AACE CEP Certified Estimating Professional key terms

The documented set of assumptions, scope description, methods, data sources, and qualifications that explain how an estimate was built and what it does and does not include. It lets reviewers and users interpret the number correctly.

A category describing how mature an estimate is, based on the degree of project definition and the expected accuracy range. Classes progress from conceptual through definitive as design information increases.

The expected low-to-high spread of possible actual cost around an estimate, reflecting uncertainty at a given stage of project definition. It is usually expressed as a percentage below and above the point estimate.

An amount added to an estimate to cover costs that are likely to occur but cannot be specifically identified at the time of estimating, based on historical experience and assessed risk. It excludes scope changes and major unforeseen events.

Funds held outside the project budget by senior management for unanticipated in-scope work or unknown-unknown events. It is released only through formal change control and is not part of the estimator's contingency.

The provision in an estimate for expected increases in the cost of labor, materials, or services between the estimate base date and the time the work will actually be performed.

The reference date to which all costs in an estimate are normalized, so that pricing from different periods can be combined consistently and escalation can be calculated to the execution period.

A quantified provision in an estimate for a known cost element that cannot yet be priced precisely, such as an allowance for field office costs or freight. It differs from contingency in that the item is identifiable.

The degree to which project requirements, deliverables, and boundaries are described in enough detail to support estimating. Better scope definition generally narrows the accuracy range of an estimate.

A hierarchical decomposition of project scope into manageable deliverable-oriented elements. Estimating is typically organized along WBS levels so costs can be summed, checked for completeness, and compared across projects.

A standardized numbering structure used to classify and aggregate estimate line items by WBS element, cost type, or resource category, enabling consistent roll-ups, benchmarking, and reporting across projects.

An organized framework that sorts estimated costs by categories such as labor, materials, equipment, subcontracts, and indirects, so the estimate can be analyzed, checked, and converted into a project budget.

A cost that can be attributed specifically and unambiguously to a project deliverable or work item, such as installed pipe, structural steel, or dedicated craft labor. Direct costs form the core of most estimates.

A cost incurred for the benefit of the overall project or organization that cannot be traced directly to a single work item, such as site supervision, temporary facilities, insurance, or home office support.

Ongoing business costs of running an organization, such as administration, rent, and management salaries, that are not chargeable to a specific project deliverable. It is recovered through markups or rates applied to direct costs.

An amount added to estimated cost to cover items such as overhead, profit, financing, and taxes when arriving at a selling price. Markup is expressed as a lump sum, a percentage, or a rate.

The return earned by a contractor above its costs and overhead for performing the work. In estimating for bids it is a management decision, while in cost analysis of a proposal it is examined separately from cost.

The review of the individual elements that make up a proposed price, such as labor hours, wage rates, material quantities, and productivity, to judge whether each element is reasonable and well supported.

The examination of a proposed price as a whole, compared against other offers, historical prices, published catalogs, or independent estimates, without breaking the price into its component costs.

An independent estimate of what a product or service ought to cost, developed from the buyer's perspective using its own data and productivity assumptions, to benchmark a supplier's proposed price during negotiation.

A method that builds a total cost by estimating individual work packages or line items in detail and summing them, often using quantities multiplied by unit rates. It is the most detailed and generally most accurate approach.

A method that develops a total cost from limited project information, using analogies, capacity factors, or parametric relationships, and then allocates that total to lower-level elements. It suits early, low-definition stages.

A technique that derives a new estimate by adjusting the known cost of a similar, completed project for differences in size, scope, location, and time. It relies on the quality of the historical analogy.

A technique that uses statistical relationships between a measurable driver, such as capacity or floor area, and cost, derived from historical data, to compute an estimate. Its reliability depends on the validity of the underlying model.

A mathematical formula or model that expresses cost as a function of one or more project parameters, such as capacity, weight, or throughput, derived from historical data. It underpins parametric estimating.

A method that estimates a portion of project cost as a ratio or percentage of a known primary cost, such as estimating piping cost as a factor of equipment cost. Factors come from historical project data.

An exponent used in the exponential scaling formula to adjust the cost of a facility for a change in capacity, reflecting economies of scale. Values typically fall below one, so cost rises less than proportionally.

The systematic measurement of materials and work items from design drawings, specifications, and models to produce the quantities that are multiplied by unit rates in a detailed estimate.

The cost per unit of measure for a work item, such as cost per cubic meter of concrete or per meter of pipe, combining material, labor, and equipment components. Quantities multiplied by unit rates give line-item cost.

The rate at which labor produces installed work, usually expressed as work hours per unit of output. It is affected by conditions such as site access, weather, supervision, and craft skill, and drives labor-hour estimates.

The cost per hour of craft or staff labor, including base wage plus burdens such as payroll taxes, insurance, and benefits. It is applied to estimated labor hours to derive labor cost.

The single most likely value produced by an estimating method before any range or probabilistic treatment is applied. It is the number to which contingency and escalation provisions are typically added.

A structured log of identified project risks, each with its assessed probability, potential cost or schedule impact, and planned response. It provides the basis for quantifying contingency in a risk-based estimate.

The process of identifying, assessing, and quantifying uncertainties that could affect project cost or schedule, often through qualitative scoring or probabilistic modeling, so their potential effects can be reflected in the estimate.

A probabilistic technique that repeatedly samples input distributions for uncertain cost elements to produce a distribution of total project cost. It supports setting contingency at a chosen confidence level.

The formal process by which modifications to scope, schedule, or budget are proposed, evaluated, approved or rejected, and recorded. It protects the integrity of the approved estimate and budget baseline.

The review of an estimate for completeness, mathematical correctness, appropriate methodology, and reasonableness of rates and quantities, often by comparing results against benchmarks or independent checks before approval.

The practice of comparing an estimate's cost metrics, such as cost per unit of capacity or hours per unit of output, against historical or industry reference data to test reasonableness and identify outliers.

A contract provision that adjusts the contract price for changes in specified cost indices, such as labor or steel prices, over the performance period. Estimators must account for such clauses when pricing work.