perimeter columns into or away from the wall. I'll check whether the existing walls themselves still close at the tips.

The structural grids are in, and all 177 columns sit on a grid line.

Grids added (32):

• Six ring grids following the column rings:
• AN and AS: the perimeter columns, 1'-3" inside the exterior wall line.
• BN and BS: the corridor-wall columns.
• CN and CS: the atrium-edge columns.
• Radial grids N1–N11 and S1–S12: numbered west to east, running from the atrium or corridor line out through each perimeter column, extending 8' past the building.
• Lobby grids W1, E1 and E2: through the two freestanding columns in the west nose and east lobby.

Problem in the building model: setting the grids exposed a bug in my earlier build. Revit's Python rounded the arc centers to whole feet, so the walls I built first sit on slightly different arcs from the frame and grids.

• East tip gap: the north and south exterior walls don't meet at the east tip; there's a gap of about 1'-4".
• Perimeter columns: they sit up to about 0.9' off their intended position relative to the exterior walls, mostly on the south side.
• Corridor walls: the room and corridor walls are similarly offset from the BN/BS column lines.
• Floor and roof edges: these are slightly off the walls too.

The frame, grids, atrium openings, railings and stair are all on the correct geometry.

Proposed fix: delete and rebuild the exterior walls, room walls and their doors on the correct arcs. Then reshape the floor and roof edges to match, using the same types, layout and door positions. That's 112 walls and 51 doors recreated. Any edits you've made to those walls or doors by hand would be lost. Should I go ahead?

Rebuilding now. First pass: delete the walls (their doors go with them) and recreate the exterior shell, entries, room walls and doors on the true arcs.

Floors and roof are rebuilt on the true arcs with their CLT types, and the atrium guardrails were unaffected. A visual check:

The rebuild is done and the model has no warnings. The walls, floors, roof, frame and grids now all sit on the same arcs.

• Exterior shell: the 22 exterior wall segments were rebuilt with the same basic and curtain wall pattern. The north and south walls now meet exactly at the east tip.
• Entry doors: the 3 double doors are back in their original positions.
• Rooms: the 90 room and corridor walls and 48 room doors were rebuilt on all three floors. Every perimeter column is exactly 1'-3" inside the exterior wall line, and the corridor columns sit on the corridor walls.
• Floors: the L1 concrete slab and the L2/L3 CLT plates were recreated with the atrium and stair openings.
• Roof: the CLT roof was recreated with its atrium opening, and the 4' overhang is now uniform all the way around.
• Unchanged: the glulam frame, the 32 grids, the atrium guardrails and the stair weren't touched, since they were already on the correct geometry.

The L2 plan now shows the grid bubbles around the building, and the 3D view shows the timber frame behind the glazing.

Saving is still on you: use Save As on "Project3", and after that I can save from here whenever you like.

Revit issued a few warnings about creating duct connections in the wrong direction. These required deleting the elements the automation tried to place.

I'll check what HVAC content the project has: round duct types, supply system types, air terminal and air handler families.

Sliding along the trunk line moves the riser toward the atrium edge. Instead I'll pull the south riser back toward the corridor wall, between the two ring beams.

A south riser offset of 20'-7" from the exterior wall line clears everything. Next I'll pick each rooftop unit's orientation so its footprint sits on the roof deck clear of the atrium opening.

The south unit clears the atrium opening by just over 2'. Exporting the duct layout so I can send it to Revit:

Placement pass: fix the three corridor beams, place the 42 diffusers (face at 8'), set both rooftop units on the roof, and cut riser shafts through the floors and roof.

That call timed out on the computer side. It isn't safe to repeat, since it would duplicate the diffusers, so I'll check what landed first.

The flip worked (all 42 necks now face up), but the move didn't take, because the diffusers are hosted on their work planes. I'll set the offset from host instead.

The offset isn't taking effect either. Moving the three diffuser reference planes up ½" will carry the hosted diffusers with them.

Diffuser faces now sit exactly at 8'-0" on every floor. Next I'll build the L1 ductwork as a test: the 18" trunks, 7 taps per side and the 12" branches. If that's clean, I'll repeat it on L2 and L3.

L1 built cleanly: both trunks, all elbows, and 14 branches with taps. I'll quickly confirm every L1 diffuser is actually connected, then build L2 and L3 the same way.

Both systems exist with 21 diffusers each, but Revit still sees a break in the physical network. I'll find any unconnected duct or fitting ends.

L1 works: each drop is a 12" elbow plus a short straight piece into the diffuser neck, and all 14 diffusers are connected. Same for L2 and L3:

All 42 diffusers are connected. Last pieces: cap the six trunk dead ends, rebuild the two supply systems, and confirm there are no open connections.

Each diffuser is correctly at 225 cfm, so the system-level figure may be measuring something else. I'll check the flow Revit computes in the ducts at each rooftop unit.

All 42 diffuser connectors read 225 cfm "In", so the terminals are right and the issue is in the roll-up. I'll check the system type's calculation setting.

The cap utility only works on pipes. I'll place Round Endcap fittings directly instead: orient each to face its trunk, size it to 18", then connect it.

Capping fixed the flows. Each system now carries 4,725 cfm, building up 225 cfm per office toward each riser. One detail: the caps came in at 12" instead of 18". I'll size them to match the trunks.

Caps are now 18". A quick HVAC-only 3D view to check it visually:

The supply-air HVAC system is in. Both systems are continuous from rooftop unit to diffuser, with no open ends and no warnings. I added a "Supply Air HVAC - 3D" view that shows only the ductwork over transparent floors.

What's in the model:

• Diffusers: 42 supply diffusers, one per office on each floor. Each is 24×24 with a 12" round neck, face at 8'-0" above the floor, set to 225 cfm.
• Branches: each office has a 12" branch using the "Taps / Short Radius" duct type. It takes off the trunk with a round tap, runs at 9'-4", and drops into the diffuser through an elbow.
• Trunks: 18" round trunks using the "Taps" type run along the corridor on each side of the atrium on all three floors. They're capped at the west end.
• Risers: one 18" round riser per side using the "Tees" type. Each starts with an elbow at the L1 trunk, takes tees at L2 and L3, and connects to its rooftop unit through a round-to-rectangular transition. Shaft openings cut through L2, L3 and the roof.
• Rooftop units: RTU-N and RTU-S, 12.5-ton packaged units with bottom supply, set on the roof deck clear of the atrium opening.
• Systems: "SA-N (RTU-N)" and "SA-S (RTU-S)" each serve 21 diffusers at 4,725 cfm. Revit's flow roll-up checks out: 225 cfm accumulates per office along each trunk, and 1,575 cfm per floor feeds each riser.

Frame changes to make room for the ducts:

• Corridor-line ring beams: all 42 (one per bay, per floor) are now 10¾"×18" instead of 21". This let the 12" branches cross underneath with enough height for the elbow drop. At 22' spans that's on the shallow side for glulam, so it's worth flagging to your structural engineer.
• One corridor beam line: the 24" beam on that line was also reduced, on all three floors.

Decisions for you:

• Riser and trunk velocity is high. The specified 18" size carries the full 4,725 cfm only in the riser above L3, which works out to about 2,700 fpm. The trunk segments nearest each riser run around 900 fpm. Upsizing the risers to 22–24" would bring them into a typical low-pressure range.
• This is supply only. There's no return or outside-air path yet; the rooftop units have return connections ready.
• Ducts pass through the corridor walls without cut openings.

Saving is still on you: use Save As on "Project3", and after that I can save from here whenever you like.