Worked Example: Class 5 to Class 3 Estimate

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This page walks through a complete estimating sequence — from the first phone call through a GMP proposal — using a single realistic project. Every number is shown, every decision is explained, and every place where senior judgment is required is flagged.

Read this alongside Phase-by-Phase Workflow, which covers the process steps. This page covers the numbers.

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The Project

Project: Midwest Beverage Co. — Production Line Addition Owner: Regional still beverage manufacturer (juices, teas, functional drinks) Location: Chicago, IL metropolitan area Scope: 20,000 SF addition to existing 80,000 SF beverage processing facility + installation of one new 600 BPM still beverage filling line Delivery: Design-Build (GC as design-builder; A/E and process engineer engaged by GC) Schedule: GMP in 10 weeks; construction 14 months Pricing date: Q1 2026

What the owner told you (Day 1, phone call):

• “We need to add a filling line. Probably around 600 bottles per minute for 20 oz still beverages.”
• “We’ll need a new building addition — maybe 20,000 SF.”
• “We want to keep running during construction.”
• “We’d like a number by Friday.”

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Phase 1: Class 5 ROM (Day 1–2)

What You Have

• Project narrative (phone call)
• Satellite photo of the facility from Google Maps
• Owner’s previous project costs (“we built a similar addition 4 years ago for about $9M but that was before inflation”)
• No drawings. No equipment quotes. No geotech.

Method: $/SF Parametric + Equipment ROM

Step 1: Classify the project and select the benchmark.

This is a brownfield F&B beverage filling line addition. From Food and Beverage:

• “Expansion line addition (existing facility): $150–$350/SF (TIC)”
• This range includes building + process utilities but NOT the major filling line equipment, which is priced separately.

Chicago is a union market. Apply a market premium to the mid-range: use $200/SF for the building and utility scope.

Step 2: Price the building and utilities.

Item	Calculation	Amount
Building + process utilities (parametric)	20,000 SF × $200/SF	$4,000,000

Step 3: Price the equipment.

Owner says 600 BPM still beverage filling line. Based on experience and market knowledge:

• Complete filling line (filler, capper, labeler, inspector, case packer, palletizer, stretch wrapper, accumulation conveyors) at 600 BPM: $1.5M–$2.2M FOB for this type and rate.
• Use $1.8M FOB as the mid-point.
• Installation factor: 1.5× FOB for a complete filling line (mechanical hookups, electrical, integration): $2.7M TIC for equipment.

Wait — the $200/SF parametric for the building already includes typical process utilities for this project type. It does NOT include the specific filling line equipment. Use the equipment separately.

Step 4: Add soft costs.

Soft costs (design/engineering + permits + insurance + testing): typically 10–14% for a brownfield F&B project. Use 12%.

Item	Calculation	Amount
Building + utilities	20,000 SF × $200/SF	$4,000,000
Filling line (FOB)	ROM	$1,800,000
Filling line installation	0.5 × FOB	$900,000
Subtotal before soft costs		$6,700,000
Soft costs (12%)	$6,700,000 × 0.12	$804,000
Subtotal before contingency		$7,504,000

Step 5: Apply Class 5 contingency.

AACE Class 5 accuracy: -50% / +100%. For a brownfield project with unknown conditions, use the higher end of contingency: 35%.

Item	Amount
Subtotal before contingency	$7,504,000
Class 5 contingency (35%)	$2,626,000
CLASS 5 ROM	$10,130,000

How to present this:

“ROM estimate: approximately $10M, with a Class 5 accuracy range of $7M–$15M. This is based on parametric benchmarks and a rough equipment estimate. Accuracy improves significantly once we have a floor plan and equipment vendor quotes.”

Do NOT: Give a single number without the range. Do NOT say “the project costs $10M.” Say “the ROM is $10M with a ±range.”

Senior judgment applied here:

• Choice of $200/SF (mid-to-upper range) vs. $175/SF (mid-range). Chicago union market, brownfield premium, and beverage utility complexity all push toward the upper end.
• Equipment FOB of $1.8M. A junior estimator will look up “beverage filling line cost” and find wide variance. A 600 BPM still beverage line for 20 oz PET bottles is a commodity machine — this is reasonable.
• Contingency of 35% vs. 25%. With no geotech, no drawings, and a brownfield site, 35% is appropriate.

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Phase 2: Class 4 Feasibility (Weeks 3–4)

What You Have Now

• Preliminary floor plan (30% sketch — enough to verify 20,000 SF and room layout)
• Owner’s equipment list: 1 filling line, 600 BPM still beverage, 20 oz PET; owner has sent an RFQ to KHS and Krones
• Preliminary process utility sizing from the process engineer: steam (2,000 lb/hr), CAS (200 SCFM), chilled water (120 tons)
• Budget quotes from the mechanical sub and electrical sub (30-day verbal estimates)
• Filling line vendor budget quote received from KHS: $1,620,000 FOB

Method: Equipment-Factored + Building Assembly + Utility Packages

Now you price each major system separately, using actual vendor data where you have it.

Equipment:

Item	Source	Amount
Filling line FOB (KHS budget quote)	Vendor	$1,620,000
Installation (0.5 × FOB)	Factor	$810,000
Equipment subtotal		$2,430,000

Building — assembly level from preliminary floor plan:

Item	Quantity	Rate	Amount
Metal building structure	20,000 SF	$20/SF	$400,000
Foundation / slab on grade	20,000 SF	$5/SF	$100,000
Building envelope (walls + roof)	20,000 SF	$23/SF	$460,000
Doors, hardware, accessories	LS	—	$45,000
Building subtotal			$1,005,000

Process utilities — preliminary sizing:

Item	Basis	Amount
Steam system (tie-in from existing boiler, 20,000 SF distribution)	$8/SF	$160,000
Compressed air (header extension + dryer upgrade, 200 SCFM)	$10,000/SCFM × 200	$200,000
Chilled water (tie-in + distribution, 120 tons)	$600/ton	$72,000
CIP skid (1 CIP skid for filling line)	Budget	$175,000
Process drains + sanitary floors	20,000 SF × $12/SF	$240,000
Utilities subtotal		$847,000

Mechanical and electrical subs:

Item	Source	Amount
HVAC (budget quote from mechanical sub)	Sub 30-day verbal	$265,000
Plumbing (process drains)	Sub 30-day verbal	$185,000
Electrical — MCC, feeders, lighting (budget quote from electrical sub)	Sub 30-day verbal	$385,000
MEP subtotal		$835,000

Site/civil (minimal — brownfield, existing pavement adequate):

Item	Amount
Minor site grading + tie-in to existing pavement	$75,000

General Conditions: 5% of direct cost

Item	Basis	Amount
General conditions	5% × $5,192,000	$260,000

Direct cost subtotal:

Category	Amount
Equipment	$2,430,000
Building	$1,005,000
Process utilities	$847,000
MEP	$835,000
Site/civil	$75,000
General conditions	$260,000
Direct cost subtotal	$5,452,000

Soft costs:

Item	Amount
Design/engineering (8% of direct)	$436,000
Permits + insurance + testing	$65,000
Contractor fee (5% of direct)	$273,000
Soft cost subtotal	$774,000

Subtotal before contingency: $6,226,000

Class 4 contingency (20%): $1,245,000

CLASS 4 ESTIMATE: $7,471,000

Presented as: $7.5M, accuracy range $6M–$9.5M (AACE Class 4)

Why did the estimate drop from $10M to $7.5M?

• The parametric $/SF in Class 5 used the upper-middle of a wide range; it included headroom for a more complex utility scope.
• The KHS equipment quote came in at the lower end of the FOB range ($1.62M vs. $1.8M estimated).
• The process engineer’s utility sizing confirmed this is a relatively low-complexity beverage operation — steam load is modest, no ammonia refrigeration, no CIP cleaning of complex circuits.
• The $10M ROM was not wrong. A Class 5 estimate for this project type with no information SHOULD carry a large range. $7.5M is within the -50%/+100% accuracy of $10M.

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Phase 3: Class 3 GMP Candidate (Weeks 8–10)

What You Have Now

• 35% design drawings: preliminary floor plan, grading plan, structural framing concept, electrical one-line, mechanical HVAC concept
• P&ID: 60% complete; equipment and major piping confirmed; some instrument tags still TBD
• Sub quotes: formal packages sent at Week 5; quotes received from 2–3 subs per trade
• Equipment: KHS filling line quote firmed at $1,625,000 FOB; payment terms 30%/30%/30%/10%
• Geotech report received: soil bearing capacity confirmed at 2,500 PSF (adequate for this project)
• No hazmat found (Phase I ESA complete; Phase II not needed)
• Key discovery: existing electrical switchgear at 70% capacity; new 2,000A MCC required at $402,000 (confirmed by sub)

Method: Bottom-Up by CSI Division with Sub Quotes

Detailed estimate:

Division	Description	Amount
01	General Conditions — 14 month superintendent + PM + facilities	$372,000
02/31	Site work — minor; tie-in to existing pavement, new curb	$62,000
03	Concrete — 20,000 SF SOG sanitary spec ($8.50/SF) + 6 equipment pads	$197,000
05	Structural steel — metal building frame, 20,000 SF @ $19/SF	$380,000
06/07	Building envelope — metal wall panels + TPO roof	$460,000
08	Doors, windows, hardware	$62,000
09a	FRP wall panels — wet process area, 4,000 SF @ $14/SF	$56,000
09b	Epoxy floor — wet areas, 6,000 SF @ $10/SF	$60,000
09c	Standard floor — dry areas, 14,000 SF @ $3.50/SF	$49,000
22a	Process drains + floor drain system	$185,000
22b	Domestic plumbing	$38,000
23	HVAC — food zone AHUs + exhaust (sub quote, low bid)	$278,000
26	Electrical — 2,000A MCC + feeders + lighting (sub quote, low bid)	$402,000
40a	Process interconnecting piping — stainless, beverage grade	$192,000
40b	Tie-in allowance — 8% of Div 22+23+26+40 process mechanical scope	$86,000
43a	Steam system extension	$138,000
43b	Compressed air extension + dryer upgrade	$115,000
43c	CIP skid + piping (1 circuit)	$195,000
43d	Chilled water tie-in	$78,000
41	Filling line installation — vendor-supervised; GC mechanical hookups + rigging	$248,000
Equipment	Filling line FOB — KHS firm quote	$1,625,000
DIRECT COST TOTAL		$5,278,000

Soft costs:

Item	Basis	Amount
Design/engineering	8% of direct	$422,000
Permits + testing + special inspections	—	$52,000
Contractor fee	5% of direct	$264,000
Soft cost subtotal		$738,000

Pre-contingency total: $6,016,000

Contingency — risk-based breakdown:

Risk Category	Basis	Amount
Design development	35% design; instrumentation not complete; some architectural details TBD	$175,000
Execution risk	Brownfield tie-in work; existing building conditions could differ from drawings	$210,000
Market / escalation	9-month construction window; steel and copper exposed; Q1→Q3 2026 escalation	$130,000
Total contingency		$515,000

GMP: $6,531,000 (contingency = 8.6% of pre-contingency cost)

Presented as:

GMP Proposal: $6,531,000 AACE Class 3 | Accuracy: -15% / +20% | Pricing Date: Q1 2026 Contingency: $515,000 (8.6%) | Design completion: ~35%

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The Estimate Progression — Summary

Phase	Method	Estimate	Accuracy Range
Class 5 ROM	$/SF parametric + equipment ROM	$10,130,000	$7M – $15M
Class 4 Feasibility	Equipment-factored + assembly	$7,471,000	$6M – $9.5M
Class 3 GMP Candidate	Bottom-up with sub quotes	$6,531,000	$5.5M – $7.8M

All three ranges overlap. This is correct — it confirms each estimate was calibrated appropriately and no phase made an inexplicable jump. The downward progression from Class 5 to Class 3 is normal: Class 5 included headroom for conditions that turned out to be favorable (clean site, modest utility scope, vendor quote at the low end).

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What Would Have Changed This Estimate

Higher:

• Geotech showed soft soil requiring deep foundations (+$200K–$600K)
• Hazmat found in the expansion area (+$100K–$400K abatement)
• Filling line vendor quote came in at $2.2M FOB (added $580K to GMP)
• Owner required full ammonia refrigeration instead of chilled water (+$400K)
• Winter construction schedule triggered cold-weather concrete protection (+$80K)

Lower:

• Owner self-performed controls integration (removed ~$60K from electrical scope)
• Existing electrical capacity was adequate (removed the $402K MCC and used existing panels at a $180K scope instead)
• Owner furnished and installed (OFOI) the CIP skid (removed $195K from GMP)

These scenarios are real. On a real project, you document the assumptions that could swing the estimate in each direction, put them in the BOE, and set your contingency accordingly.

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Key Lessons From This Example

1. Class 5 is always wider than it feels. The owner asked for a number on Day 1. The right answer was $10M ± a very wide range, not $10M as a commitment. Never let a Class 5 get treated as a budget.

2. The equipment quote is the most important single piece of new information. Going from ROM to a vendor budget quote reduced the estimate range more than anything else.

3. Brownfield tie-ins need their own line item. The $86,000 tie-in allowance is visible in the GMP. If it were buried in the MEP divisions, it would disappear under scope creep.

4. Contingency should be built from a list, not a %, even at Class 3. The three risk categories (design development, execution, market) are named and sized independently. When contingency is drawn down during construction, you know which bucket it’s coming from.

5. The estimate progression is a communication tool. The owner sees the estimate improve at each phase. The widening uncertainty → tightening accuracy → GMP commitment tells a coherent story about what was known when.

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Related Pages

• Estimate Classification and BOE — AACE Class 1–5 definitions and BOE structure
• BOE Template — fill-in template for the BOE accompanying this estimate
• Phase-by-Phase Workflow — the project workflow this estimate sequence follows
• Food and Beverage — F&B-specific benchmarks used in the parametric
• Parametric Estimating Models — formal parametric methods behind the Class 5 $/SF approach
• Risk Contingency and Escalation — how to build a risk-based contingency register
• Scope Misses Checklist — what to check before submitting the GMP

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