How to Estimate Demolition Takeoff 2026

A demolition takeoff is the measured quantities part of a demolition estimate: the counts, lengths, areas, and volumes your trade bills on. Done by hand it means counting fixtures one by one, tracing walls and floors with a scale wheel, and converting the takeoff to hauling volume on a calculator. Done with on screen takeoff software it means tracing the same outlines with a mouse. Done with AI it means uploading the drawings and getting the same quantities back in seconds, with the math shown for every line so your estimator can check the work instead of doing it.

What You Are Counting

Demolition takeoff splits into selective demolition, where you remove specific items and leave the structure, and total demolition, where you take the whole building down to the slab or dirt. The quantities differ, but you measure them the same way, by assembly and unit.

Surface area removed. Walls, ceilings, floors, and partitions taken down to structure, each in square feet (SF). You measure the face you remove, not the footprint.
Volume removed. Concrete, asphalt, masonry, and soil taken in cubic feet (CF) and converted to cubic yards (CY) for hauling. Walls come off the plan in SF times thickness, slabs in SF times depth.
Fixtures and components. Count by the each (EA): plumbing fixtures, doors, cabinets, light fixtures, HVAC units, and equipment. Pull the count from the demolition keynotes and the fixture schedule.
Linear removals. Pipe, conduit, duct, baseboard, crown, and trim runs taken in linear feet (LF). Measure off the plan, count fittings by the piece.
Utility disconnections. Count of disconnects at water, sewer, gas, electric, and data, plus LF of abandoned line pulled back to the source.
Haul off and disposal. CY of debris and material hauled, with a weight estimate for concrete and asphalt because landfills and recyclers price by the ton.
Salvage and recycling. SF or count of items pulled for reuse or recycling credit, separated from waste because the price and the handling differ.

Units and Scale

Demolition is priced in three units at once: SF for surface removal, CY for volume and hauling, and EA for fixtures and components. You keep all three on the same takeoff because the labor and disposal prices attach to different units. A 100 LF wall, 8 feet tall, 6 inches thick is 800 SF of surface removal and 14.8 CY of volume, and both numbers land on the estimate.

Scale reads off the demolition plan and the existing conditions plan. Most demolition sheets reuse the architectural plan set, so the scale is the same as the original construction drawings, commonly 1/8 inch or 1/4 inch to the foot. Detail sheets run larger. Set and confirm the scale per sheet, and recheck when you jump from plan to section.

Step by Step Takeoff

Collect the demolition and existing conditions sheets. Pull the demolition plan, the demolition keynote legend, the existing conditions plan, and the fixture schedule. The keynotes tell you what gets removed and the schedule gives you the counts.
Separate selective from total demolition first. Mark the scope on the plan before you measure. Total demo is the whole footprint, selective demo is the hashed or noted area only.
Set and verify the scale on every sheet. Match the bar scale on the drawing. Recheck when you switch between plan, section, and detail sheets.
Take off surface removals. Trace walls, ceilings, and floors marked for removal in SF. Deduct openings larger than the note cutoff, commonly 25 SF, but leave small penetrations in. Group by assembly: gypsum partitions, acoustical ceilings, flooring, and so on.
Take off volume removals. Convert wall and slab SF to CF by multiplying by thickness, then to CY. Concrete and asphalt need a weight estimate too, commonly 145 pounds per CF for concrete and 145 pounds per CF for asphalt, so you can quote the hauling by the ton.
Count fixtures and components. Pull doors, frames, windows, plumbing fixtures, light fixtures, cabinets, and equipment by the each off the schedule and the keynotes. Tag each count to its location.
Measure linear removals. Trace pipe, conduit, duct, and trim runs in LF. Count fittings, boxes, and supports by the piece.
Take off utility disconnections. Count each disconnect at the source. Measure LF of abandoned line that has to be pulled back or capped.
Apply waste and swell factors. Demolition debris swells in the truck, commonly 25 to 50 percent for mixed debris and up to 60 percent for concrete rubble. Apply the swell factor to your in place volume to get the hauling volume.
Organize and export. Group quantities by assembly and location. Tag every line to its sheet and keynote. Export to Excel or PDF for pricing.

Manual vs Digital vs AI Takeoff

Manual demolition takeoff uses a scale wheel, highlighter, and a printed set. You trace the hashed demo areas, count fixtures off the schedule, and do the volume and swell math by hand or in a spreadsheet. It works, but it is slow, commonly 30 to 90 minutes per sheet, and the swell factor math is a common source of error.

Digital on screen takeoff swaps the scale wheel for a mouse. You trace the demo outlines, the software computes SF and CF, and you keep the fixture count in a linked spreadsheet. It is faster and cleaner than manual, but you still read every keynote and count every fixture yourself.

AI takeoff reads the demolition plan the way an estimator does. It detects the demo hatch, reads the keynotes, counts the fixtures, and reports SF, CF, CY, and EA with the math shown for every line. Confidence flags mark what to verify, and low confidence lines show the source keynote so you can check in seconds. Your estimator spends time on judgment, like confirming the scope boundary, and lets the software handle the counting.

Common Takeoff Errors

Forgetting the swell factor on hauling. In place volume is not hauling volume, debris expands when loaded.
Forgetting to deduct openings from surface removals. Read the note cutoff and deduct everything above it.
Mixing selective and total demolition scope. Mark the scope boundary before you measure, do not eyeball it.
Double counting fixtures that appear in both the schedule and the keynote legend. Use the schedule as the source of truth.
Missing concealed runs and abandoned lines that are not fully shown on the plan. Chase the details and the existing conditions sheets.
Forgetting utility disconnections. Each disconnect is its own line, count them at the source.
Confusing surface removal SF with floor area SF. A wall is face area, not footprint.

Putting It Together

A clean demolition takeoff ends with quantities organized by assembly and tied to their source sheets: surface removal SF by assembly, volume CY by material, fixture and component counts, linear removals LF, utility disconnect counts, and hauling CY with the swell factor applied. From there pricing is a separate step, you multiply your quantities by unit costs and add labor and disposal. The takeoff itself is just the counting and the measuring, done right, with the math shown so anyone can follow it back to the drawing and the keynote.