Modifying exterior walls and your plan outline
The Shape Editor turns a plain rectangle into any outline: split walls into segments, pull out bays, add whole extensions, remove walls, restyle them as railings or glass, and dial in exact dimensions.
Every floor plan starts as a simple shape — but almost no home stays one. The Floor Plan Shape Editor is where the outline itself becomes editable: open it from Edit Floor Plan Shape in the Build panel, and the editor takes over the screen with your plan on a ruler grid, live corner/area/perimeter stats at the bottom, and five tools along the footer.
Everything in this editor is provisional until you press Update Floor Plan — and undo/redo covers every move, so experiment freely.
What you'll need
- •A floor plan open in the editor — any starting shape works
Step by step
- 1
Get the view comfortable
Zoom and pan first so the wall you're working on has room around it — you'll be dropping corners just outside the outline, so give yourself margin.
- 2
Split Walls — sculpt the outline
With Split Walls active, tap any wall to drop a new corner on it. Drop one about a third of the way in and another near the far end, then drag the middle segment outward — that's a bay outline in three moves. Every new segment shows its exact length as you drag, you can move corners or whole segments, and a corner you don't need can simply be removed.
- 3
Add Walls — extend the plan
Switch to Add Walls, tap an existing corner to start a new run, then click corners outside the current outline and close the loop back onto the plan. RoomSketch3D automatically converts the old exterior wall — now inside the enlarged plan — into an interior wall: keep it as a room divider (add a door or windows to it in the design editor), or delete it there for one open space.
- 4
Remove Walls — and restore them
Switch to Remove Walls and tap a wall: it turns into a dashed outline, meaning removed but remembered. Tap the dashed wall again to restore it — nothing is lost until you update the plan.
- 5
Edit Wall Style — walls, railings, glass
Edit Wall Style lets any segment be something other than a solid wall. Choose Wall or Railing, and under Railing pick a style: Spindle, Pony Wall, Glass, or — under More — Horizontal Slat, Cable, Wrought Iron, and Picket. Think gallery landings, indoor balconies over a living room, a pony wall for the bathroom, or glass along a stairwell.
- 6
Edit Wall Length/Thickness/Height
For exact numbers, use Edit Wall Length/Thickness/Height: select a wall and type its length (say, 3 ft to 5 ft), then set thickness and height the same way — that's how a segment becomes a true half wall.
- 7
Update Floor Plan
Press Update Floor Plan to commit. The new outline lands in the design editor, and one tap into 3D shows the bay, the extension, and every railing exactly as drawn.
Tips
The dashed wall is a feature
Removed walls stay as dashed outlines until you update — so you can try an open corner, look at the stats, and tap the wall to bring it right back.
Watch the footer stats
Corners, area, and perimeter update live as you reshape — handy when you're extending a plan toward a target square footage.
Angles on demand
Toggle Angles to see the angle at every corner — the quickest way to keep an extension square (or deliberately not).
Common mistakes
Rebuilding the plan instead of splitting it
You never need to start over to get an L-shape or a bay — split the wall you have and pull. The editor exists precisely so the outline stays editable after day one.
Deleting the converted interior wall too early
After an extension, the old exterior wall becomes an interior wall. Before deleting it, consider whether it's actually your new room divider — often a door in that wall is the better floor plan.
Frequently asked questions
Does reshaping the outline delete my furniture?
No — furniture stays where it is. Pieces that end up outside the new outline or in a wall's path will show up in Smart Flow Check so you can move them.
What's the difference between this and the Bay Window tool?
The Bay Window tool places a window fixture with a projected sill. Splitting walls in the Shape Editor changes the actual floor outline — use it when the bay is real floor area, not just a window.
Can I use meters instead of feet?
Yes — the editor has its own ft / m toggle in the top-right corner, independent of where you are.
What happens to wall styles in 3D?
They render exactly as chosen — spindles, glass panels, pony walls, cable, wrought iron — so an indoor balcony railing looks like one the moment you open the 3D view.
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