Finishes
Room Finish Areas Calculator
Enter the room length, width and ceiling height, then how many doors and windows to subtract. You get floor, ceiling and wall areas and the baseboard length. These are the base numbers for paint, drywall, flooring and trim estimates.
Result
Planning estimate- Floor area
- 168.00 sq ft
- Ceiling area
- 168.00 sq ft
- Gross wall area
- 416.00 sq ft
- Opening deduction
- 44.01 sq ft
- Net wall area
- 371.99 sq ft
- Room perimeter
- 52.00 ft
- Baseboard length (door gaps removed)
- 49.00 ft
Assumes a flat ceiling the same size as the floor.
Perimeter x ceiling height, before any openings.
Baseboard length before door gaps.
Perimeter minus the width of each door.
How it is calculated
- 1 Floor area = length x width. Ceiling area is taken as equal to the floor area.
- 2 Perimeter = 2 x (length + width). Gross wall area = perimeter x ceiling height.
- 3 Opening deduction = doors x door width x door height + windows x window width x window height.
- 4 Net wall area = gross wall area - opening deduction, never less than zero. If you choose not to deduct openings, net wall area equals gross wall area.
- 5 Baseboard length = perimeter - doors x door width, never less than zero.
Assumptions to confirm
- Rectangular room
- The room is a simple rectangle with a flat ceiling. For L-shaped or irregular rooms, split the room into rectangles and add the results.
- Default door size
- The default door is 3 ft wide by 6.67 ft (about 6 ft 8 in) tall. Change it to match your doors. All sizes here are in feet, so enter 6 ft 8 in as 6.67.
- Default window size
- The default window is 3 ft by 4 ft and the default ceiling height is 8 ft. These are placeholders. Measure or take them from your drawings.
- Same size for every opening
- All doors share one size and all windows share one size. If yours differ, run the room more than once or adjust the counts to an equivalent area.
- Baseboard and doors
- Every door is assumed to interrupt the baseboard for its full width, and the deduction applies even if you choose not to deduct openings from wall area. Closet openings, cased openings and built-ins are not handled, so adjust the door count to suit.
This is an early planning estimate, not a quotation. Check quantities against your drawings, your specification and the manufacturer's data.
Questions about this calculator
Should I deduct doors and windows from the wall area?
For paint, most estimators subtract larger openings, but some leave them in as a simple allowance for trim and cutting. For drywall, check how your spec or supplier counts openings. The deduct option lets you compare both.
Why is the ceiling area the same as the floor area?
A flat ceiling covers the same footprint as the floor. Vaulted, sloped or coffered ceilings have more surface, so measure those separately.
Where do I use these numbers next?
The net wall area and ceiling area feed the Paint Quantity Calculator. The floor area and baseboard length are the inputs for flooring and trim.
Take these numbers off the drawings
Estimateria reads the door, hardware and finish schedules out of your PDFs into a priced grid, so the quantities you check here start from the set instead of a retype.