Demo Estimating — Module 3
Demolition Takeoff & Quantity Measurements
Convert drawings into defendable quantities. Measure the right units, apply thickness/weight factors, and translate takeoffs into debris, trucking, labor, and potential scrap credits.
🎯 Learning Objectives
- Choose between manual and digital takeoff methods and document your source.
- Measure by the unit that drives production & disposal (SF, CY, LF, EA, TON).
- Apply thickness and density to convert area into volume and weight.
- Capture MEP removals and evaluate salvage credits without risking scope gaps.
- Build a traceable takeoff log that stands up to review & clarifications.
🖥️ Manual vs. Digital Takeoff Methods
Select your approach by job size, document quality, and timeline. Always save proof (colored markups, snapshots).
- Manual: scale rulers, highlighters, and printed plans — fast for small changes and field markups.
- Digital: Bluebeam, PlanSwift, On-Screen Takeoff — accurate, repeatable, and exportable to Excel.
- Verify sheet scale, datum, and legend. For PDFs, re-calibrate scale per sheet if needed.
- Store exported takeoff layers & counts with naming like
AD1.02_DemoWalls_Z1_v1.png.
📌 Hybrid Wins: quick manual checks + digital totals for submittal documentation.
📐 Measuring & Quantifying Materials for Removal
Use units aligned with effort and disposal:
- Concrete slabs/foundations: measure SF with thickness → convert to CY and tons.
- Masonry: SF (face) + thickness → CF/CY; consider grout/rebar; note lintels/bearing.
- Steel: count beams/columns by section; weigh by tables or use TON via supplier data.
- Wood framing: LF/SF, board-feet for heavy timber; note nails/fasteners (time impact).
- Finishes: drywall SF (each side), ACT ceiling SF, flooring SF with layers (mastic, underlayment).
Typical Densities (ROM)
- Concrete: ~2.0 ton/CY
- Masonry (CMU/brick): ~1.0–1.4 ton/CY
- Mixed C&D: ~0.35–0.55 ton/CY
- Gypsum: ~0.35 ton/CY
- Wood framing: ~0.25 ton/CY
Common Conversions
- CY = (SF × Thickness(in)/12) ÷ 27
- TON = CY × Density(ton/CY)
- Loads = CY ÷ Truck Cap (CY) → round up
⚙️ MEP System Removals
Capture removals and potential credits without risking life-safety or code issues.
- Ductwork: LF by size or weight (for recycle); note insulation/liner handling.
- Electrical: EA (fixtures/panels) + LF conduit; segregate copper/AL; maintain FA until approved.
- Plumbing: fixture counts; LF of material by type (copper/PVC/CI); cap points and traps.
- Include disposal vs. salvage as separate lines; record scrap tickets post-award.
🛡️ Price disconnects and compliance as explicit lines; don’t bury them in production.
📋 Sample Takeoff Log (Excerpt)
| Area / Tag | Item | Unit | Qty | Notes / Method |
|---|---|---|---|---|
| Zone A | GWB Partition (3-5/8") | SF | 1,950 | Selective; protect MEP |
| Zone B | Concrete Slab (4") | CY | 28 | Sawcut & break; water control |
| Roof | RTUs (salvage) | EA | 2 | Crane picks; EPA refrigerant recovery |
✍️ Suggested Clarifications (copy/paste)
- Quantities based on demo sheets and field conditions at bid time; deviations priced per unit rates.
- Disposal at licensed facilities; tipping fees assumed as shown; manifests provided at closeout.
- Scrap credits shown separately; title transfers at pick-up; weights verified by scale tickets.
- Disconnects by licensed trades; demo starts after written shutdown confirmations.
🧰 Takeoff & Quantity Mini Tools
🧮 Debris Converter (SF → CY → Tons)
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🪚 Sawcut & Break Planner
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🚪 Openings & Infill Estimator
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🚚 Mixed C&D Trucking Estimator
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♻️ MEP Scrap Credit (ROM)
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