What is a takeoff in construction?
A takeoff is the process of measuring and counting everything shown on the drawings (linear feet, square feet, cubic yards, and each item) so it can be priced in an estimate. It is the same as a quantity takeoff. The takeoff produces quantities only; the estimate adds prices, labor, equipment, overhead, and profit to reach a bid.
A takeoff is where every estimate starts. The estimator "takes off" quantities from the plans and specs: so many cubic yards of concrete, so many linear feet of wall, so many doors, so many outlets. Those quantities are then multiplied by unit costs for material and labor to build the price. If the takeoff is wrong, nothing downstream can fix it.
The terms takeoff and quantity takeoff are used interchangeably. Some estimators say "material takeoff" when they mean only the materials list, with labor priced separately.
How a takeoff is done
- Read the full set first, including specs and addenda, to understand the scope and any alternates.
- Break the work into trades or cost codes, so quantities line up with how the job will be bought and tracked.
- Measure from scaled drawings, either on paper or with digital takeoff software, checking the scale on every sheet.
- Count items (fixtures, devices, doors) and color-mark them so nothing is counted twice.
- Add waste and overlap factors appropriate to each material.
- Note anything unclear as a question or a bid clarification rather than guessing.
A worked example: a slab-on-grade
Say a concrete sub is bidding a 60 by 120 foot warehouse slab, 6 inches thick, with a thickened edge. The slab area is 7,200 square feet. At half a foot thick that is 3,600 cubic feet, which divided by 27 is about 133 cubic yards. The thickened edge runs the 360-foot perimeter, and the estimator calculates another 13 or so yards for it. Adding a waste factor the company has learned from past slabs, the estimator orders closer to 152 yards.
| Item | Quantity |
|---|---|
| Slab area | 7,200 sq ft |
| Slab concrete at 6 in | 133 cu yd |
| Thickened edge | 13 cu yd |
| Total with waste allowance | 152 cu yd |
| Vapor barrier | 7,200 sq ft plus laps |
| Perimeter edge form | 360 lin ft |
Each quantity then gets a unit price and a labor productivity rate. The takeoff also feeds the bill of materials and, after award, the job budget.
Keep the marked-up takeoff sheets after the bid. If the job is won, the project manager uses them to check purchase quantities and to spot scope that was missed. If it is lost, they become a reference for pricing the next similar job.
Common takeoff mistakes
- Wrong scale. A reduced-size sheet measured at full scale throws every number off.
- Missed addenda. An addendum that changes a door schedule never makes it into the count.
- Double counting where two sheets show the same area, such as an enlarged plan.
- No waste factor, or one copied from a different material.
- Scope gaps between trades, such as who carries blocking or firestopping. See scope gap.
Related terms
A takeoff is the first step of estimating and is followed by pricing, markup, and the bid. For a full walkthrough, see how to do a quantity takeoff and how to read construction plans for estimating. Smart Business Automator carries takeoff quantities from the winning estimate into the job budget so the field works from the same numbers; see estimate to project handoff automation.
Frequently asked questions
What is the difference between a takeoff and an estimate?
The takeoff produces quantities. The estimate adds prices, labor, equipment, overhead, and profit to those quantities to arrive at a bid.
Is takeoff software worth it?
For contractors who bid often, digital takeoff usually saves time and reduces counting errors. Small contractors bidding a few jobs a month may do fine with a scale ruler and a spreadsheet.
How accurate does a takeoff need to be?
Accurate enough that quantity errors do not eat the margin. Check large-dollar items twice and use waste factors based on your own job history.
Who does the takeoff on a construction project?
The estimator at each contractor that is bidding. GCs often do their own takeoff of major trades to check sub bids during bid leveling.
