Before you can price a construction project, you have to know exactly what you are building. That is what a quantity takeoff is for.

A quantity takeoff — often called a QTO or material takeoff — is the process of measuring and listing every item of work shown on a set of construction drawings. It is the first step in building an accurate estimate, and it is the step where most estimating errors begin.

What Is a Quantity Takeoff?

A quantity takeoff is a detailed measurement of all the materials, labor units, and work items required to complete a construction project. Every item is measured in the appropriate unit — linear feet, square feet, cubic yards, each — and organized by trade or CSI division.

A complete quantity takeoff for a commercial project might include:

• Concrete — cubic yards of footings, slabs, walls, and columns
• Masonry — square feet of block or brick, number of units
• Structural steel — tons of steel, linear feet of beams and columns
• Framing — linear feet of studs, plates, headers, and blocking
• Drywall — square feet of board, linear feet of metal framing
• Roofing — squares of roofing material, linear feet of flashing
• Mechanical, Electrical, Plumbing — fixture counts, linear feet of pipe and conduit

Why Quantity Takeoffs Matter

The accuracy of your estimate is only as good as your takeoff. If you miss items or measure incorrectly, your bid will be off — and you will either lose the job or lose money on it.

A precise quantity takeoff:

• Prevents scope gaps — ensures nothing is missed in the bid
• Supports accurate pricing — correct quantities lead to correct material and labor costs
• Speeds up the estimating process — organized takeoffs make pricing faster
• Provides documentation — a defensible record if scope disputes arise
• Enables value engineering — knowing exact quantities makes it easier to evaluate alternatives

How a Professional Quantity Takeoff Is Performed

Professional estimators use digital takeoff software to measure directly from PDF drawings. Tools like Bluebeam Revu, PlanSwift, and On-Screen Takeoff allow estimators to:

• Scale drawings to verify accuracy
• Measure linear, area, and count items with precision
• Color-code items to track what has been measured
• Export quantities to estimating spreadsheets or software

The process follows a systematic approach — typically working through the drawings trade by trade, floor by floor — to ensure complete coverage.

Step 1: Verify Drawing Scale

Before measuring anything, the estimator confirms that the drawing scale is correct. A miscalibrated scale will throw off every measurement that follows.

Step 2: Organize by Trade or CSI Division

Quantities are organized by trade (concrete, framing, drywall, etc.) or by CSI MasterFormat division. This makes it easier to price the work and hand off quantities to subcontractors for pricing.

Step 3: Measure and Count

Working systematically through the drawings, the estimator measures every item of work. Linear items (pipe, conduit, framing) are measured in feet. Area items (drywall, flooring, roofing) are measured in square feet or squares. Volume items (concrete, earthwork) are measured in cubic yards.

Step 4: Apply Waste Factors

Raw measurements from the drawings rarely equal the amount of material you will actually order. Waste factors account for cuts, overlaps, and material that cannot be reused. Standard waste factors vary by material and installation method.

Step 5: Organize and Deliver

The completed takeoff is organized into a clear, usable format — typically a spreadsheet or estimating software export — that can be priced quickly and reviewed for accuracy.

Common Quantity Takeoff Mistakes

Even experienced estimators make takeoff errors. The most common include:

• Missing items — work shown in the specifications but not clearly on the drawings
• Wrong scale — measuring from a drawing that has been printed at a non-standard scale
• Forgetting waste — ordering exactly what the drawings show, then running short on material
• Double-counting — measuring the same item twice when it appears on multiple drawing sheets
• Ignoring addenda — missing scope changes issued after the original drawings were released

Outsourcing Your Quantity Takeoffs

For many contractors, performing takeoffs in-house is not always practical. Bid volume, tight deadlines, and specialty trade work can overwhelm even well-staffed estimating departments.

Outsourcing quantity takeoffs to a professional firm offers several advantages:

Speed — Professional estimators can complete takeoffs faster than most in-house teams, with 48–72 hour turnaround on most projects.

Accuracy — Dedicated estimators who perform takeoffs every day develop a level of precision that is hard to match with part-time estimating staff.

Capacity — When bid volume spikes, outsourced takeoffs let you pursue more work without adding permanent headcount.

Specialty trades — For trades outside your core expertise, a professional firm brings the knowledge to measure and price the work correctly.

What to Expect from a Professional Takeoff Service

When you work with a professional estimating firm, you should receive:

• A complete, organized quantity list by trade or CSI division
• Clear documentation of what was measured and how
• Waste factors applied to material quantities
• A format that is easy to price and review
• Turnaround time that meets your bid deadline

Union Estimating provides quantity takeoff services across all trades — concrete, framing, drywall, electrical, plumbing, HVAC, roofing, masonry, and more — with 48–72 hour turnaround and a format ready for immediate pricing.

The Bottom Line

A quantity takeoff is not just a list of numbers. It is the foundation of every accurate estimate and every winning bid. Getting it right requires attention to detail, knowledge of construction methods, and the right tools.

Whether you perform takeoffs in-house or work with a professional service, the goal is the same: complete, accurate quantities that give you the confidence to price competitively and win profitable work.