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Plumbing Case Studies

Plumbing Case Studies

Plumbing Estimating Class

🧠 Module 9: Case Studies & Real-Life Applications

Apply everything you’ve learned on real project scenarios—from scope review and takeoff to pricing, risk, and proposal packaging.

📘 Overview

This capstone module uses four distinct case studies—Multifamily Core/Shell, TI Restaurant, Outpatient Clinic, and K-12 Renovation—to practice plan reading, digital takeoff, assemblies/BOM, vendor quote leveling, labor/productivity, risk, and proposal formatting. Use the downloadable packets below to work end-to-end.

🎯 Learning Objectives

  • Translate drawings/specs into a clean scope & clarifications list.
  • Complete a reproducible takeoff with assemblies and cost codes.
  • Level supplier quotes and select preferred + backup vendors.
  • Build pricing with DC → Overhead → Profit (margin) and alternates.
  • Package a client-ready proposal with allowances, unit prices, and exclusions.

Case A — Multifamily Core/Shell (4-Story)

  • Focus: Riser diagrams, roof drains, pressure zones, fixture rough-ins.
  • Tasks: Takeoff CW/HW/DWV risers & mains; roof/storm leaders; fixture kits per typical unit.
  • Deliverables: BOM CSV, quote leveling, scope letter with alternates for trim upgrades.

Case B — Tenant Improvement Restaurant

  • Focus: Grease waste, interceptors, floor sink layouts, gas piping.
  • Tasks: Count fixtures; takeoff GW vs. DWV; size gas runs by equipment schedule.
  • Deliverables: Allowances for equipment connections; alternates for grease interceptor models.

Case C — Outpatient Clinic (Healthcare)

  • Focus: Med-gas coordination (if present), reduced work hours, infection control.
  • Tasks: Plan shutdowns; add temp services; factor productivity impacts.
  • Deliverables: Risk register; phased schedule notes; unit prices for add/omit fixtures.

Case D — K-12 Renovation (Occupied)

  • Focus: Night/weekend work, security, temporary facilities, ADA retrofits.
  • Tasks: Segment takeoff by phase; add temp restrooms/water points.
  • Deliverables: Phased SOV; clarifications; schedule constraints in proposal.

🧩 Workflow Checklist (Use for Any Case)

  1. Scope Review: Read plans/specs; list inclusions, exclusions, and assumptions.
  2. Digital Takeoff: Calibrate scale; color-code CW/HW/DWV/Storm/Gas; count fixtures/valves.
  3. Assemblies: Apply pipe-by-size and fixture kits; generate BOM + labor.
  4. Quotes: Request two supplier quotes per major package; level for cost/lead/scope.
  5. Pricing: DC → Overhead → Profit (margin). Separate alternates and allowances.
  6. Proposal: Fill bid form; add unit prices, clarifications, schedule constraints.
  7. QA: Cross-check counts to schedules; reconcile risers vs. floor plans; math audit.

📂 Module 9 Downloads & Case Packets

Copy from the blocks below and save as CSV/TXT for your spreadsheets or software. Use one packet per case.

📁 Case Packet — Index (TXT)

/01_Plans (PDFs)
/02_Takeoff_Snapshots (PDF)
/03_BOM_Exports (CSV)
/04_Quotes (PDF/CSV)
/05_Leveling (CSV)
/06_Pricing (XLSX/CSV)
/07_Proposal (PDF)
/08_QA_Checks (TXT)

🚿 Fixture Schedule — Seed (CSV)

Tag,Description,Supply,Drain,Mount,Notes
WC,Water Closet,1/2" CW,4" DWV,Floor,ADA @ select rooms
LAV,Lavatory,3/8" CW/HW,1-1/4" Trap,Wall,Mixing valve per spec
FD,Floor Drain,-,2" DWV,Floor,Trap primer at janitor rooms
RD,Roof Drain,-,4" Storm,Roof,Clamping ring, dome

📏 Takeoff Worksheet (CSV)

System,Size,UoM,Qty,Assembly,Cost Code,Notes
CW,1",LF,,1" Cu Press LF,15-100,
HW,3/4",LF,,3/4" Cu Press LF,15-100,
DWV,4",LF,,4" PVC DWV LF,15-100,
Fixtures,WC,EA,,WC Kit (R+T),15-200,
Storm,RD-110,EA,,Roof Drain Set,15-200,

⚖️ Quote Leveling — Template (CSV)

Item,Spec,Vendor A $,Vendor B $,Vendor C $,Chosen,Lead,Scope Notes,Exceptions
1" Cu Press LF,Type L,,,,,, 
4" PVC DWV LF,Sch 40,,,,,, 
Roof Drain Set,Spec RD-110,,,,,, 
WC Kit,Model A or Equal,,,,,,

💵 Pricing Sheet — DC → OH → Margin (CSV)

Category,Notes,Direct Cost ($),OH %,Margin %,Final Price ($)
Material,From BOM,,,, 
Labor,From assemblies (MH × rate),,,,
Equipment/Small Tools,, ,,, 
Subcontract (if any),,,,
Subtotal DC,, ,,, 
Apply Overhead,, ,,, 
Apply Margin (Price = Subtotal ÷ (1 − Margin%)),,,,
Alternates (Add/Deduct),Describe separately,,,,
Allowances,Describe scope & trigger,,,,
Total Proposal,,, ,

📜 Proposal Outline (Copy/Paste)

• Cover & Bid Summary (Project, Date, Contact)
• Scope Summary (Systems, Areas, Spec Sections)
• BOM & Labor Summaries (no unit $)
• Alternates (list each add/deduct)
• Allowances (trigger & amount)
• Unit Prices (common adds/omits)
• Clarifications / Exclusions
• Schedule Constraints / Work Hours
• Quote Appendix (vendor, date, terms)

✅ Scoring Rubric (TXT)

Scope & Clarifications .......... 20%
Digital Takeoff Accuracy ........ 25%
Assemblies & BOM Integrity ...... 20%
Quote Leveling & Selection ...... 10%
Pricing Math (DC→OH→Margin) ..... 15%
Proposal Formatting ............. 10%
Pass ≥ 75% (No single category < 50%)

🧪 Practice Assignments (Pick 2+)

  1. Case A: Complete riser takeoff & fixture kit counts; export BOM & labor, map cost codes.
  2. Case B: Build grease waste vs. sanitary BOM; price two alternates for interceptor size.
  3. Case C: Add productivity factors for reduced work hours; submit risk/allowance plan.
  4. Case D: Phase the SOV by area; add unit prices for add/omit fixtures and pipe LF.
  5. All Cases: Deliver a client-ready proposal PDF with quote appendix and clarifications.

👩‍🏫 Teacher Notes (Facilitation Guide)

  • Timing: 15 min review, 45–60 min worktime, 15 min share-outs per case.
  • Focus: Audit trail—snapshots, CSV exports, quote PDFs attached to proposal.
  • Feedback: Use the rubric; return one “strength” and one “upgrade” per category.

When you’ve completed two case studies and packaged your proposals, proceed to the Final Test to earn your course certificate.