What Is a Floor Plan?
A floor plan is a top-down (bird's eye) view of a room or home, drawn to scale. It shows the positions of walls, doors, windows, and furniture — essentially a map of the space. In interior design, floor plans are used to plan furniture placement, circulation paths, and the spatial relationships between elements before anything is physically moved or built.
Common Floor Plan Symbols Explained
Walls
Walls are shown as thick solid lines. In CAD drawings, walls may have two parallel lines with a fill pattern between them. The thickness of the line roughly corresponds to the thickness of the wall — exterior walls are thicker than interior partition walls.
Doors
A door is shown as a thin line (the door itself) and a quarter-circle arc showing the door's swing path. This arc is critical — it shows you how much clearance the door needs when it opens. Make sure no furniture sits within this arc. Sliding doors are shown as two parallel lines with an arrow indicating direction.
Windows
Windows appear as three parallel lines crossing a wall — two thin lines for the frame and one in the middle for the glass pane. Bay windows show as projected rectangular forms extending slightly beyond the wall line.
Furniture
Furniture is represented as scaled shapes at the same size as the actual piece. A sofa at 1:50 scale will look small on paper — always mentally scale up. Kitchen counters appear as L, U, or parallel rectangles along walls.
Understanding Scale
Scale is the ratio between the drawing and reality. 1:50 means every 1cm on paper equals 50cm in reality. So a room that is 4 metres wide (400cm) will appear 8cm wide on a 1:50 drawing. A scale rule (available at any stationery store) makes checking dimensions easy — or use the scale bar printed on the drawing.
Common scales used in residential interior drawings:
- 1:50 — standard for room plans, allows good furniture detail
- 1:100 — used for whole-home overview plans
- 1:20 — detail drawings for kitchen and wardrobe elevations
How to Check Dimensions
Dimensioned floor plans have measurement annotations printed on them. Always check these key dimensions:
- Room size: Does it match your physical measurements?
- Furniture clearances: Is there at least 75–90cm between facing furniture pieces? 90cm minimum for walkways
- Door clearance: Nothing should sit within the door's swing arc
- Kitchen aisle width: 90cm minimum for a single cook, 120cm for two people working simultaneously
- Bed placement: Is there at least 60cm on each side of a double bed for movement?
Circulation Paths — The Most Overlooked Element
Walk through the plan mentally. Imagine entering the front door — where do you go first? How do you move from the kitchen to the dining table? From the bedroom to the bathroom at night? These mental walkthroughs reveal circulation problems that photographs of finished rooms never show.
Spotting Problems Before Execution
Common problems visible in floor plans that clients miss:
- Wardrobes that block windows when opened
- Dining tables too close to walls — chairs can't be pulled out properly
- Kitchen work triangle distances too large (walking more than 3m between sink, stove, and fridge is inefficient)
- TV positioned to catch window glare
- Bed facing the bathroom door directly
These are all fixable on paper for zero cost. After execution, they cost time and money to correct. Always review the floor plan thoroughly with your interior designer before approving. Also read our guide on how to plan interior design from scratch for the full picture.
Frequently Asked Questions
1:50 scale means every 1cm on the drawing equals 50cm in reality. A 4-metre room would appear 8cm wide on a 1:50 drawing.
A kitchen aisle should be at least 90cm wide for one person working and 120cm for two people working simultaneously.
Door swing arcs show the quarter-circle path a hinged door sweeps through when opening. No furniture should be placed within this arc, or the door cannot open fully.
Problems visible in a floor plan — wrong furniture clearances, circulation blocks, poor window placement — cost zero to fix on paper but significant time and money to fix after execution.