PreConstruct AITo do a drywall takeoff from a PDF, check the scale on each sheet, read the partition schedule, measure the walls on the floor plans as lengths by wall type, take each type's height from the schedule, sections and ceiling plan, take out the openings, add the ceilings, then turn the lengths and areas into sheets, studs, track, screws, tape and compound. The steps are the same in any takeoff software or a PDF viewer that measures to scale.
The steps
- Get the whole set, and the addenda. Architectural plans, reflected ceiling plans, sections, the partition schedule, the door and window schedules, and the Division 09 specification. Check the bid documents for addenda before you measure: see how to read an addendum before you bid.
- Check the scale on every sheet. Read the scale in the title block or under each drawing, then measure a printed dimension (a grid line or a room) and see that it agrees. A PDF printed to fit a smaller page, or a detail at a different scale on the same sheet, is where a takeoff goes wrong without anyone noticing.
- Read the partition schedule. Each wall type gives the stud size and spacing, the board type, thickness and layers on each face, the insulation, the height (to the ceiling plus an extension, or to the deck) and any rating. Write each type down once. The legend line by line: how to read a drywall partition schedule.
- Measure the walls by type. On the floor plans, trace each run of partition and keep one running length for each wall type. Note the walls that are board on one face only (shafts, furring, the exterior walls you line).
- Set each type's height. The schedule says to the ceiling or to the deck; the reflected ceiling plan gives the ceiling height and the sections give the deck. A type that runs to the deck under two different ceilings is two heights.
- Take out the openings. Doors and windows come from their schedules. Choose one rule for what you deduct and keep it for the whole job; the choice is set out under Division 9 takeoff.
- Add the ceilings and bulkheads. From the reflected ceiling plan, the area of each gypsum ceiling type, and the bulkheads and soffits as lengths with their girth.
- Turn it into material. Board area is
length × height × faces × layers, less the openings. Studs are the length divided by the spacing, plus one, plus your extras at openings, corners and ends. Track is the length twice, top and bottom. Screws, tape and compound follow from the board area. - Add waste once, and round up once. Add your waste allowance to the board area, then divide by the sheet size. Add the walls of a type together before rounding, so each wall is not rounded up on its own.
- Check what goes missing. Backing, headers, control joints, deflection track, clouds and the rest: the drywall takeoff checklist.
A worked wall, in imperial and metric
A corridor partition 60 ft (18.29 m) long and 10 ft (3.05 m) high: 3⅝ in steel studs at 16 in centres, one layer of ⅝ in board on each face, two doors 3 ft × 7 ft. Hung with 4 × 10 sheets (40 SF, 3.72 m²), 10 per cent waste.
| Material | Working | Quantity |
|---|---|---|
| Wall faces | 60 × 10 × 2 faces | 1,200 SF |
| Doors | 3 × 7 × 2 doors × 2 faces | 84 SF |
| Board, net | 1,200 − 84 | 1,116 SF (103.7 m²) |
| Board, with waste | 1,116 × 1.10 = 1,227.6 SF ÷ 40 | 30.7 → 31 sheets of 4 × 10 |
| Studs | 60 ft × 12 ÷ 16 = 45, + 1, + 2 at each door | 50 studs, 10 ft |
| Track | 60 × 2, top and bottom | 120 LF, 12 lengths of 10 ft |
| Screws | about 1 a square foot of board on walls at 16 in centres; 31 sheets × 40 | about 1,240 |
| Tape | 1,116 × 0.37 (about 370 ft per 1,000 SF) | 413 LF (126 m) |
| Compound, all-purpose | 1,116 × 0.01 (about 10 US gal per 1,000 SF) | 11.2 US gal (42 L) |
The extras at the doors, the waste and the finishing rates are this example's; yours come from your crews and the specification. The same wall in square metres, with the metric rates, is in drywall per square metre.
Quick answers
Can I do a drywall takeoff with a free PDF viewer?
Yes, if it measures at a calibrated scale. You measure the lengths and areas in the viewer and do the material arithmetic yourself: the free drywall calculator and the takeoff spreadsheet do that part.
Can AI do a drywall takeoff?
Software can read the text on a set (the scales, the partition schedule, the other schedules) and suggest walls, but no tool finds every wall, so the estimator checks each one. How to test any takeoff tool on a job you have already bid.
Do I measure walls at the centre line or the face?
Pick one and keep it for the job. On a typical partition the difference is the wall's thickness at each end, small against the run; it matters on short walls and at many corners, so a set full of small rooms is worth measuring to the face.
Doing it on the drawings
In PreConstruct AI the scales are read off the title blocks for you to confirm, the wall types come from the partition schedule, and walls are suggested on the plans as a beta: you check each one or draw it. Each wall type then buys its board, studs, track and finishing at your waste and rates, in imperial, metric or both, with the sheet and the arithmetic beside every number. The whole job on our sample set: commercial drywall material takeoff.