Construction Estimating Glossary

What is a takeoff, and how is it different from an estimate?

A takeoff is the measured quantity of work. An estimate is that takeoff priced. The two halves fail for different reasons and get checked differently, so keep them separate.

Takeoff. Every work item measured off the drawings and specifications, organized by item and unit of measure, with no pricing attached. A takeoff is auditable — two competent estimators measuring the same slab should land close to each other, and any difference should be traceable to a stated measurement or interpretation choice rather than to judgment about price. The pricing that follows is judgment, and two competent estimators will not agree on it. When a number looks wrong, establish which half produced it before arguing about the total.

Quantity takeoff vs material takeoff. A quantity takeoff measures all work, including items that consume only labor: layout, stripping formwork, patching, testing. A material takeoff lists only what gets purchased, in purchase units, with waste added — sheets rather than square feet, stock lengths rather than linear feet. Ordering from a quantity takeoff under-buys. Estimating labor from a material takeoff misses the labor-only work entirely.

SFCA. Square feet of contact area: the surface of formwork touching the concrete, counted per face. A wall 100 feet long and 8 feet tall, formed both sides, is 1,600 SFCA. For vertical and elevated work — walls, columns, beams and suspended slabs — formwork labor and materials usually cost more than the concrete they shape. Slabs on grade are the exception: forming is perimeter edge form only, and the cost sits in finishing area, reinforcing, vapor barrier and curing instead. Either way, a cast-in-place estimate priced by cubic yard alone is not an estimate. One concrete assembly carries at least four units: cubic yards of concrete, SFCA of form, weight of reinforcing, square feet of finish.

Waste factor. A percentage added to the net measured quantity for cutting loss, breakage, spillage, coverage variance and over-ordering. The percentage is applied to material quantities, not to labor hours. That does not mean waste is labor-free — over-poured concrete still gets placed and finished, and a cut-up layout burns hours in cutting and handling. Carry that labor in the production rate or the productivity factor, so it is priced once and visibly, rather than adding the waste percentage to hours as well. It should vary by item and geometry — a rectangular floor and a cut-up floor of equal area do not waste the same — and one blanket percentage across a whole takeoff is worth questioning, because it usually cannot be defended item by item when someone asks. Waste is a known, quantifiable loss, not contingency; stacking both to feel safe double-counts.

How do estimators price labor?

Material quantities come off the drawings. Labor hours do not — they come from a production rate, adjusted for conditions on this particular job.

Productivity factor. A multiplier applied to base labor hours for the conditions a standard production rate assumes away: trade stacking and congestion, restricted access, working over occupied space, height, weather, overtime fatigue, broken quantities, and the learning curve on an unfamiliar detail. In the convention used here the factor multiplies base hours, so a value above 1.0 means more hours. Other estimators use the inverse — a factor below 1.0 signalling reduced output — so state on the estimate which convention the number follows. This is where the estimator's judgment about a specific job lives, and it is the easiest place in an estimate to bury a number nobody can defend. Every factor should carry a written reason.

Crew day. One day of work by a named crew composition — a foreman, three journeymen, an operator and a machine — used where output per unit is hard to measure. Demolition, sitework, hoisting and punch list are commonly priced this way. Cost equals wages plus burden times hours, plus the equipment on the crew. Crew-day pricing does not remove the productivity question; it relocates it into "how many days", which still needs a basis.

Labor burden. Everything added to the base wage to reach the real hourly cost of an employee: payroll taxes, unemployment insurance, workers' compensation, fringe or union benefits, vacation and holiday, per diem and travel. General liability is usually rated against contract value or gross receipts rather than payroll, so it normally sits as its own line or in markup, not in labor burden — wherever you put it, put it in one place only. Burden is part of the cost of labor, not markup and not overhead. Treating it as a markup either double-counts it against subcontracted work or leaves it out of self-performed work.

General conditions vs general requirements: what is the difference?

These get used interchangeably and mean different things. One is a specification. One is a cost. And one of them has two meanings on its own.

General requirements. CSI MasterFormat Division 01. A specification division stating what the contractor must do beyond installing permanent work: submittals, schedules, mockups, quality control and testing, temporary facilities and controls, safety, cleaning, closeout documentation, O&M manuals and warranties. Reading Division 01 is how you find out what the general conditions are going to cost.

General conditions (the contract document). The boilerplate legal terms of the agreement — rights, duties, payment, claims, termination. The AIA A201 general conditions document is the familiar example. When a lawyer says general conditions, this is usually what is meant.

General conditions (the cost category). Project-specific indirect costs of running the job that cannot be charged to a single trade: superintendent and project management time, trailer and jobsite office, temporary power, water, heat and light, dumpsters and cleanup, sanitary facilities, safety supplies, small tools and consumables, layout and survey, protection, and permits where the contractor carries them.

Where the line moves, and why duration matters. There is no universal boundary between general conditions and overhead. Home office cost normally sits in markup and jobsite indirect cost sits in general conditions, but firms move items — especially supervision — across that line. Compare two bids without asking which side each item sits on and you are not comparing the same thing. General conditions also scale with schedule rather than contract value: a superintendent, a trailer and temporary power cost the same per week whether crews put a lot or a little work in place. Not every general conditions item behaves this way — debris removal, cleanup and hoisting scale with the volume and phase of work rather than the calendar, so price those against the anticipated pulls or lifts and carry only the genuinely time-driven items on a weekly rate.. Any general conditions number quoted without a stated duration is incomplete.

Allowance, contingency, escalation: which one covers what?

Three line items, three different jobs. Confusing them is how an estimate ends up carrying the same risk twice, or none of it.

Allowance. A stated dollar amount carried in the contract sum for scope defined in kind but not in selection — door hardware, light fixtures, appliances, finish flooring. The work is in the contract; the choice is not made. Under standard form contracts, actual cost is reconciled against the allowance and the contract sum adjusts by change order in either direction — but custom agreements often limit that adjustment, so read the allowance clause rather than assuming it. The dispute is rarely about the amount. It is about what the allowance covers: material only, or material plus installation, taxes, handling and markup. The allowance clause decides that, and when it is silent, someone eats the difference.

Contingency. Money for known unknowns inside the defined scope: design development between the current set and complete construction documents, minor quantity growth, ordinary field conditions. It is not for scope the owner adds later, which is a change order, and not for price movement over time, which is escalation. Owner's contingency sits in the owner's budget; contractor's contingency sits inside the bid against the contractor's own risk. A contingency with no stated basis is padding. The defensible basis is document completeness — a schematic-level estimate should carry more than one priced from a finished set, and the estimate should say which it is.

Escalation. An allowance for price movement between the date the estimate was priced and the date material is bought or labor performed. It is a function of time and market, not risk, so it belongs per commodity and per period rather than as one blanket percentage — steel, copper, gypsum, lumber and fuel do not move together or on the same cycle. Escalation means nothing without two dates: the pricing basis date the estimate is valid as of, and the construction midpoint it is escalated to. An estimate with no pricing date cannot tell you how much of its escalation is already spent.

Markup, margin and O&P

Markup is arithmetic on cost. Margin is arithmetic on price. The difference is where contractors lose money quietly and repeatedly.

Markup vs margin. Markup is the percentage added to cost to reach price. Margin is the percentage of the price that is not cost. Add 20 percent markup to $100 of cost and the price is $120, which is a margin of 16.7 percent. Keeping 20 percent of the price requires a 25 percent markup. Bidding to a margin target using a markup number is a small, guaranteed shortfall on every job.

O&P. Overhead and profit: the markup covering home office overhead that cannot be charged to a job, plus profit. The familiar "ten and ten" shorthand is a convention, seen most often in insurance restoration, and applied in sequence it compounds to 21 percent on cost rather than 20. It is not a market rate. The overhead percentage a company needs is its annual overhead divided by the volume it expects to recover from; the profit percentage should reflect the risk on this job.

Markup on markup. A subcontractor's price already contains that subcontractor's overhead and profit. General contractor O&P applied on top is a markup on a markup. That is normal and defensible, because the GC carries real cost and real risk on subcontracted work — but it should be visible in the estimate rather than blended into one number. An owner who finds it late treats it as something that was hidden.

How is the price structured? Lump sum, unit price, GMP

These describe how the price is built and who carries which risk. They are not interchangeable, and a single project often uses more than one.

What do leveling and scope gap mean when comparing bids?

Two terms describing the same problem from opposite ends: bids are not comparable as submitted.

Scope gap. Work that appears in nobody's bid because every bidder assumed it belonged to someone else. It lives at trade boundaries — blocking and backing, flashing, sealants, firestopping, final connections to owner-furnished equipment, hoisting, patching after demolition, temporary protection, testing and balancing — and at the seams between bid packages. To find it, line the bidders' exclusions up against each other. Anything excluded by every bidder should be treated as a gap until you can point to the package, the owner or the GC that actually carries it — otherwise it is in your budget whether you priced it or not.

Bid leveling. Normalizing bids so they can be compared: add back to each bid the scope it excluded, subtract scope it carried beyond the package, resolve alternates, unit prices and allowances to one basis, then compare adjusted totals rather than submitted totals. The output of leveling is a new number for each bidder. The submitted low bid and the leveled low bid can be different bidders — that is the reason for doing it, and a leveling sheet that never changes the order is worth a second look, because it either confirms an unusually clean bid package or shows the adjustments were never made.

Is value engineering the same as cutting cost?

Value engineering, as a discipline, is a function analysis method: define the function an element must perform, price alternative ways to perform that same function, and select the lowest total cost that maintains the function and the life-cycle performance. The test is function retained at lower cost.

What usually gets called VE on a job is cost reduction — substitute a cheaper product, reduce a quantity, delete a scope, lower a specification. Some of that is legitimate, and an over-specified assembly that performs identically for less is a real find. Much of it is descoping, and the label moves the conversation away from what is being given up.

The usable distinction: a real VE item states the function it preserves and the effect over the life of the building, not only the first-cost delta. If an item cannot say what stays the same, it is a scope reduction and should be presented to the owner as one. That wording matters later, because a VE log gets read during disputes.

What should a finished estimate label explicitly?

Every term above should be visible on the document you receive, whether your own estimator produced it or an outside service did. If the file does not show these, you cannot check the number.

• A pricing basis date, so escalation can be measured from somewhere
• Unit of measure on every line, with quantity shown separately from price
• Which markups sit inside a unit price and which are applied at the summary
• Waste factors per item, not one blanket percentage across the takeoff
• Productivity factors with the condition justifying each one written beside it
• General conditions itemized and tied to a stated project duration
• Allowances listed with what each covers: material, installation, taxes, markup
• Contingency with a stated basis, normally the completeness of the documents priced
• A labor, material, equipment and subcontract split, so self-performed work can be checked against your own production history and subcontracted work cannot hide inside it", "Bond, insurance and sales tax shown as their own lines, with the basis stated, rather than buried in the markup
• An inclusions and exclusions page — the exclusions are the more useful half

Which definition wins when your contract disagrees with this page?

Everything above is conventional usage, and conventional usage loses to a contract. If your subcontract defines general conditions as a fixed percentage, writes an allowance to exclude installation, or states that unused GMP contingency reverts to the owner, that governs your job. Read the definitions article, the general conditions document and Division 01 before assuming the industry meaning applies.

Regional and sector variation is real. Some markets fold supervision into overhead; others carry it in general conditions. Public work, insurance restoration and private negotiated work treat O&P differently. Heavy civil leans on unit prices where building work leans on lump sum. None of that makes one usage wrong, which is exactly why stating your own definitions on your own estimate is worth the ten minutes.

One last thing worth saying plainly: knowing these terms is not a reason to outsource anything. If you self-perform a trade and bid similar assemblies week after week, your own historical unit costs and your crew's production rates are usually the better source — provided the history is recent, consistently coded and drawn from comparable work — because they reflect your crews rather than a national average. Outsourced takeoff and estimating earns its place most clearly in two situations — when bid volume runs past what your estimator can cover, and when a job pulls you into a trade or building type you do not price often. Outside of those, what it buys is capacity, not correctness.