The Definitive Electrical Estimating Glossary

Electrical estimating involves specialized terminology, codes and technical concepts that every estimator needs to master. From understanding circuit types to navigating NEC requirements, this glossary covers the essential terms you'll encounter when estimating electrical projects.

This guide includes both electrical-specific technical terms and general estimating terminology used throughout the bidding and project execution process.

A

Addendum — A document issued during the bidding period that modifies or clarifies the original plans and specifications. All estimators must acknowledge and incorporate addenda into their bids, affecting scope and pricing.

Allowance — A specified dollar amount included in an estimate for materials or equipment not yet selected. Common for light fixtures and specialty devices, allowing the owner to make selections later while keeping the bid complete.

Area Takeoff — Measuring spaces or zones on plans to calculate lighting requirements, conduit fill for large areas, or square-footage-based estimates.

As-Built Drawings — Final drawings that reflect all changes made during construction. May be required deliverables affecting project scope and cost.

Assembly — A grouping of related materials and labor into a single estimating unit. Examples include complete receptacle installations with device, box, wire and labor, improving estimating speed and accuracy.

Assembly Database — Pre-built combinations of related materials and labor stored in estimating software for quick pricing of common installations.

Auto-Count — A software feature that automatically identifies and counts electrical devices, fixtures, and components from digital plans using symbol recognition, significantly reducing manual takeoff time and human error.

Auto Home Run — An estimating software function that automatically traces and measures circuit home run paths from devices back to panel boards, calculating wire lengths and conduit runs without manual measurement.

B

Bid — A formal proposal submitted by a contractor offering to perform work for a specified price. Electrical estimates become bids when submitted to general contractors or owners.

Bid Comparison — The process of analyzing multiple supplier quotes side-by-side to determine best pricing for materials and equipment.

Bid Day — The deadline for submitting bids on a project. Estimators often receive last-minute quotes from suppliers and subcontractors, requiring quick analysis and bid compilation.

C

Change Order — A written modification to the contract, changing scope, price or schedule. Estimators must price change orders using similar methods as original estimates, often with premium pricing for disruption.

Change Order Tracking — Software functionality that documents scope changes, tracks additional costs, and manages change order pricing throughout a project.

Circuit – A complete path for current to flow, including wiring, protective devices, and connected loads. Estimators calculate circuit lengths and wire sizes to determine labor and material costs.

Collaborative Estimating — Multiple estimators working simultaneously on different portions of a large estimate using networked or cloud-based software.

Conditional Formatting — Software features that highlight or color-code items based on criteria (incomplete pricing, missing labor, high-cost items) for quality control.

Conduit – A protective tubing system for electrical conductors (PVC, EMT, RMC, FMC, etc.). Estimated by linear foot, with separate fittings and supports.

Contingency — A percentage or dollar amount added to an estimate to cover unforeseen conditions or minor scope changes. Typically 3-10% depending on project complexity and risk.

Crew Size — The number of workers assigned to a task, affecting productivity rates and labor costs. Standard electrical crews are often journeyman/apprentice pairs.

Cut Sheet — A manufacturer's product specification page showing dimensions, features and technical data. Essential for verifying that estimated materials meet specification requirements.

D

Database Pricing — A stored collection of material costs, labor rates, and productivity factors that automatically populate estimates when items are selected or counted.

Digital Takeoff — The process of performing quantity measurements directly from electronic PDF or CAD drawings using specialized software, replacing manual scaling and counting methods.

Direct Costs — Expenses directly attributable to a specific project, including material, labor and equipment. Distinguished from indirect costs (overhead) in estimate breakdowns.

E

Electrical Estimating Software — Specialized programs designed for electrical contractors to perform takeoffs, pricing, and bid preparation (examples include Accubid, ConEst, Trimble Autobid, McCormick Systems).

Equipment Grounding Conductor (EGC) – A wire providing a path to ground for fault current; size impacts material cost.

Escalation — The projected increase in material or labor costs over time. Important for projects with long schedules or delayed starts, typically expressed as an annual percentage.

Estimate Template — A pre-formatted estimate structure with standard line items, assemblies and formulas that can be reused for similar project types.

H

Historical Data — Records of actual costs from previous projects used to improve estimating accuracy. Valuable for validating production rates and unit costs.

I

Indirect Costs — Overhead expenses not directly tied to a specific project, including office rent, utilities, insurance and administrative salaries. Applied to estimates as a percentage markup.

J

Job Costing — The process of tracking actual costs during construction and comparing them to estimated costs, providing feedback for improving future estimates.

L

Labor Burden — Additional costs beyond base wages, including payroll taxes, workers' compensation insurance, benefits and paid time off. Typically adds 35-60% to base labor rates.

Labor Unit — The amount of work time required to install a specific item, typically expressed in man-hours per unit. The foundation of labor cost estimating, varying by installation conditions and crew skill.

Layer Control — The ability to toggle visibility of different drawing layers (electrical, architectural, structural) in digital plans to isolate relevant information for takeoff.

Lead Time — The duration between ordering materials and delivery. Long lead items like switchgear, transformers or custom panels must be identified early to avoid schedule delays.

Line Item — A single entry in an estimate representing a specific material, labor task or assembly. Detailed estimates may contain hundreds of line items for accurate cost tracking.

Load Calculation – The process of determining electrical demand (in amperes or kVA) to size conductors, transformers, and overcurrent protection.

Lump Sum — A single fixed price for a complete scope of work, rather than itemized unit prices. Requires a comprehensive understanding of all included work.

M

Markup — A percentage added to costs to cover overhead and profit. Typical markups range from 10-30% depending on company structure, project risk and market conditions.

Material List — A comprehensive listing of all materials required for a project with quantities, descriptions and pricing. Generated from the takeoff process.

O

On-Screen Takeoff — Software that allows estimators to measure, count, and mark up digital drawings directly on a computer screen, with automatic calculation of quantities and lengths.

P

Point-to-Point Measurement — A takeoff method where the estimator clicks sequential points on a digital drawing to measure conduit runs, wire pulls, or cable tray lengths.

Production Rate — The speed at which work is completed, typically expressed as units per hour or hours per unit. Accurate production rates are essential for competitive labor pricing.

Productivity Factor — A multiplier applied to standard labor units to account for job-specific conditions (difficult access, height work, congested areas) that affect installation speed.

Profit — The amount added to an estimate above all costs and overhead, representing the contractor's compensation for risk and business operation. Typically 5-15% of the total cost.

Proposal — A formal document submitted to a potential client outlining scope, price and terms for performing work. The final product of the estimating process.

Q

Quantity Takeoff — The process of measuring and counting all materials required from the construction documents. The foundation of accurate estimating, typically performed from plans and specifications.

Quote — A price provided by a supplier or subcontractor for specific materials or services. Estimators collect and compare quotes to determine best pricing for estimates.

R

Report Generation — Automated creation of material lists, labor summaries, and cost breakdowns from the estimate database for proposals and internal tracking.

S

Scale — The ratio between drawing dimensions and actual dimensions, such as 1/4" = 1'-0". Essential for accurate measurement during takeoffs.

Scope of Work — A detailed description of all work included in an estimate or contract. Clear scope definition prevents disputes and ensures accurate pricing.

Specification — Written requirements describing materials, equipment and installation methods for a project. Must be carefully reviewed as they often supersede drawing details and affect material selection.

Submittal — Documentation provided to the design team for approval before purchasing materials or equipment. Processing time affects project schedule and must be considered in planning.

Supply House — A wholesale distributor of electrical materials and equipment. Estimators maintain relationships with supply houses to obtain competitive pricing and product availability information.

Symbol Library — A database of electrical symbols within estimating software that enables automatic device recognition and counting from plan sheets.

U

Unit Price — The cost for a single unit of work, such as per linear foot of conduit or per device installed. Used in quantity-based estimating and change order pricing.

Utility Coordination — The process of working with electric utilities for service connections. May require scheduling, deposits and utility company charges included in estimates.

V

Value Engineering — The process of identifying alternative materials or methods that reduce cost while maintaining functionality. Often performed after initial estimates to meet budget targets.

Voltage Drop – The reduction in voltage due to wire resistance, affecting conductor sizing and efficiency.

W

Waste Factor — Additional material quantity added to account for cutting waste, damage and errors. Typical waste factors range from 5-15% depending on material type and installation complexity.

Work Breakdown Structure (WBS) – A hierarchical organization of estimate components for tracking and reporting.

Understanding these terms will help electrical estimators communicate effectively, interpret plans accurately and produce detailed, competitive bids. For more information on electrical estimating software and tools, visit McCormick Systems.