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Heavy Civil & Utility Construction

Estimating, calculations, and processes for underground utility and civil work

Software & Tools

● Blue = What we use

What We Estimate

We specialize in underground utilities and civil work. Typical scope includes:

Quantities are typically measured in linear feet, sizes/diameters, depths, and areas for surface work.

Finding Opportunities

Before estimating comes business development — finding and securing the right opportunities to bid.

Most public work is posted online. Key resources:

  • UDOT: UP3 / Bonfire for state transportation work
  • Federal: SAM.gov for government contracts
  • Military: Working relationships with HAFB and other Utah bases
  • Municipal: City/county websites, Demandstar, BidNet

Set up alerts and check regularly. Public work has defined timelines and clear bid requirements.

Most private work comes through relationships. Building a network takes time:

  • GC relationships: General contractors who need utility subs
  • Developer contacts: Residential and commercial developers
  • Engineer connections: Civil engineers who specify our type of work
  • Owner relationships: Direct relationships with municipalities, districts, private owners

Lunches, site visits, and staying in touch keep relationships warm. People work with people they trust.

An area we need to improve. Marketing efforts that help:

  • Social media: Project photos, company updates, hiring posts
  • Website: Portfolio of completed work, capabilities
  • Industry presence: AGC, trade associations, networking events
  • Reputation: Completing quality work on time — best marketing there is

Word of mouth and reputation drive most of our leads. But intentional marketing would help expand reach.

Keeping track of what's in the pipeline:

  • Bid calendar: Track due dates, pre-bid meetings, site visits
  • Lead tracking: Who called, what they need, when to follow up
  • Win/loss tracking: What we won, what we lost, and why

Organized tracking prevents missed opportunities and helps improve hit rate over time.

The Estimating Process

A streamlined 7-phase approach that moves from opportunity assessment through field handoff.

Before committing to a bid, we evaluate the opportunity and our capacity to execute. Key questions:

  • Do we have the backlog capacity to take on this work?
  • Do we have the right skillsets and manpower?
  • Is the project funded? Where is the funding coming from?
  • What's our relationship with this client?
  • Does the timeline fit with current commitments?

Relationships and trust factor heavily into bid/no-bid decisions. Funding verification is critical — it's one of the first red flags we look for. We try to bid strategically so projects don't have massive overlaps where resources compete.

Strong subcontractor relationships are essential. Building and maintaining those relationships (even simple gestures like holiday cards) matters for when we need to grow capacity.

Before diving into detailed takeoffs, we gather the information that will affect everything downstream:

  • Site conditions: Geotechnical data on big jobs, site visits and exploratory pits on smaller ones
  • Plan review: Initial review to identify scope, complexity, and potential issues
  • RFIs: Submit clarification requests early to clear up ambiguity before it becomes a problem
  • Subcontractor outreach: Reach out to subs early so quotes come back in time

Understanding what you're digging into matters — soil conditions, rock, water table, and access issues all affect production rates, equipment selection, and risk pricing. Getting this information upfront prevents rework later.

This is where the detailed measurement work happens. With site conditions understood and clarifications in hand, takeoffs are more accurate:

  • Linear feet of pipe by size and depth
  • Structure counts and types
  • Surface areas for asphalt, concrete, restoration
  • Excavation volumes accounting for actual soil conditions

Having a clear direction from the information gathering phase makes everything here more accurate and reduces rework.

With quantities in hand, we build out the full cost picture:

  • Crews & Equipment: Operations manager handles crew organization. We balance owned vs. rented equipment — often bidding at rental rates to stay covered on older equipment.
  • Production Rates: Mix of historical data, industry standards, and experience. Seasoned foremen help validate assumptions on bigger jobs.
  • Materials: Supplier quotes, material pricing
  • Subcontractor Quotes: Compile sub pricing that came back from early outreach
  • Bid Items: Organize quantities into the bid structure with units that match bid form requirements

Capturing more production data from completed jobs is an ongoing goal — the more historical data, the more accurate future estimates become.

After the bid is built, we go through it with a fine-tooth comb. This is a dedicated review session:

  • Field review: Bring in foremen or superintendents to walk through how the job will actually be installed — production rates, crew approach, equipment needs, sequencing
  • Scrutinize everything: Quantities, rates, assumptions — fresh eyes catch what tired eyes miss
  • Identify risks: What could go wrong? Soil surprises, access issues, schedule pressure
  • Set contingency: Price risk appropriately based on unknowns
  • Final margin: Make the pricing decision with full picture in view

Field staff validate what estimators assume. Their reality check on production rates and installation approach is critical — especially on larger or complex jobs.

Final push to get the bid out the door:

  • Document preparation: HCSS generates most bid forms. Proposal generator handles schedule.
  • Bonds: Coordinated with insurance provider when required
  • Submission: Submit per client requirements
  • Follow-up: Stay engaged with the client through the decision process

For smaller jobs that come in last-minute, we evaluate capacity and go after them if we can — historically we've done well on small jobs.

After award, we hold another estimating meeting to re-evaluate and make sure nothing was missed. If everything checks out:

  • Pre-preconstruction meeting with the internal team
  • Review project details, scope, production rates, equipment, crews
  • Bring the whole crew in for training if needed
  • Get suppliers and subcontractors the information they need

The goal is to set up the field team for a successful start with production from day one. A clean handoff means the field isn't inheriting estimating's assumptions without context.

Calculations

Volume Formula

Cubic Yards (CY) = Length (ft) × Width (ft) × Thickness (ft) ÷ 27

Shortcut for slabs (thickness in inches):

CY = Square Feet × Thickness (inches) ÷ 324

Quick Reference Table (CY per 1,000 SF)

Thickness CY per 1,000 SF
4"12.35
5"15.43
6"18.52
8"24.69
10"30.86
12"37.04

Concrete Strength (PSI) - What It Means

PSI = Pounds per Square Inch of compressive strength at 28 days.

PSI Rating Typical Use Mix Characteristics
2000 PSIGeneral fill, non-structural, lean concreteLow cement content, economical
2500 PSILight-duty slabs, foundations in good soilMinimum for most structural work
3000 PSISidewalks, driveways, residential slabsStandard residential/light commercial
3500 PSICommercial slabs, moderate loadsCommon commercial spec
4000 PSIStructural concrete, beams, columns, heavy slabsStandard structural specification
4500 PSIHeavy structural, pre/post-tensionedHigher cement, lower water/cement ratio
5000+ PSIHigh-performance, industrial, bridgesSpecialty mixes, additives

Concrete Ordering - Practical Notes

  • Order 5-10% extra for waste, spillage, and over-excavation
  • Specify slump (typically 4-5" for slabs, lower for structural)
  • Air entrainment required in freeze-thaw climates
  • Fiber mesh or rebar per spec - affects placement rate

Curb & Gutter (CY per 100 LF)

Type Approx. CY per 100 LF
Standard Vertical Curb (6" × 18")3.0
Rolled/Mountable Curb2.5
Integral Curb & Gutter (24" wide)4.0 - 4.5
Valley Gutter (24" wide × 6")4.5

Calculate from actual cross-section dimensions when available.

The Core Formula

Tons = Area (SF) × Thickness (inches) × Asphalt Weight (lbs/CF) ÷ 2000 ÷ 12

Hot Mix Asphalt (HMA) weighs approximately 145-150 lbs per cubic foot.

Simplified Formula (using 145 lbs/CF)

Tons = SF × Thickness (inches) × 0.0604

Even simpler (industry rule of thumb):

Tons = SF × Thickness (inches) × 0.055 to 0.06

Quick Reference Table (Tons per 1,000 SF)

Thickness Tons per 1,000 SF Notes
1"6.0Thin overlay
1.5"9.1Surface course
2"12.1Standard overlay
2.5"15.1Thicker surface
3"18.1Full-depth patch
4"24.2Heavy duty
6"36.3Base course or full-depth

Asphalt by Square Yard (SY)

1 SY = 9 SF
Tons per SY per inch ≈ 0.055

Example: 5,000 SF of 2.5" asphalt

5,000 × 2.5 × 0.06 = 750 tons (approximately)

Asphalt Removal/Milling

Same calculation - what goes in is approximately what comes out.

Removal Tons = SF × Existing Thickness (inches) × 0.055 to 0.06

Notes:

  • Milled asphalt (RAP) weighs slightly less than virgin HMA
  • Full-depth removal may require saw-cutting first
  • Haul-off weight = removal tons

Basic Excavation Volume

CY = Length (ft) × Width (ft) × Depth (ft) ÷ 27

Trench Excavation (Sloped Sides)

CY = Length × [(Top Width + Bottom Width) ÷ 2] × Depth ÷ 27

The Three States of Soil

State Definition When It Applies
Bank (In-Place)Soil in its natural, undisturbed stateMeasuring what's in the ground
LooseSoil after excavation, expandedHauling, stockpiling
CompactedSoil after placement and compactionFill, backfill, embankment

Swell Factors (Bank → Loose)

When you dig soil, it expands. This is "swell."

Material Swell Factor Loose CY per Bank CY
Sand10-15%1.10 - 1.15
Loam / Topsoil15-25%1.15 - 1.25
Common Earth20-30%1.20 - 1.30
Clay30-40%1.30 - 1.40
Rock (blasted)50-80%1.50 - 1.80

Formula:

Loose CY = Bank CY × (1 + Swell %)

Example: 100 CY bank measure of clay (35% swell)

Loose CY = 100 × 1.35 = 135 CY to haul

Shrink Factors (Loose → Compacted)

When you place and compact fill, it shrinks below loose volume.

Material Shrink Factor Compacted CY per Loose CY
Sand10-15% shrink0.85 - 0.90
Gravel10-12% shrink0.88 - 0.90
Common Earth10-15% shrink0.85 - 0.90
Clay15-20% shrink0.80 - 0.85

For ordering import material:

Loose CY Needed = Compacted CY Required ÷ (1 - Shrink %)

Example: Need 100 CY compacted fill (15% shrink)

Loose CY = 100 ÷ 0.85 = 118 CY to order

Material Weights (Tons per CY)

Material Tons/CY (Bank) Tons/CY (Loose)
Sand (dry)1.35 - 1.451.10 - 1.20
Sand (wet)1.50 - 1.701.25 - 1.40
Gravel1.40 - 1.551.15 - 1.30
Crushed Stone1.45 - 1.601.20 - 1.35
Road Base (ABC)1.50 - 1.651.25 - 1.40
Topsoil1.10 - 1.250.90 - 1.05
Clay1.50 - 1.801.15 - 1.40
Native Soil (avg)1.25 - 1.401.00 - 1.15

Import Material Calculation

How much to order:

Tons = Compacted CY Required × Weight (tons/CY) × (1 + Shrink Factor)

Example: Need 200 CY compacted road base

  • Road base: 1.55 tons/CY compacted
  • Add 15% for shrinkage
Tons = 200 × 1.55 × 1.15 = 356 tons to order

Backfill in Trenches

Volume:

Backfill CY = Trench Volume - Pipe Displacement - Bedding Volume

Pipe Displacement (CF per LF):

Pipe Diameter CF per LF
4"0.087
6"0.196
8"0.349
12"0.785
18"1.767
24"3.142

Bedding: Typically 4-6" below pipe, pipe zone to springline, and initial backfill to 12" above pipe.

Standard Trench Volume

CY = Length (LF) × Width (ft) × Depth (ft) ÷ 27

Typical Trench Widths

Pipe Size Minimum Trench Width Notes
4" - 8"24"Or pipe OD + 12"
10" - 12"30"Or pipe OD + 18"
15" - 18"36"Or pipe OD + 18"
24"+Pipe OD + 18" minPer spec requirements

Shoring Requirements (OSHA)

  • 4' depth - Evaluate for protective systems if conditions unstable
  • 5' depth - Shoring/sloping/shielding required
  • 20' depth - Engineered system required

Trench Excavation Example

Given: 500 LF of 8" water line, 5' deep, 30" wide trench

Excavation CY = 500 × 2.5 × 5 ÷ 27 = 231 CY

With 25% swell for hauling:

Loose CY = 231 × 1.25 = 289 CY

Pipe Quantities

  1. Linear Feet - Measure centerline, structure to structure
  2. Add for verticals - Risers, drops from profile
  3. Fittings - Count each (elbows, tees, reducers)
  4. Valves - Count by size and type
  5. Structures - Count manholes, vaults, boxes

Common Utility Structures

Structure Typical Depths Material
Sewer Manhole4' - 20'+Precast concrete
Water Valve BoxSurface - 6'Cast iron, concrete
Pull Box (Electrical)18" - 36"Polymer or concrete
Vault (Telecom)3' - 6'Precast or polymer
Catch Basin3' - 8'Precast concrete

Grid Layout

Total LF = (Length ÷ Spacing + 1) × Width + (Width ÷ Spacing + 1) × Length

Rebar Weights

Bar Size Diameter Weight (lbs/LF)
#33/8"0.376
#41/2"0.668
#55/8"1.043
#63/4"1.502
#77/8"2.044
#81"2.670
#91-1/8"3.400
#101-1/4"4.303

Example: 50' × 30' Slab with #4 @ 12" O.C. Each Way

Bars running 50' direction:

(30 ÷ 1 + 1) = 31 bars × 50' = 1,550 LF

Bars running 30' direction:

(50 ÷ 1 + 1) = 51 bars × 30' = 1,530 LF

Total:

3,080 LF × 0.668 lbs/LF = 2,057 lbs of #4 rebar

Area

  • 1 SY = 9 SF
  • 1 Acre = 43,560 SF

Length

  • 1 Mile = 5,280 LF
  • 1 Foot = 12 inches

Volume

  • 1 CY = 27 CF
  • 1 CY = 201.97 gallons (water)

Weight

  • 1 Ton = 2,000 lbs
  • 1 CY water = 1,685 lbs

Where These Calculations Happen

Calculation Type Primary Tool Verification
Area/Length measurementConstruction TakeoffBluebeam
Volume calculationsExcel / HCSSManual check
Material quantitiesHCSS Bid ItemsTakeoff cross-ref
Tonnage conversionsExcel formulasReference tables
Cost extensionHCSSSpreadsheet backup

Why Understand the Math?

  • Software can be wrong - Bad input = bad output
  • Sanity checking - Does this number make sense?
  • Quick estimates - Field questions, phone quotes
  • RFI responses - Understanding impact of changes

Bedding Material Quantities (CF per LF)

Pipe Size Sand Bedding (CF/LF) Crushed Stone (CF/LF) Notes
4" - 6"0.5 - 0.750.4 - 0.66" bedding depth
8" - 10"0.75 - 1.00.6 - 0.86" bedding depth
12" - 15"1.0 - 1.50.8 - 1.26" bedding depth
18" - 24"1.5 - 2.51.2 - 2.06-8" bedding depth
30"+2.5 - 4.02.0 - 3.28" bedding depth

Bedding Calculation

Bedding CY = Length (LF) × Bedding Width (ft) × Bedding Depth (ft) ÷ 27

Width: Pipe OD + 12" min | Depth: 6" below invert to springline

Barrel Volume (CY)

CY = π × (ID/2)² × Height (ft) ÷ 27

Common Manhole Sizes

Inside Diameter Wall Thickness CY per Foot Height
48"5"0.70
60"6"1.10
72"7"1.60
96"8"2.85

Riser Rings

Risers = (Total Depth - Base - Cone) ÷ 1.0 ft

Standard: 12" tall rings

Manhole Steps

Steps = (Depth - 2') ÷ 1.0 ft × 2

12" spacing, offset pattern

Frame & Cover Weights

  • Standard (24"): ~300 lbs
  • Heavy Duty (30"): ~450 lbs
  • Traffic Rated (H-20): ~600+ lbs

Gaskets per Joint

Gaskets = Number of Joints

Typically one gasket per joint

Joints per Length

Pipe Material Standard Length Joints per 100 LF
Ductile Iron18' - 20'5 - 6
PVC20'5
HDPE40' - 50'2 - 3
Concrete8'12 - 13
RCP8'12 - 13

Couplings & Restraints

  • Mechanical couplings: One per joint
  • Restraints: At bends, tees, dead ends
  • Thrust blocks: Concrete volume varies by pressure/angle

Fitting Counts

Count from plans: Elbows, tees, reducers, flanges, end caps

Water Volume for Testing

Gallons = Pipe ID (inches)² × Length (feet) × 0.0408

Add 10-20% for filling, purging, and test pressure

Testing Methods by Utility Type

Utility Type Test Method Typical Pressure Duration
WaterWater pressure test150 PSI (1.5× operating)2 hours minimum
Gas - Low PressureAir pressure test3-5 PSIG24 hours
Gas - High PressureHydrostatic (water) or air1.5× operating pressure24 hours
Gas - DistributionAir pressure test50-100 PSIG24 hours
Sewer - GravityWater infiltration testHead pressurePer spec
Sewer - Force MainWater pressure test1.5× operating2 hours
Storm DrainVisual inspection or water testN/A or head pressurePer spec

Test Volume Examples

Example 1: 1,000 LF of 8" water line

8² × 1,000 × 0.0408 = 2,611 gallons
Add 20% = 3,133 gallons total

Example 2: 500 LF of 12" sewer force main

12² × 500 × 0.0408 = 2,938 gallons
Add 15% = 3,379 gallons total

Testing Notes

  • Water: Water pressure test
  • Gas Low Pressure: Air pressure test
  • Gas High Pressure: Hydrostatic (water) or air; some utilities require hydrogen testing
  • Sewer Gravity: Water infiltration test
  • Sewer Force Main: Water pressure test
  • Storm: Visual inspection or water test

Excavator Production (CY per Hour)

Ideal conditions, 50-minute hour

Excavator Size Loose CY/Hour Bank CY/Hour Notes
Mini (1-3 CY)15 - 2512 - 20Tight spaces, shallow
Small (3-5 CY)40 - 6032 - 48Standard utility work
Medium (5-8 CY)80 - 12064 - 96Deep trenches, large pipe
Large (8-12 CY)150 - 220120 - 176Mass excavation

Pipe Installation Rates (LF per Day)

Pipe Size LF/Day (Crew of 3-4) Factors
4" - 6"200 - 400Small, fast handling
8" - 12"150 - 300Standard utility size
15" - 18"100 - 200Heavier, slower
24" - 30"50 - 100Requires larger equipment
36"+25 - 75Heavy equipment, careful placement

Compaction Rates

Equipment SF/Hour CY/Hour
Plate Compactor200 - 400N/A
Jumping Jack100 - 200N/A
Vibratory Roller1,000 - 2,00050 - 100
Sheepsfoot Roller800 - 1,50040 - 75

Backfill Placement Rates

  • Hand placement: 10-20 CY/day per person
  • Equipment placement: 50-100 CY/day
  • Mass fill: 200-400 CY/day with loader

Rates vary by soil conditions, depth, access, weather, and crew experience. Use historical data when available.

Truck Capacities

Truck Type Loose CY Capacity Tons Capacity Notes
Single Axle8 - 1210 - 15Small jobs, tight access
Tandem Axle12 - 1815 - 22Standard dump truck
Tri-Axle18 - 2222 - 28Larger loads
End Dump (Semi)20 - 2525 - 30Mass hauling
Bottom Dump25 - 3030 - 35Spreading applications

Haul Cycle Time

Cycle Time = Load Time + Haul Time + Dump Time + Return Time

Typical Times

  • Load: 3-5 minutes
  • Dump: 1-2 minutes
  • Haul/Return: Varies by distance

Trucks Needed

Trucks = (Production Rate CY/Hour × Haul Time Hours) ÷ Truck Capacity CY

Example: Excavating 100 CY/hour, 30-minute round trip, 18 CY trucks

Trucks = (100 × 0.5) ÷ 18 = 2.8 trucks (round up to 3)

Temporary vs Permanent

  • Temporary: Cold mix, base only (50-75% of permanent cost)
  • Permanent: Hot mix, full depth (match existing)

Asphalt Patching

SF = Trench Width (ft) × Length (ft) + Overlay

Overlay: Extend 6-12" beyond trench edges

Thickness: Surface 1.5-2", Base 2-4" (if needed), or match existing

Concrete Patching

For concrete surfaces:

CY = SF × Thickness (inches) ÷ 324

Sod & Seed

For grass areas:

  • Sod: Measure SF, add 5% waste
  • Seed: Typically 2-4 lbs per 1,000 SF
  • Topsoil: 2-4" depth, calculate CY

Restoration Width

Trench Width Typical Restoration Width
24" - 30"36" - 48"
36" - 48"48" - 60"
60"+Trench width + 12" each side

Water Volume Calculation

Gallons = Area (SF) × Depth (ft) × 7.48

Pump Sizing

GPM needed based on water table and infiltration:

Application Typical GPM Pump Size
Small trench (4-8" pipe)10 - 302" - 3" pump
Medium trench (12-18" pipe)30 - 753" - 4" pump
Large trench (24"+ pipe)75 - 1504" - 6" pump
Manhole/vault excavation20 - 503" - 4" pump
Mass excavation100 - 300+Multiple pumps

Well Point Systems

For deeper excavations or high water tables:

  • Spacing: Typically 3-6 feet apart
  • Depth: 5-10 feet below excavation bottom
  • Header: Connect multiple well points to pump

Dewatering Duration

Required during excavation, pipe installation, and backfill (if water table high)

Lane Closure Linear Feet

LF = Work Length + Taper Length + Buffer

Taper Lengths (MUTCD)

Speed Limit Taper Length
25 mph100'
35 mph150'
45 mph200'
55 mph300'

Signage Quantities (Per Lane Closure)

  • Advance warning: 2-3 signs
  • Work zone: 2-4 signs
  • End work zone: 1 sign
  • Barricades: 1 per 10-20 LF
  • Cones: 1 per 10-15 LF (taper), 1 per 20-30 LF (work zone)

Flagging Hours

  • Setup/takedown: 1-2 hours each
  • During work: Continuous coverage
  • Peak hours: May require additional flaggers

Traffic Control Plan

Required for work in roadway, lane closures, sidewalk closures, intersection work

Rock Classification

Type Description Method
RiprapLoose rock, can be rippedRipper attachment
Soft RockCan be excavated with hoe ramHoe ram, breaker
Hard RockRequires drilling/blastingDrill & blast

Ripping Production

  • Riprap: 50-100 CY/hour
  • Soft rock: 20-50 CY/hour
  • Hard rock: Not rippable, requires blasting

Hoe Ram/Breaker Production

  • Soft rock: 10-30 CY/hour
  • Medium rock: 5-15 CY/hour
  • Hard rock: 2-8 CY/hour

Drilling & Blasting

  • Drill holes: 3-4" diameter, 3-5 feet deep
  • Hole spacing: 3-5 feet apart
  • Blast pattern: Per blasting contractor
  • Production: Varies by rock type

Requires specialty subcontractors and permits. Rates vary by rock type, depth, and access.

Material Formula Notes
ConcreteCY = SF × inches ÷ 324Add 5-10% waste
AsphaltTons = SF × inches × 0.055Standard HMA
ExcavationCY = L × W × D ÷ 27Bank measure
Import fillTons = CY × 1.5 × 1.15Avg weight + shrink
BackfillCY = Trench - Pipe - BeddingAdd compaction factor

Lessons Learned

Don't cut corners. Estimating is scrupulous, highly detailed work with a lot of moving parts. Data needs to be captured accurately, analyzed, cross-referenced, and checked. Cutting corners always comes back to bite you. You can't wing it.

Team

Andrew and I lead the estimating efforts, with support from project managers, superintendents, and our operations manager as needed. The goal is to grow this process — better data capture, stronger subcontractor relationships, and more involvement from field leadership on larger bids.