Construction Terminology Glossary: The Words You'll Actually Hear on a Canadian Jobsite

Ask two estimators from different firms what "allowance" means and you'll sometimes get two different, if overlapping, answers. Construction terminology isn't standardized the way a lot of people assume, and a term that means one specific thing on a commercial project can get used more loosely on a residential job down the street. This glossary organizes the terms that actually show up day to day, grouped by what you're doing when you need them.

Drawing & Documentation Terms

The vocabulary that shows up on the drawing set itself and the documents that travel with it.

Working Drawings

The full set of architectural, structural, mechanical, electrical, and civil drawings issued for construction or pricing. Also called the "drawing set" or "plan set."

Specifications (Specs)

The written document that accompanies the drawings, describing material quality, installation methods, and standards the drawings alone don't capture. Specs often override what a drawing visually implies.

Reflected Ceiling Plan (RCP)

A plan view showing the ceiling as if reflected in a mirror on the floor below, used for lighting, ceiling grid, and HVAC diffuser layout.

Revision Cloud

A cloud-shaped line drawn around a section of a drawing that's changed since the last issue, paired with a revision number or letter referencing the change log.

As-Built Drawings

Drawings updated after construction to reflect what was actually built, which sometimes differs from the original design due to field changes.

Detail Callout

A reference on a plan view pointing to a more zoomed-in drawing elsewhere in the set, showing exactly how a specific connection or condition is built. Missing a detail callout is one of the more common ways a takeoff misses scope.

Addendum

A formal written change or clarification issued to the bid documents before contracts are signed, becoming part of the official contract documents once issued. Different from a change order, which happens after work starts.

Request for Information (RFI)

A formal question submitted by a contractor to the design team when a drawing or spec is unclear, ambiguous, or appears to conflict with another document, along with the design team's written answer.

Confused about how these pieces fit together on your first read-through? Our guide on understanding construction drawings walks through reading a full set in order.

Takeoff & Measurement Terms

The vocabulary specific to counting and quantifying what's on the drawings.

Quantity Takeoff (QTO)

The process of counting and measuring every material and item shown on a drawing set, without attaching cost. Sometimes called a material takeoff or quantity survey.

Bill of Quantities (BOQ)

A formatted, itemized document listing every measured quantity from a takeoff, organized by trade or CSI division, typically used for tendering larger projects.

Waste Factor

A percentage added on top of a raw material quantity to account for cuts, breakage, and offcuts. It varies by material, drywall and tile typically run higher than a simple concrete pour.

Board Foot

A volume-based unit for pricing lumber, one foot long, one foot wide, one inch thick, distinct from square footage.

Linear Foot

A measurement of length only, used for materials sold by length rather than area, like baseboard, fencing, or eavestrough.

EQ (Equal)

An abbreviation on a drawing indicating that spaces or dimensions should be divided equally, without specifying an exact number, common on layouts where symmetrical spacing matters more than a fixed measurement.

Takeoff Sheet

The working document, paper or digital, where measured quantities get recorded during a takeoff, typically organized by item, unit of measure, and running quantity as counting proceeds through the drawing set.

Scale

The ratio between a drawing's measurements and the actual building's real dimensions, stated in the title block, either as an imperial ratio (1/4" = 1'-0") or a metric ratio (1:50), and required knowledge before measuring anything by hand off a paper drawing.

Gross Floor Area vs. Net Floor Area

Gross floor area includes everything within a building's exterior walls, structure, mechanical rooms, corridors. Net floor area excludes those and measures only usable occupied space, a distinction that changes cost-per-square-foot comparisons significantly if the two get mixed up.

Our full walkthrough on running a first quantity takeoff puts several of these terms into an actual counting workflow.

Cost & Pricing Terms

Where a takeoff's raw numbers turn into dollars, and where terminology confusion gets expensive.

Markup

A percentage added on top of cost to reach a selling price. A $1,000 cost marked up 20 percent prices at $1,200.

Margin

The percentage of the selling price that represents profit, calculated differently than markup and producing a lower number from the same underlying figures.

Allowance

A pre-set budget amount for a specific item not yet finalized at the time of contract, like flooring or fixtures the owner hasn't selected. Spent on that specific item, not treated as general reserve.

Contingency

A general reserve amount set aside for unforeseen costs across the whole project, distinct from an allowance because it isn't earmarked for any specific item.

Unit Price

A cost expressed per unit of measure (per square foot, per cubic yard, per linear foot) rather than as a lump sum, used to price individual line items on an estimate.

Lump Sum

A single fixed price covering an entire scope of work, as opposed to unit pricing broken out by individual item.

Soft Costs

Project costs not directly tied to physical construction, permits, design fees, financing costs, and insurance, as distinct from hard costs (materials and labour).

Direct Cost vs. Indirect Cost

Direct costs are tied to a specific item of work, the concrete, the labour pouring it. Indirect costs support the project generally without being tied to one item, site supervision, temporary power, equipment mobilization. Both differ from overhead, which spreads across every project a company runs, not just one.

Escalation

An adjustment added to material or labour pricing to account for expected cost increases between the time an estimate is prepared and when the work is actually purchased or performed, more relevant the longer a project's timeline stretches.

Contract Terms

Language that shows up once pricing turns into a signed agreement.

General Contractor (GC)

The party holding the prime contract with the project owner, responsible for overall project delivery and typically managing subcontractors.

Subcontractor (Sub)

A specialty trade contractor hired by the general contractor to perform a specific portion of the work, like electrical, plumbing, or drywall.

Change Order

A formal, signed document altering the original contract's scope, price, or schedule after work has begun.

Scope of Work

The written description of exactly what work is, and isn't, included under a specific contract or bid.

Holdback (Statutory Holdback)

A percentage of payment (typically 10 percent in most Canadian provinces) withheld from each progress payment until a lien period expires, a requirement under provincial construction lien or builders' lien legislation.

Tender

The formal process of submitting a priced bid in response to a project's bid documents, more commonly used in Canadian and Commonwealth construction language than the American term "bid."

Site & Construction Terms

Vocabulary that shows up once work actually starts on site.

CSI Division

A standardized category from MasterFormat, the numbering system organizing construction specifications and cost data (Division 03 Concrete, Division 09 Finishes, and so on), used across Canada to keep estimating and specification language consistent between firms.

Substantial Completion

The point at which a project is far enough along for its intended use, even if minor deficiencies remain, and a legally significant milestone that starts lien and warranty timelines in most provinces.

Punch List (Deficiency List)

A list of minor incomplete or incorrect items identified near the end of a project, that need correcting before final completion is signed off.

Mobilization

The setup work and cost involved in getting a crew, equipment, and site facilities ready before actual construction work begins.

Backfill

Soil or material replaced into an excavation after foundation or utility work is complete.

Means and Methods

The specific techniques, sequencing, and equipment a contractor chooses to complete the work, generally the contractor's own decision rather than something dictated by the drawings, unless a spec calls out a required method.

Overhead

A contractor's ongoing business costs not tied to a specific project, office rent, insurance, administrative staff, spread across jobs as a percentage rather than billed as a direct project cost.

General Conditions

Project-specific overhead costs that do belong to one job, site supervision, temporary facilities, permits, and site security, priced separately from the general contractor's company-wide overhead.

Scheduling & Risk Terms

Vocabulary that shows up once a project timeline and its risks get discussed formally.

Critical Path

The sequence of tasks in a project schedule that determines the shortest possible completion time, where a delay in any task on that path delays the whole project.

Float (Slack)

The amount of time a task can be delayed without affecting the project's overall completion date, applies only to tasks not on the critical path.

Milestone

A specific, dated point in a schedule marking a significant event, substantial completion, a permit approval, or a major inspection, used to track progress against the plan.

Force Majeure

A contract clause addressing events outside either party's control, severe weather, labour disruptions, or similar, that can excuse delay without penalty under specific conditions.

Lien (Construction Lien)

A legal claim registered against a property by a contractor, subcontractor, or supplier who hasn't been paid, giving them a security interest in the property until the debt is resolved, governed by provincial lien legislation across Canada.

Prime Contract

The direct contract between the project owner and the general contractor, as distinct from the subcontracts the GC signs with individual trades beneath that agreement.

Common Abbreviations Worth Knowing

These show up constantly on drawings with no explanation, since the drafter assumes you already know them.

"TYP" and "VIF" cause the most confusion for beginners specifically, TYP means the same detail repeats elsewhere without being redrawn each time, and VIF is a flag telling you the drawn dimension might not match site conditions exactly, so measure before ordering.

Using This Glossary Without Memorizing It

Nobody keeps all sixty of these terms loaded in working memory, and that's fine. What actually helps is knowing which category a confusing term probably belongs to, cost language behaves differently than contract language, which behaves differently than a drawing abbreviation, and narrowing the search that way is faster than scanning an alphabetical list top to bottom.

The terms that cost real money when confused are the pricing ones specifically, allowance versus contingency, markup versus margin. Those are worth actually committing to memory rather than looking up each time, since mixing them up doesn't just cause a communication hiccup, it changes what number ends up on an estimate.

Construction terminology isn't something anyone learns from a single glossary in one sitting. It builds the way most trade knowledge does, hearing a term on site, looking it up once, and having it stick a little better the second time it comes up. This list is meant to be the thing you come back to on that second or third encounter, not a vocabulary test to pass before starting.