Reference
Civil construction glossary
90 terms from the field, the spec book and the contract, in plain language.
- Adjudication
- A fast, interim dispute-resolution process created by prompt payment legislation, in which an independent adjudicator decides a payment dispute on a short timeline, without stopping work on the project. →
- Aggregate
- Crushed rock, gravel or sand used as a bulk construction material, ranging from unprocessed pit run to tightly graded base course and concrete aggregate. →
- Asphalt (hot-mix asphalt)
- A paving material made of aggregate bound together with heated liquid asphalt cement, mixed at a plant, placed hot and compacted with rollers to form a road or lot surface. →
- Backfill
- Material placed back into an excavation around or above a pipe, structure or foundation, usually in controlled, compacted layers rather than dumped in all at once. →
- Bank cubic metre
- A volume of soil or rock measured in its natural, undisturbed state before excavation, as opposed to the larger loose volume it occupies once dug or the smaller volume it occupies once compacted. → →
- Base course
- A layer of crushed, well-graded aggregate placed directly beneath a paved or gravel road surface, spreading traffic loads and providing drainage. →
- Bedding
- A layer of select material, usually granular, placed in the bottom of a trench to support a pipe evenly along its length before backfill goes in around and above it. → →
- Benching
- A method of protecting workers in an excavation by cutting the walls back in a series of horizontal steps rather than a single continuous slope. →
- Bid bond
- A bond submitted with a tender that assures the owner the bidder will sign the contract and provide the required performance and payment bonds if awarded the work, with the surety responsible if the bidder walks away. → →
- Borrow
- Fill material brought in from an outside source, typically a pit, when the material excavated on site is not enough or not suitable to build the required embankment or fill. →
- Builders lien
- A legal claim that a contractor, subcontractor or supplier can register against a property to secure payment for work or materials they provided, under provincial lien legislation. →
- California Bearing Ratio (CBR)
- A laboratory or field test that measures the strength of a subgrade or aggregate relative to a standard crushed stone, used as an input to pavement thickness design. →
- Change order
- A written amendment to a construction contract that adds, removes or alters scope, and adjusts the contract price and schedule to match. →
- Chip seal
- A pavement surface treatment in which liquid asphalt is sprayed onto a road and covered with a layer of aggregate chips, then rolled, commonly used to reseal or protect an existing surface rather than build a new one. →
- Clearing and grubbing
- Removing trees, brush and stumps, including their root systems, from a site before earthworks or construction begins. → →
- Cold joint
- A joint in a concrete pour formed when fresh concrete is placed against concrete that has already begun to set, which can leave a visible line and a plane of weakness if not properly prepared. →
- Compaction
- Mechanically compressing soil, aggregate or asphalt to reduce air voids and increase density, using rollers, plate compactors or rammers, so the material can carry load without excessive settlement. →
- Competent person
- Under occupational health and safety regulations, a worker with the knowledge, training and experience to identify hazards on a site, and the authority to take corrective action. →
- Crown
- The slope built into a road's cross-section, higher at the centre than at the edges, so surface water sheds toward the ditches or gutters rather than pooling on the driving surface. →
- Culvert
- A structure, usually a pipe or box section, that carries water under a road, railway or other embankment, allowing a stream or ditch to pass beneath the crossing. → →
- Curb and gutter
- A concrete edge structure along a road that defines the pavement edge and channels surface water along the gutter line to a catch basin or ditch. →
- Cured-in-place pipe (CIPP)
- A trenchless rehabilitation method that installs a resin-saturated liner inside an existing pipe and cures it in place, forming a new pipe within the old one without excavating along its length. →
- Deep well (dewatering)
- An individually pumped well, drilled around or within an excavation, used to lower the groundwater table where shallower well points cannot reach the needed depth. →
- Directional drilling (HDD)
- A trenchless method that bores a steerable underground path for a pipe or conduit from the surface, avoiding an open trench along most of the route. → →
- Discharge permit
- An approval from a municipality or province authorizing water, such as water pumped during dewatering, to be released into a sewer, ditch or natural watercourse. →
- Eductor
- A jet-pump dewatering system that uses a pressurized water supply to draw groundwater up through a well, used where soil is too fine for standard well points to work efficiently. →
- Embankment
- Fill material placed and compacted in layers to raise the ground to a design elevation, commonly used to carry a road or railway above the surrounding grade. →
- Erosion and sediment control (ESC)
- Temporary measures, such as silt fence, check dams and stabilized entrances, installed before and during construction to keep sediment from leaving a site in runoff. →
- Expansion joint
- A gap built into a concrete structure, filled with a compressible material, that allows adjoining sections to move slightly with temperature change without cracking each other. →
- Forcemain
- A pressurized pipe that carries wastewater uphill or over a distance using a pump, as opposed to a gravity sewer that relies on a continuous downhill slope alone. →
- Formwork
- Temporary moulds, typically built from wood, steel or engineered panels, that hold wet concrete in its designed shape until it has cured enough to support itself. →
- Frost depth
- How far below the ground surface the soil freezes over winter, which sets the minimum burial depth for footings and buried pipe in a given climate. →
- General contractor
- The contractor holding the main construction contract with the owner, responsible for coordinating the subcontractors, suppliers and schedule needed to deliver the whole project. →
- Geotextile
- A permeable fabric placed between soil layers or beneath aggregate to separate them, reinforce the ground or aid drainage, without blocking the flow of water. →
- Gradation
- The distribution of particle sizes within an aggregate sample, from coarse rock down to fine sand, used to specify and test base, subbase and concrete materials. →
- Granular base
- A layer of crushed, well-graded aggregate placed beneath a road, pad or other structure to spread load and provide drainage above the subgrade. →
- Gravity sewer
- A sewer pipe sloped so that wastewater flows by gravity alone, without pumping, from its source toward a treatment plant or lift station. →
- Hazardous materials survey
- An inspection, often including sampling, of a building or structure before demolition or renovation, to identify designated substances such as asbestos and lead that need to be managed or removed first. →
- Holdback
- A portion of each progress payment on a construction contract withheld by the payer for a set period after substantial performance, protecting subcontractors and suppliers who hold lien rights against the project. →
- Inverted siphon
- A section of gravity sewer or watermain that dips below an obstruction, such as a waterway or another utility, relying on pressure to keep the flow moving rather than a continuous downhill slope. →
- Lift (earthworks)
- A single layer of fill placed and compacted before the next layer goes on top of it, used to build an embankment or backfill to a controlled density. →
- Lift station
- A pumping facility that raises wastewater from a lower point in a sewer system to a higher one, so it can continue flowing by gravity or reach a treatment plant. →
- Liquidated damages
- A pre-agreed amount, set out in a contract, that an owner may deduct from a contractor for each period a project runs past its agreed completion date, in place of proving the owner's actual loss. →
- Locate
- The process of identifying and marking the position of a buried utility on the ground before excavation, usually requested through a one-call or click-before-you-dig centre. →
- Locate marking colour code
- A shared colour standard used across Canada to mark, with spray paint or flags, the type of buried utility present or a temporary survey line before excavation. →
- Loose volume
- The volume a material occupies once it has been excavated and bulks up, larger than its original bank volume in the undisturbed ground. →
- Lot grading
- Shaping the finished ground surface around a building lot so surface water drains away from foundations and toward the street or a storm system, typically certified against an approved grading plan. → →
- Lump-sum contract
- A contract that prices an entire defined scope of work as a single fixed amount, as opposed to a unit-price contract paid against measured quantities. →
- Manhole
- A vertical access structure built into a sewer or watermain system, allowing workers to inspect, maintain or connect to the pipe below ground. →
- Microtunnelling
- A trenchless method that uses a remotely controlled boring machine to install pipe below ground on a precise line and grade, typically used for larger-diameter gravity sewers. →
- Milling
- Removing the top layer of an existing asphalt surface with a specialized machine, either to prepare the surface for a new overlay or to recover reusable material. → →
- Mobilization
- The cost and effort of moving equipment, materials and crews to a site before work begins; demobilization is the equivalent process at the end of a job. →
- One-call centre
- An organization that receives a single excavation notice and forwards it to member utility owners in the area, who then locate and mark their own buried infrastructure. →
- Payment bond
- A bond that assures a contractor's subcontractors and suppliers will be paid for labour and material they provide, with the surety responsible for payment if the contractor defaults. →
- Performance bond
- A bond that assures a project owner a contractor will complete the contracted work, with the surety responsible for arranging completion or covering the cost if the contractor fails to perform. →
- Pier
- A vertical support structure, typically concrete, that carries a bridge deck or other structure down to its foundation, positioned between the abutments at each end of the span. →
- Pile (piling)
- A long structural element, typically steel, concrete or timber, driven or drilled into the ground to transfer a structure's load down to stronger soil or rock. → →
- Pit run
- Gravel taken from a pit with little or no processing, as opposed to gravel that has been crushed and screened to a specified gradation. →
- Prime coat
- A light application of liquid asphalt applied to a granular base before paving, intended to bind the surface and improve adhesion of the asphalt layer placed above it. →
- Proctor test
- A laboratory test that establishes the relationship between a soil's moisture content and the density it can be compacted to, used as the benchmark that field compaction testing is measured against. →
- Prompt payment
- Legislation in several Canadian provinces that sets fixed timelines for an owner to pay a contractor, and for a contractor to pay its subcontractors, along with a fast adjudication process for resolving payment disputes. →
- Proof-roll
- Driving a heavy, loaded vehicle such as a roller or loaded truck over a compacted subgrade or base to find soft spots before the next layer is placed. →
- Punch list
- A list of minor deficiencies identified near the end of a project that need to be corrected before the owner accepts the work as complete. →
- Rebar (reinforcing steel)
- Steel bar embedded in concrete to carry tension loads that plain concrete cannot resist on its own, typically placed in a grid or cage before the pour. →
- Reduced load period (spring road ban)
- A provincially designated period, generally during spring thaw, when heavy vehicles are restricted to reduced axle weights on certain roads to protect the road structure while it is most vulnerable. →
- Request for proposal (RFP)
- A procurement document that asks bidders to propose an approach and a price for a scope of work, evaluated against criteria beyond price alone, as opposed to a straightforward lowest-price tender. →
- Right-of-way
- A strip of land, publicly or privately held, set aside for a road, utility or other linear piece of infrastructure to pass through. →
- Riprap
- Placed rock, sized and graded to resist movement, used to protect a bank, shoreline or structure from erosion caused by water or wave action. →
- Shoring
- A temporary structural system, such as a trench box, hydraulic shore or engineered bracing, that supports the walls of an excavation to protect workers inside it. →
- Shrink factor
- The ratio describing how much a material's volume decreases once it is compacted, relative to its original bank volume. →
- Site servicing agreement
- An agreement between a developer and a municipality setting out the underground and road infrastructure the developer must build, and often the levies it must pay, before new lots can be built on. → →
- Slope (cut-back slope)
- The angle at which the walls of an excavation are cut back from vertical, used as an alternative to shoring where soil conditions and available space allow it. → →
- Slump test
- A field test that measures the consistency of fresh concrete by how far a sample slumps after a cone mould is removed, used to check that a delivery matches its specified mix. →
- Specification (spec)
- The written technical requirements published by an owner, such as a municipality or provincial transportation ministry, setting out materials, methods and acceptance criteria for construction work. →
- Spoil
- Excavated material set aside beside an excavation, either for reuse as backfill or for disposal once the work is complete. →
- Standard drawing
- A pre-approved detail drawing, published by an owner, showing how a common structure such as a catch basin, curb ramp or manhole is to be built. →
- Subbase
- A granular layer beneath a road's base course, providing additional load distribution and drainage above the prepared subgrade. →
- Subgrade
- The native or prepared soil surface beneath a road, pad or floor structure, shaped and compacted to support the granular and paved layers above it. → →
- Substantial performance
- The point in a construction contract, defined by provincial lien legislation, at which the work is far enough along to be used for its intended purpose, which starts the clock on holdback release and lien deadlines. →
- Sump
- A pit dug at the low point of an excavation, into which groundwater collects so it can be pumped out. →
- Swell factor
- The ratio describing how much a material's volume increases once it is excavated and loosened, relative to its original bank volume. →
- Tack coat
- A thin application of liquid asphalt applied between an existing pavement layer and a new asphalt lift, to bond the two together. →
- Tender
- A formal bid submitted in response to a public or private call for construction work, typically priced on a unit-price or lump-sum basis and awarded to the lowest compliant bidder. → →
- Trench box
- A prefabricated steel shielding structure lowered into a trench to protect workers from a wall collapse, used as an alternative to sloping or engineered shoring. →
- Unit-price contract
- A contract that pays for work based on measured quantities of each item, at a fixed rate per unit, as opposed to a lump-sum contract priced as a single fixed total. →
- Watermain
- A pressurized pipe that distributes treated drinking water from a treatment plant or reservoir to homes, businesses and fire hydrants. → →
- Well point
- A small-diameter well connected to a common header pipe and vacuum pump, used in a line around an excavation to draw down the groundwater table. →
- Wharf
- A structure built along a shoreline, usually pile-supported, where vessels can berth to load, unload or provide public access to the water. →
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The locate colour code
- White Proposed excavation
- Pink Temporary survey markings
- Red Electric power lines, cables, conduit and lighting cables
- Yellow Gas, oil, steam, petroleum or gaseous materials
- Orange Communication, alarm or signal lines, cables or conduit
- Blue Potable water
- Green Sewers and drain lines
- Purple Reclaimed water, irrigation and slurry lines
Canadian Common Ground Alliance, Best Practices v3.0: uniform colour code.