> Complete construction estimating methodology — from quantity takeoff to bid submission. Zero dependencies.
| Project Stage | Estimate Type | Accuracy | Basis | Use Case |
|---|---|---|---|---|
| --- | --- | --- | --- | --- |
| Concept | Order of Magnitude | -30% to +50% | SF/unit costs | Go/no-go decisions |
| Schematic | Conceptual/Budget | -15% to +30% | Assembly costs | Budget approval |
| Design Dev | Detailed | -10% to +15% | Quantity takeoff | GMP/bid preparation |
| Construction Docs | Definitive/Bid | -5% to +10% | Full QTO + subs | Lump sum bid |
| Construction | Control | Actual costs | Committed + forecast | Cost management |
project:
name: ""
number: ""
type: residential | commercial | industrial | infrastructure | renovation
delivery: design-bid-build | design-build | CM-at-risk | IPD
location:
city: ""
state: ""
zip: ""
location_factor: 1.00 # RSMeans city cost index / national average
owner: ""
architect: ""
scope:
gross_sf: 0
stories: 0
site_acres: 0
description: ""
schedule:
bid_date: ""
construction_start: ""
substantial_completion: ""
duration_months: 0
estimate:
type: order-of-magnitude | conceptual | detailed | definitive
base_date: "" # Date costs are based on
escalation_rate: 0.04 # Annual construction cost escalation
assumptions:
- ""
exclusions:
- ""
allowances:
- item: ""
amount: 0
| Type | Key Considerations | Typical $/SF Range (2024-2026) |
|---|---|---|
| --- | --- | --- |
| Single Family Residential | Foundation type, finishes grade, energy code | $150-$400/SF |
| Multi-Family | Unit mix, parking ratio, amenities | $200-$450/SF |
| Office (Class A) | Curtain wall, MEP density, TI allowance | $250-$550/SF |
| Retail | Shell vs TI, storefront, grease traps | $150-$350/SF |
| Healthcare/Hospital | Life safety, med gas, shielding | $400-$900/SF |
| K-12 Education | Prevailing wage, hazmat, phasing | $300-$600/SF |
| Warehouse/Distribution | Clear height, slab flatness, dock count | $80-$180/SF |
| Hotel | Star rating drives finish, FF&E budget | $200-$500/SF |
| Infrastructure (road/mile) | Soil conditions, utilities, traffic control | $2M-$10M/mile |
Use CSI MasterFormat 2018 for ALL estimates. Every line item maps to a division.
| Division | Name | Typical % of Total |
|---|---|---|
| --- | --- | --- |
| 01 | General Requirements | 8-12% |
| 02 | Existing Conditions | 1-5% |
| 03 | Concrete | 8-15% |
| 04 | Masonry | 2-6% |
| 05 | Metals (Structural Steel) | 8-15% |
| 06 | Wood, Plastics, Composites | 3-8% |
| 07 | Thermal & Moisture Protection | 4-8% |
| 08 | Openings (Doors/Windows) | 3-7% |
| 09 | Finishes | 8-15% |
| 10 | Specialties | 1-3% |
| 11 | Equipment | 1-5% |
| 12 | Furnishings | 1-5% |
| 13 | Special Construction | 0-3% |
| 14 | Conveying Equipment (Elevators) | 1-4% |
| 21 | Fire Suppression | 2-4% |
| 22 | Plumbing | 4-8% |
| 23 | HVAC | 8-15% |
| 26 | Electrical | 8-15% |
| 27 | Communications | 1-3% |
| 28 | Electronic Safety & Security | 1-3% |
| 31 | Earthwork | 3-8% |
| 32 | Exterior Improvements | 2-6% |
| 33 | Utilities | 2-5% |
line_item:
division: "03"
spec_section: "03 30 00"
description: "Cast-in-Place Concrete - Elevated Slabs"
quantity: 450
unit: CY
unit_cost:
labor: 85.00
material: 165.00
equipment: 25.00
subcontractor: 0.00
total_unit_cost: 275.00
extended_cost: 123750.00
waste_factor: 0.07
adjusted_quantity: 481.5
notes: "4500 PSI, #5 rebar @ 12\" OC EW, 6\" slab"
source: "Sub quote - ABC Concrete (02/15/2026)"
confidence: high | medium | low
| Check | Formula | Flag If |
|---|---|---|
| --- | --- | --- |
| Concrete per SF | Total CY ÷ Building SF | >0.15 CY/SF (unless heavy structure) |
| Steel per SF | Total tons ÷ Building SF | >15 PSF (unless high-rise) |
| Drywall SF | Total drywall SF ÷ Floor SF | <2.0 or >4.0 ratio |
| Electrical per SF | Electrical $ ÷ Building SF | >$35/SF (standard office) |
| Plumbing fixtures | Count vs occupancy | Missing fixtures for code compliance |
| Parking spaces | Per local code requirements | Below minimum ratio |
Cost source hierarchy (most reliable first):
labor_rate_build_up:
trade: "Carpenter"
base_wage: 42.50
fringe_benefits: 18.75 # Health, pension, vacation, training
payroll_taxes: 8.90 # FICA, FUTA, SUTA, workers comp
total_burden: 27.65
burdened_rate: 70.15
productivity_factors:
weather: 1.00 # 1.0 = normal, 1.15 = winter
overtime: 1.00 # 1.0 = straight time, 1.5 = OT
height: 1.00 # 1.0 = ground, 1.10 = >30ft
congestion: 1.00 # 1.0 = open, 1.15 = tight
shift: 1.00 # 1.0 = day, 1.10 = swing, 1.15 = night
adjusted_rate: 70.15
Score each sub quote (use minimum 3 per trade):
| Factor | Weight | 1-5 Score |
|---|---|---|
| --- | --- | --- |
| Price competitiveness | 30% | |
| Scope completeness (covers all spec sections?) | 25% | |
| Qualifications/exclusions (red flags?) | 20% | |
| Past performance/reputation | 15% | |
| Bond capacity/insurance | 10% | |
| Weighted Total | 100% |
Red flags in sub quotes:
Crew Daily Cost = Σ(Workers × Daily Rate) + Equipment Daily Cost
Crew Daily Output = Units per 8-hour day (from labor standards)
Unit Cost = Crew Daily Cost ÷ Crew Daily Output
Example — Concrete Placement Crew:
| Item | Duration-Based? | Typical Range |
|---|---|---|
| --- | --- | --- |
| Project Manager | Yes | $12K-$18K/month |
| Superintendent | Yes | $10K-$16K/month |
| Project Engineer | Yes | $8K-$12K/month |
| Field Office (trailer) | Yes | $1K-$3K/month |
| Temporary utilities | Yes | $2K-$5K/month |
| Temporary toilets | Yes | $200-$500/month each |
| Dumpsters/waste removal | Yes | $1K-$4K/month |
| Safety equipment/supplies | Yes | $500-$2K/month |
| Small tools & consumables | Lump | 1-2% of labor |
| Final cleaning | Lump | $0.15-$0.50/SF |
| Permits (building) | Lump | Varies by jurisdiction |
| Insurance (Builder's Risk) | Lump | 0.5-1.5% of cost |
| Performance/Payment Bond | Lump | 1-3% of contract |
| Testing & inspection | Lump | 0.5-1.5% of cost |
| As-built documentation | Lump | $5K-$25K |
| Commissioning support | Lump | $10K-$50K |
Rule of thumb: General conditions = 8-15% of direct costs (lower for large projects, higher for small/complex).
markup_calculation:
direct_costs: 2500000
general_conditions:
percentage: 0.10
amount: 250000
subtotal_1: 2750000
overhead:
percentage: 0.05 # Home office overhead
amount: 137500
subtotal_2: 2887500
profit:
percentage: 0.05 # Varies by market/risk
amount: 144375
subtotal_3: 3031875
contingency:
design_contingency: 0.05 # For incomplete drawings
construction_contingency: 0.03 # For unforeseen conditions
amount: 242550
bond:
percentage: 0.015
amount: 49118
escalation:
rate: 0.04 # Annual
months_to_midpoint: 8
amount: 88536
total_estimate: 3412079
cost_per_sf: 341.21 # For 10,000 SF building
| Estimate Type | Design Contingency | Construction Contingency |
|---|---|---|
| --- | --- | --- |
| Order of Magnitude | 15-25% | 10-15% |
| Conceptual | 10-15% | 5-10% |
| Detailed | 3-8% | 3-5% |
| Definitive/Bid | 0-3% | 2-3% |
Contingency is NOT profit padding. Track and justify every contingency draw.
Score 1-5 for each (minimum 30 to bid):
| Factor | Weight | Score |
|---|---|---|
| --- | --- | --- |
| Project type experience | 3x | |
| Client relationship/history | 2x | |
| Current workload capacity | 3x | |
| Geographic fit | 2x | |
| Profit potential | 3x | |
| Competition level (fewer = better) | 2x | |
| Risk profile (lower = better) | 3x | |
| Schedule feasibility | 2x | |
| Bonding capacity available | 2x | |
| Weighted Total | /110 |
48 hours before:
Day of bid:
Market conditions affect markup:
Bid spread analysis (track your results):
Bid Spread = (Your Bid - Low Bid) ÷ Low Bid × 100
| System | VE Opportunity | Typical Savings | Risk Level |
|---|---|---|---|
| --- | --- | --- | --- |
| Structural | Steel vs concrete frame | 5-15% of structure | Medium |
| Foundations | Spread vs mat vs piles | 10-30% of foundation | High (geotech dependent) |
| Envelope | Curtain wall vs storefront | 15-30% of facade | Low-Medium |
| Roofing | TPO vs modified bitumen | 10-20% of roofing | Low |
| Mechanical | VAV vs VRF | 10-25% of HVAC | Medium |
| Electrical | LED fixtures, panel optimization | 5-15% of electrical | Low |
| Finishes | Material substitutions | 10-40% of finishes | Low |
| Site | Reduce import/export of soil | 10-30% of sitework | Medium |
ve_item:
number: VE-001
description: "Substitute VRF system for conventional VAV"
division: "23"
original:
description: "VAV air handling system with ductwork"
cost: 850000
proposed:
description: "Variable Refrigerant Flow (VRF) with DOAS"
cost: 680000
savings: 170000
savings_pct: 20%
impact:
schedule: "Reduces mechanical rough-in by 2 weeks"
quality: "Better zone control, lower operating cost"
maintenance: "Higher per-unit cost but less ductwork"
code_compliance: "Meets ASHRAE 90.1, verify local amendments"
risk: medium
recommendation: accept | reject | modify
requires_redesign: yes | no
redesign_cost: 15000
net_savings: 155000
Contractor markup on changes (typical):
| Tier | Self-Performed Work | Subcontractor Work |
|---|---|---|
| --- | --- | --- |
| Overhead | 10% | 5% |
| Profit | 10% | 5% |
| Bond | Add actual % | Add actual % |
Time & Material (T&M) documentation requirements:
change_order:
number: CO-001
date: ""
description: ""
reason:
type: owner-directed | unforeseen-condition | design-error | code-change | scope-clarification
rfi_number: ""
cost_breakdown:
labor:
hours: 0
rate: 0
total: 0
material:
items: []
total: 0
equipment:
items: []
total: 0
subcontractor:
items: []
total: 0
direct_cost: 0
markup: 0.15
total_cost: 0
schedule_impact:
days: 0
critical_path: yes | no
explanation: ""
status: pending | approved | rejected | negotiating
Budget at Completion (BAC) = Total budget
Planned Value (PV) = Budgeted cost of work scheduled
Earned Value (EV) = Budgeted cost of work performed
Actual Cost (AC) = Actual cost of work performed
Schedule Performance Index (SPI) = EV / PV
>1.0 = ahead of schedule
<1.0 = behind schedule
Cost Performance Index (CPI) = EV / AC
>1.0 = under budget
<1.0 = over budget
Estimate at Completion (EAC) = BAC / CPI
Variance at Completion (VAC) = BAC - EAC
cost_report:
project: ""
period: ""
report_date: ""
summary:
original_contract: 0
approved_changes: 0
pending_changes: 0
current_budget: 0
committed_cost: 0 # Subcontracts + POs
actual_cost_to_date: 0
forecast_to_complete: 0
estimate_at_completion: 0
variance: 0
contingency_remaining: 0
schedule:
percent_complete: 0
spi: 0
cpi: 0
days_ahead_behind: 0
cash_flow:
billed_to_date: 0
collected_to_date: 0
retention_held: 0
risk_items:
- description: ""
potential_cost: 0
probability: high | medium | low
mitigation: ""
| Signal | What It Means | Action |
|---|---|---|
| --- | --- | --- |
| CPI < 0.95 in first 25% | Systemic cost overrun | Root cause analysis NOW |
| Contingency burn > schedule % | Burning contingency too fast | Tighten change management |
| >5 pending COs unsigned | Cash flow risk, scope dispute | Escalate to PM/owner |
| Sub invoices > committed | Sub performing extra work | Verify scope, issue CO or stop work |
| Retainage release requests early | Sub cash flow problems | Monitor closely, check lien waivers |
Add these factors to renovation estimates:
Critical factors:
sitework_checklist:
geotechnical:
- Soil bearing capacity
- Water table depth
- Rock depth (blasting vs mechanical?)
- Contamination (Phase I/II ESA results)
earthwork:
cut_cy: 0
fill_cy: 0
import_export: 0 # Net CY to haul
haul_distance_miles: 0
compaction_required: standard | proctor_95 | proctor_98
utilities:
water_tap_fee: 0
sewer_tap_fee: 0
fire_line: 0
storm_detention: required | not_required
paving:
asphalt_sy: 0
concrete_sy: 0
curb_lf: 0
striping_lf: 0
landscape:
sod_sf: 0
trees_ea: 0
irrigation: yes | no
erosion_control: silt_fence | inlet_protection | retention_pond
| System | $/SF Benchmark (Commercial Office) | Flag If |
|---|---|---|
| --- | --- | --- |
| HVAC | $25-$50/SF | >$55 or <$20 |
| Plumbing | $12-$25/SF | >$30 or <$8 |
| Fire Protection | $4-$8/SF | >$10 or <$3 |
| Electrical (power) | $18-$35/SF | >$40 or <$12 |
| Low voltage/data | $5-$12/SF | >$15 or <$3 |
| Total MEP | $64-$130/SF | >$150 or <$46 |
Future Cost = Current Cost × (1 + Annual Rate) ^ (Months to Midpoint ÷ 12)
Recent escalation trends (US):
Always escalate to the MIDPOINT of construction, not the start.
Local Cost = National Average Cost × City Cost Index
Sample RSMeans City Cost Indices (100 = national average):
| City | Index | City | Index | |
|---|---|---|---|---|
| --- | --- | --- | --- | --- |
| New York, NY | 130-145 | Dallas, TX | 88-95 | |
| San Francisco, CA | 125-140 | Atlanta, GA | 90-97 | |
| Boston, MA | 115-130 | Phoenix, AZ | 88-94 | |
| Chicago, IL | 110-120 | Denver, CO | 95-105 | |
| Seattle, WA | 108-118 | Nashville, TN | 88-95 | |
| Washington, DC | 100-110 | Charlotte, NC | 85-92 | |
| Miami, FL | 92-100 | Houston, TX | 85-93 | |
| Minneapolis, MN | 105-112 | Rural areas | 70-85 |
| Dimension | Weight | Criteria |
|---|---|---|
| --- | --- | --- |
| Scope completeness | 20 | All spec sections priced, no gaps, exclusions documented |
| Quantity accuracy | 20 | QTO verified, cross-checks pass, waste factors applied |
| Pricing basis | 15 | 3+ sub quotes per trade, current material prices, documented sources |
| Indirect costs | 10 | GCs detailed (not lump), schedule-based items tied to duration |
| Markup appropriateness | 10 | Market-competitive, risk-adjusted, contingency justified |
| Documentation | 10 | Assumptions listed, basis of estimate narrative, organized by division |
| Adjustments | 10 | Location factor applied, escalation to midpoint, seasonal factors |
| Presentation | 5 | Professional format, clear summary, alternates separated |
Grading: 90+ = Bid-ready | 75-89 = Needs refinement | 60-74 = Major gaps | <60 = Redo
| # | Mistake | Prevention |
|---|---|---|
| --- | --- | --- |
| 1 | Missing addenda | Checklist: log every addendum, initial when incorporated |
| 2 | Incomplete sub scope | Write scope sheets with inclusions AND exclusions |
| 3 | Wrong labor rates | Verify union vs open shop, prevailing wage, location |
| 4 | No escalation | ALWAYS escalate to construction midpoint |
| 5 | Lump sum general conditions | Detail every line item tied to schedule |
| 6 | Ignoring phasing | Multi-phase = mobilize/demobilize multiple times |
| 7 | Missing temporary work | Shoring, dewatering, winter protection, dust control |
| 8 | Under-priced site conditions | Get geotech report BEFORE estimating foundations |
| 9 | Scope gaps between trades | Who installs the backing for the TV mount? |
| 10 | Not reading the fine print | Liquidated damages, retainage, payment terms |
Occupied building renovation:
Remote/rural project:
Fast-track schedule:
Public/government work:
Design-Build:
| Command | Action |
|---|---|
| --- | --- |
| "Estimate this project" | Run full estimate workflow from Phase 1 |
| "Price [division/trade]" | Develop unit costs for specific trade |
| "Check my quantities" | Run QTO verification cross-checks |
| "Value engineer [system]" | Generate VE alternatives with savings |
| "Write change order for [scope]" | Generate CO with pricing and backup |
| "Compare sub quotes for [trade]" | Score and compare subcontractor bids |
| "Monthly cost report" | Generate EVM-based cost report |
| "Bid/no-bid analysis for [project]" | Run decision scorecard |
| "Location adjust to [city]" | Apply RSMeans location factor |
| "Escalate costs to [date]" | Calculate escalation to future midpoint |
| "Review my estimate" | Run 100-point quality rubric |
| "Generate bid summary" | Format estimate for bid submission |
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