Construction glossary

2D Two-Dimensional.
3D Three-Dimensional.
AC Alternating Current.
ACAS Advisory, Conciliation and Arbitration Service. A non-departmental public body whose purpose is to improve organisations and facilitate the practice of strong industrial relations.
Accident An event that results in an injury or ill-health.
ACOP Approved Codes of Practice. Legal guidance on hazardous materials and working practices.
Activities These are the construction tasks represented by bars on a Gantt chart or critical path analysis diagram. The arrows demonstrate the links between the tasks.
Albedo A measure of a surfaces ability to reflect solar radiation.
Alphanumeric organisational filing systems A method for classifying materials for storage and access through use of letters and digits that represents a concept. Alphanumeric filing systems typically use indirect access, with users locating file headings through a hierarchical or alphabetical list that indicates the code used for filing or retrieval.
AOD Above Ordnance Datum. The height of mean sea-level
Approved document One of the documents that the Secretary of State has approved that contains practical guidance on meeting the Building Regulations (2010) for England.
Baseline In relation to a project, a baseline states important conditions before a project begins, which can then be measured against to evaluate the project's progress.
Batten Strip of solid timber, nailed onto rafters, so that slates or tiles can be attached.
Bid A proposal or offer of a price.
BIM Building Information Modelling. Provides a multi-dimensional process for designers, building services engineers and structural engineers, helping them to explore a building before it is constructed, and to manage the project throughout the construction phase
Biomass A plant or animal material used for energy production, heat production, or in various industrial processes as raw material for a range of products.
BoQ Bill of Quantities. The measured items produced by a quantity surveyor for the complete project. Contains details of every item that is included within a project, together with a unit and total price for each item.
BREEAM Building Research Establishment Environmental Assessment Method. Is used for master-planning projects, infrastructure and buildings, when applied it recognises and reflects the value in higher performing assets across the built environment lifecycle.
Brownfield land / site Previously developed land in an urban area that is not currently in use; land which is now abandoned or only sparingly used but could be redeveloped.
Building survey This is a comprehensive report and is usually used for older properties or when major works are planned.
Built environment The human-made space in which people live, work, and recreate on a day-to-day basis; e.g. construction, operational energy uses, emissions from road and rail transport
Busbar An electrical conductor which is kept at a specific voltage and is capable of carrying a high current. It is usually used to make a common connection between several circuits in a system.
CAD Computer-Aided Design. The use of computers to aid in the creation, modification, analysis of a design.
Capacitance Capacitance is the ability of a component to store electrical charge.
Carbon dioxide A chemical compound composed of atoms. It is often referred to as CO₂.
Carbon dioxide emissions Carbon dioxide is released into the atmosphere naturally. However, when coal, petrol or diesel is burnt additional carbon dioxide is released. These additional emissions disturb the balance of gases in the atmosphere and have serious consequences such as climate change. It is therefore important to measure and control CO₂ emissions.
Cash flow The availability of cash or money in a business to pay salaries, purchase equipment, pay invoices and so on.
Cavity wall Cavity walls consist of two surfaces separated by a hollow space.
CAWS Common Arrangement of Work Sections.
CCAS Consumer Codes Approval Scheme.
CCC Committee on Climate Change.
CDBB Centre for Digital Built Britain. The Department for Business, Energy & Industrial Strategy and the University of Cambridge in partnership to deliver a smart digital economy for infrastructure and construction for the future and transform the UK construction industry.
CDM Construction (Design and Management) Regulations 2015. The main set of regulations for managing the health, safety and welfare of construction projects.
Change management process A formal process by which changes can be made to operational policy, procedures or documentation. The changes to the way somethings are done can then be communicated to all involved staff at the same time.
Check line This will often be drawn on to counter any errors, an extra line (known as a ‘check line’) is measured on the drawing and on the ground, which helps identify any errors.
Chute A steep and narrow slide, tube or shaft which can be used for conveying materials, e.g. waste, to a lower level.
Communication The exchange of information between individuals by means of speech, writing or some other method.
Competent Someone who has the necessary skills, training and expertise to complete the particular activity safely.
Concept drawings / sketches Freehand drawings used to demonstrate initial ideas.
Condition report This report provides information about the condition of the building, including serious defects and issues.
Conflict A disagreement or argument between individuals.
Conservation areas Local planning authorities are obliged to designate as conservation areas any parts of their own area that are of special architectural or historic interest, the character and appearance of which it is desirable to preserve or enhance.
Containment This is part of an electrical installation, which supports the cables in the wiring system and helps the finished result be aesthetically pleasing. Some examples are conduits, trunking and cable trays.
Contract management A method of procurement where a specialist management contractor is employed by the client to manage subcontractors and the overall process.
Contract specification A document providing detailed requirements for a project and incorporating the quality, materials and instructions for the contractor.
Contractors Separate companies who work for the main contractor, for example a mechanical and electrical engineering company.
Controlled waste This is building and demolition waste and household industrial and commercial waste.
COPA Control of Pollution Act 1974.
Corrective action Actions adopted to stop the problem from occurring again.
COSHH Control of Substances Hazardous to Health 2002.
CPA Critical Path Analysis. A technique of planning and analysing complex working procedures which focuses on the critical path to complete each component.
CPIC Construction Project Information Committee.
CPM Critical Path Method.
Damp proof course A treatment applied to domestic and commercial properties to prevent damp problems occurring.
Dangerous occurrences/Near miss An event that has the potential to cause injury or ill-health but doesn't cause harm in this particular instance of the event. E.g. a car crash occurs, but no one is injured, this is a near miss.
DC Direct current.
DEA Domestic Energy Assessor.
Deforestation The clearing of trees.
Delegation The assignment of any task or responsibility to another person.
Dependency Referring to the dependency of one activity on another, for example a roof cannot be started if the steelwork is not in position to support the roof cladding.
Desertification The process by which fertile land becomes a desert, typically as a result of drought, deforestation, or inappropriate agriculture.
Design and build Involves the client selecting the main contractor who then designs and constructs the building under one contract.
Design and build contract This is used on projects where contractors carry out both the design and construction work.
Drawing scales A way of depicting large real-life objects on a drawing. A scale uses a ratio to show how the size of a real object compares to the size of the same objects when it is drawn or made as a model
Drawings Drawings are the primary method of informing the contractor of the final design that has to be built.
Earned value method Any payments that are due are based on the value of the work completed.
Earthing A part required in an electrical system to prevent electric shocks. If anything goes wrong in the circuit, it directs the current into the earth via an alternative path.
EDM Electronic Distance Measuring.
EIA Environmental Impact Assessment. A measure that gives a CO₂ rating, which is graded from A to G.
Electrical properties Five key properties that affect that can affect the behaviour of electrical circuits and equipment: resistance, inductance, capacitance, reactance, impedance.
Elevation drawing Shows a 2-dimensional ‘picture’ of the building.
Embodied energy This is the sum total of the energy used throughout all of the processes included in the production of a building.
EMS Environmental Management System.
EPBD Energy Performance of Buildings Directive.
EPC Energy Performance Certificate. These certificates provide details of the energy efficiency and the environmental impact of a property.
EPC rating Energy efficiency performance is graded from A to G, with A being the most efficient. The environmental impact rating measure is also graded from A to G.
ESQC Electricity Safety, Quality and Continuity Regulations.
Estimate Roughly calculating or judging the costings of various elements of a project in order to give an approximate price.
Feasibility study An assessment of the practicality of a proposed construction which includes preliminary designs and budgets.
FIDIC International Federation of Consulting Engineers International Construction Contracts. Acronym is from its French name 'Fédération Internationale Des Ingénieurs-Conseils'.
Fixed price contract Where the overall price for the works is agreed before the work begins, also known as a conventional lump sum form of procurement.
Float or slack The amount of time an activity or project can be delayed from the start without the final completion date being affected.
Floor plans Shows a more detailed layout of each floor of the building.
Fluctuations Changes in rates of tax or VAT.
Footing A foundation of brick work, masonry or concrete under the base of a wall. It is used to distribute a load over a large area.
Fuel poverty A condition which means a household is unable to afford to keep their home adequately heated.
Functional unit According to NRM1 a functional unit is: ‘a unit of measurement used to represent the prime use of a building or part of a building (e.g. per bed space, per house and per m² of retail area). It also includes all associated circulation space.
Gantt chart A type of bar chart that illustrates a project schedule. This chart lists the tasks to be performed on the vertical axis, and time intervals on the horizontal axis. The width of the horizontal bars in the graph shows the duration of each activity.
Geothermal energy The heat from the Earth.
GGF Glass and Glazing Federation.
Greenfield land / site Undeveloped land in a city or rural area used for agriculture, landscaping, or left to develop naturally. This is land that has never been built on.
Greenhouse effect Warming that is caused when the Earth’s atmosphere traps heat that would otherwise be released into space.
Gutters Open piping attached to a roof to collect rainwater.
HASAWA Health and Safety at Work Act 1974.
Hazard Anything that may cause harm, such as chemicals, live wire, working on scaffolding, or a hot cup of coffee.
HIESS Home Insulation and Energy Systems Contractors’ Scheme.
HoC Height of Collimation.
HomeBuyer report This report informs the intended buyer about any work that may be required and can include a valuation.
HQM Home Quality Mark. A National standard to demonstrate the high quality of homes and to differentiate them in the marketplace.
HSE Health and Safety Executive. A UK government agency which enforces and regulates workplace health, safety and welfare
Illumination Brightening with light.
Impedance Impedance is the effective resistance of an AC electrical circuit caused by the combination of resistance and reactance.
Inductance This is the property of an electrical conductor by which a change in current produces an electromotive force (emf or voltage) in the conductor.
Inert waste Waste that will not decompose, for example, rubble, concrete or metal.
Instruction to tenderers A list of instructions to the tenderer, typically containing information and statements regarding the confidentiality of the tender as well as how long the contractor has to submit their bid.
Interim valuation Will ordinarily calculate the work that has been completed since the start of the project, with each monthly valuation being deducted from the total value. This results in a balance that is due for payment.
Invitation to tender letter Accompanies the other documents within the tender document and invites the potential contract to bid for the work, as well as instructions and the items the client expects the contractor to return should they want to make a bid.
Ironmongery The manufacturing of iron goods.
ITT Invitation To Tender.
JCT Joint Contracts Tribunal. A set of standard forms for documentation for use in the construction industry.
Just-in-time delivery system (JIT) Using a ‘just-in-time’ delivery system ensures that materials are delivered to the site when needed and reduces both waste and the requirement for storage on site. Using this method requires precise planning and monitoring of progress, to minimise the risk of delays and supply problems
Kinetic energy Energy that an object possesses due to its motion.
KPI Key Performance Indicator. A measurable value that reflects progress against objectives.
K-value A measure of the thermal conductivity of a material, i.e. how easily heat passes across it.
Labour The workers, craftspeople and managers, etc. who work on site; or the cost to employ people such as workers, tradesmen etc. in construction work
LED Light-emitting diode. A semiconductor light source that emits light when a current flows through it.
Lintel A horizontal block that sits across doors or windows to support the building material above.
Location plans Illustrate the position of the site and its surrounding areas.
Low-E glass Windows with a microscopically thin coating that is transparent and reflects heat.
Luminaires Any electrical light fitting that provides illumination.
MCS Microgeneration Certification Scheme.
Measurements An agreement on basic units for measuring angles, distances and more, it is needed to make accurate calculations.
MEP Mobile Elevated Platform.
Method statements Analyse the appropriate method to use in work activity and the sequence in which it should be done.
MHOR Manual Handling Operations Regulations 1992.
Most economically advantageous tender The tender that meets the majority of the criteria including price, quality and technical aspects.
Motor An electrical machine that converts electrical energy into mechanical energy.
NEC New Engineering Contract.
Negotiated tendering A single construction company is picked and a final contract price for the proposed work is negotiated.
Net cost The overall and final price, inclusive of labour, plan and materials (without any profit or overhead allowances).
NRM New rules of measurement. Published by RICS to provide a worldwide standard for the measurement and procurement of contract works that can be understood by all parties involved in a contract.
OJEU Official Journal of the European Union.
On-the-job training Learning through actually doing the relevant task or project.
Organic materials Carbon-based compounds, originally derived from living organisms.
OS maps Ordnance Survey maps. Detailed maps showing things such as footpaths, boundaries, places of interest and landscape features. Made by the OS which is the national mapping agency for Great Britain.
Overcurrent The Wiring Regulations describes overcurrent as 'a current exceeding the rated value. For conductors the rated value is the current-changing capacity.
Overhead The ongoing expense of operating a company or business, sometimes called operating expense.
Passivhaus An international energy performance standard. Passivhaus (also known as Passive House) is a design criteria and methodology which can be used in order to build houses that use a lot less energy than the standard house.
PDCA Plan, Do, Check, Act. A model that is used as part of a continuous improvement cycle. It consists of four stages
Peak Oil Peak Oil is the point in time when the maximum rate of crude oil extraction is reached, after which the rate of extraction is expected to begin to decline.
People who have an interest Involved parties that include operatives, tradespersons, consultants, contractors, subcontractors, suppliers, workforce.
Perspective drawing Gives a realistic view of the property and is good to show elevations and external views.
Plan Drawn from a bird’s eye top-down view, or as though everything has been pushed flat on a horizontal plane.
Plant The machinery or equipment required on site to transport, lift, move, cut or lay resources in construction.
PO Purchase Order. A commercial document as an official offer issued by a buyer.
Power factor The ratio of the actual power dissipated by an AC circuit to the product of the root mean squared (RMS) values of voltage and current.
PPE Personal Protective Equipment, e.g. gloves, hard hats
PQQ Pre-Qualification Questionnaire.
Pre-contract health and safety plan This is a requirement of the CDM regulations to assess the risks involved in the construction phase.
Prefabrication The process of manufacturing sections of a building that can then be transported to a site and quickly assembled.
Preliminary items Includes things like management costs, temporary works or site accommodation.
Procurement A process which involves numerous steps to aid in acquiring a project.
Profitability How much financial gain will be obtained from a construction project.
Programme of work Describes the sequence in which the work activities are to be carried out, so that the project can meet its set completion date.
Prolongation Costs resulting from disruption to the works or from delays to the works.
Putrescible waste Waste which will rot and decompose, for example, timber, food and paper.
PV Photovoltaics. A method for generating electric power by using solar cells to convert energy from the sun into a flow of electrons by the photovoltaic effect.
Quality standards and guidance This can include statutory requirements, contract requirements, project specifications, British standards, international standards, codes of practice, organisation standards, trade advisory guidance, best practice benchmarks and dimensional control criteria.
Quantity surveyor A professional who employs standard methods of measurement to develop a bill of quantities.
Rafter A structural component used as part of a roof to provide support for roof coverings.
RAMS Risk Assessment Method Statements. Documents companies create after they conduct risk assessments. RAMS documents contain details of the hazard as well as a step-by-step safe working guide that employees, contractors, and others can follow.
Reactance Reactance is the opposition to the flow of electrical current caused by the non-resistive components in a circuit (capacitative and inductive).
RECC Renewable Energy Consumer Code. Information on buying or leasing micro heat or power generation units.
Renewable energy sources Power generated from resources that are replenished naturally, e.g. sunlight, wind and rain.
Resistance Resistance is a measure of the opposition to the flow of electrical current.
Resources Includes equipment, plant, human resources and their associated costs. Activities can be resourced from the method statement. Quantities entered into a software resource application enables tracking and monitoring of resources.
Restrictive covenant A legal agreement or clause associated with particular land or property which may limit the use of the building.
Retention of payment The holding back of a percentage of a payment for a specific job or activity. This means that the contractor or subcontractor will not be paid the full amount until the work is completed and accepted.
RIBA Royal Institute of British Architects. Professional body for architects in the UK.
RICS Royal Institution of Chartered Surveyors. A professional body promoting and enforcing international standards in the valuation, management and development of land, real estate, construction and infrastructure.
RIDDOR Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 2013.
Safety committees Regular meetings held between employees and their employers to discuss and try to solve health and safety issues.
Schedules Schedules are prepared for the material elements of the build, e.g. room specifications, internal and external finishes and fittings and are based on the agreed design.
Section drawing A cross-section diagram, as if the object has been cut in half.
Selection criteria A list of factors the client considers valuable or important to a project, and what they want the potential tenderer to have in terms of skills or abilities. This can include price, previous work or project experience, health and safety track record and management skills
Selective tendering A select list of contractors is prepared by the designer and/or the client. All of those contracts then tender for the work
Sequencing Referring to the logical sequencing of activities, for example excavation of a foundation will precede concreting.
Serial tendering This method involves a single contractor being selected from a short-list to provide a series of contracts.
Shell A building shell includes all the elements that separate the interior spaces within the structure from the exterior areas. The shell is made up of many different features, such as walls, windows, doors, roofing, footers, and foundations.
Single phase Single phase is one of the two systems through which electricity is supplied. This system delivers to residential settings.
Site drawings Site drawings contain information that is specific to a site or project and contains information such as wiring diagrams, site plans, risk assessment and safety information. It must be reviewed before installation is carried out.
Skin When referring to buildings, the skin is the surface of the building that interacts with the world and is used to protect the contents. It can also be designed by the architects, so it also makes a statement about the building. Cavity walls have both internal and external skins.
Solar gain This is the increase in temperature of materials due to heat from the sun. It can be useful in cool climates, as a way of heating buildings.
SoW Schedules of Work.
Special waste Waste which is dangerous to keep or dispose of such as drugs, asbestos, pesticides and solvents.
Specification Provides detailed requirements for the project and incorporates quality, materials and instructions for the contractor.
SSSI Site of Special Scientific Interest, formal conservation designation.
STE Solar Thermal Energy. Technology harnessing energy from the sun to generate thermal or electrical energy to use in industry, e.g. using solar panels to generate electricity to heat an office.
Sustainable Procuring resources that can be used and/or ordered with minimal long-term impact on the environment.
SWMP Site Waste Management Plan. The purpose of a SWMP is to reduce the amount of waste that is produced on a construction site.
Systems Inspection, comparison with design requirements, comparison with standard documentation, checking manufacturer’s documentation, checking delivery notes, sampling and mock-ups, testing inspection reports, site meetings, dimension checks.
TBM Temporary Bench Marks. A marker used as a reference for level control during construction works and surveys
Tender An offer for the supply of goods and services, provided by a potential supplier. It is a formal offer presented to carry out the works for a stated fixed price
Tender and construction phase drawings Drawings to inform the contractor of the final design that has to be built and serve as a basis to allow contractors to price the works with a reasonable degree of accuracy.
Tender document Comprises a number of items, such as a description of the project, the specification and a condition of the contract.
Tender drawing register This lists all the drawings that accompany the tender, they should be numbered and referenced.
Tender drawings These are produced by the designer/architect and include floor plans, elevations and section drawings.
TER Target Emission Rate. A limit setting a minimum allowable standard for the energy performance of a building. It is defined by the annual CO₂ emissions of a notional building of same type, size and shape to the proposed building. TER is expressed in annual kg of CO₂ per sq. m.
Term contract Generally used for minor maintenance works.
TFEE Target Fabric Energy Efficiency rate. The energy demand in units of kilowatt-hours per square metre of floor area per year.
Three-phase This is one of the two systems through which electricity is supplied. This system delivers to industrial settings, where there is a higher volume required.
Timescale The duration time an activity or a sequence of activities take.
Toolbox talk An informal meeting that focuses on health and safety in the workplace.
Traditional procurement The client chooses a designer who produces a design to the agreed requirements. A main contractor is then chosen and completes the project up to handover. The initial designer supervises the work for its duration
Transformer Apparatus for increasing or reducing the voltage of an alternating current.
TSI Trading Standards Institute.
Two-stage tendering A number of potential contractors present their proposals for the project. From there, they draft an approximate bill of quantities to compete in their tender for the work. A final design and tender is submitted from the most competitive bid
UNFCCC United Nations Framework Convention on Climate Change.
Unfixed materials Materials that have been delivered to site but are not yet installed or being used.
Unit cost The cost for one measured unit of work activity upon completion.
Unit or number method This method estimates costs using a physical unit e.g. a hospital bed, or a seat in a stadium. There is not a high degree of accuracy and estimated costs can vary significantly from actual costs, and the historical design versus the provisional design would have a substantial impact on the actual costs.
Urbanisation The expansion of urban areas.
U-value U-values are used to measure how effective the different materials or elements of a building are as insulators. Giving the transfer rate of heat through a structure, divided by the difference in temperature across that structure.
Value engineering A process designed to maximise value principally through either improved design or function but can also reduce construction costs and/or reduce the cost of the operational building.
Variation Additions or alterations to the planned designs which weren't in the initial agreed project scope. Variations are common in construction as much can change throughout the duration of a project.
VAT Value-Added Tax.
Visual inspection Visual inspections must be carried out before an installation is started. It takes into consideration safety aspects such as how safe the current equipment is, and the safety of people who may be affected by the work.
Waste Waste is any substance which constitutes a scrap material or effluent or otherwise any unwanted surplus arising from the application of any process, or any substance or article which requires disposal because of being broken, worn out, contaminated or otherwise spoiled.
WEEE regulations Waste Electrical and Electronic Equipment Regulations 2006.
Well-conditioned triangles Points on a survey that make roughly equilateral triangles with internal angles ranging from 30° to 120°. These should be drawn as large as possible so that when the framework is plotted, no errors show up
Wind turbine A device that converts the wind’s kinetic energy into electrical energy.