How to calculate square footage from a plan
Square footage drives flooring, drywall, paint, and roofing bids. Here is how to calculate it accurately from a PDF plan, deduct what does not count, and total it by room or type.
Calculate square footage, step by step
- Set the scale. Calibrate the sheet so measurements read in real feet. See how to set the scale on a PDF.
- Trace each space. Use the area tool to trace the boundary of a room or space, and read the square footage as you close the shape.
- Deduct openings. Cut out openings, shafts, or anything you do not want in the number, so the square footage is net rather than gross.
- Total by room or type. Keep each room or finish on its own group, so the square footage totals the way you bid.
- Speed it up. Run Detect Spaces to outline and name every room automatically, giving you per-room areas in seconds to review.
Tips for accurate square footage
- Confirm the scale against a known dimension before you measure a single space.
- Trace to the right face of the wall, and be consistent across rooms.
- Deduct as you go so gross and net do not get mixed up later.
- Group by finish or room type so totals land ready for pricing.
Square footage by trade
Different trades use square footage differently. See how it works for flooring, drywall, and painting, or measure any plan with free takeoff in your browser, free while TRACEBUILD Lite is in early access.
Common questions
How do I calculate square footage on a PDF plan?
Set the scale first, then use the area tool to trace the boundary of each space. The software reads the enclosed square footage to scale, and you can deduct openings so the area is net.
Do I need to set the scale?
Yes. Square footage is a measurement, so it depends on the drawing's scale. Calibrate the sheet from a known dimension, or pick a standard scale, before you measure.
Can it total the rooms automatically?
Detect Spaces outlines and names rooms from the drawing's own text, giving you per-room square footage in seconds, which you can group and total by type.