01 / Sketch the outline
Draw the shape before the numbers.
Sketch every wall and any alcove or recess. Mark the entrance so you can orient yourself later. For a rectangle, measure the inside length and width. For an irregular room, measure each wall segment and record what separates the sections.
Do not stretch an L-shaped room into its largest possible rectangle. That rectangle includes space beyond the actual walls. Keep the original shape on your sketch and check which shapes your planning tool supports.
02 / Record what stays
Notice the small projections.
Measure usable wall segments and the depth of fixed cabinets, columns, radiators, and similar obstructions. If skirting or trim projects into the space where the furniture will sit, account for it.
Place each object using an offset from a corner: for example, “window starts 24 inches from the left corner.” Record its width too. A width without a position is hard to place correctly.
03 / Add openings and movement
Leave room for doors to work.
Mark each doorway's position, clear opening width, hinge side, and swing direction. Include cupboard doors and drawers where furniture could stop them opening.
For tall furniture, record ceiling height and any lower beam or sloping ceiling at the intended position. Width and depth alone cannot confirm that a wardrobe fits under a slope.
A room layout checks placement inside the room. Measure the delivery route separately, especially stairs, turns, and elevators. See the couch delivery check.
04 / Keep the units consistent
12 feet 6 inches is 12.5 feet.
Write a unit beside every measurement. When entering a feet-and-inches measurement into a field that accepts decimal feet, convert the inches to a fraction of a foot.
12 ft 6 in = 150 in = 3.81 m
12 × 12 + 6 = 150 inches.
6 ÷ 12 = 0.5 feet, so enter 12.5 feet in a decimal-feet field.
Do not enter 12.6 to mean 12 feet 6 inches. That is 12 feet 7.2 inches, which adds 1.2 inches to the room.
| Feet / inches | Inches | Metres |
|---|---|---|
| 1 ft | 12 in | 0.3048 m |
| 10 ft | 120 in | 3.048 m |
| 12 ft 6 in | 150 in | 3.81 m |
05 / Check the decision-changing dimensions
Measure the tight spots twice.
Label each number as measured, taken from a supplied plan, or estimated. If a sofa appears to fit by a small margin, recheck the wall segment and the sofa's outside dimensions instead of treating the estimate as exact.
Next, add the overall width and depth of each furniture piece you want to keep. Try the arrangement, inspect obstructions, and adjust the layout before deciding what to replace.