Glossary of planning, building and contract terms

Plain definitions of the terms used across these guides, for England, with a link to the guide that covers each one where there is one.

Adjacent excavation notice

Notice under section 6 of the Party Wall etc. Act 1996, needed where you excavate within 3 metres of a neighbour's building or structure and below the bottom of its foundations, or within 6 metres where the excavation would reach below a line drawn down at 45 degrees from the bottom of its foundations. It must be served at least one month before the work starts. See the 3 metre and 6 metre rules.

Adjoining owner

Under the Party Wall etc. Act 1996, the owner of land or buildings next to the building owner's, and for adjacent excavation, the owner of a building within the 3 metre or 6 metre distances (section 20).

Adjudication

A quick, interim way of settling a construction dispute through an independent adjudicator, who must decide within 28 days of referral unless a longer period is agreed. The Construction Act gives the right (section 108), but not on a contract with a residential occupier. JCT's Home Owner contracts include adjudication by contract.

Approved Documents

Government guidance on ways of meeting the Building Regulations, approved under section 6 of the Building Act 1984. Following them is not compulsory, but compliance can be relied on as tending to show the regulations were met, and failure as tending to show they were not (section 7).

Article 2(3) land

The areas listed in Schedule 1, Part 1 of the GPDO 2015: conservation areas, areas of outstanding natural beauty, the Broads, National Parks, World Heritage Sites and land specified under section 41(3) of the Wildlife and Countryside Act 1981. Several permitted development rights are narrower there. See what is permitted development.

Article 4 direction

A direction under article 4 of the GPDO 2015 that removes specified permitted development rights, across an area or for a particular development, so that a planning application is needed instead. See Article 4 directions.

Bill of quantities

A list of items giving detailed descriptions and firm quantities of all the work in a contract, usually prepared by a quantity surveyor under the RICS measurement rules, NRM 2. See schedules of works.

Building control body

The body that checks building work against the Building Regulations: the local authority, or a registered building control approver. See council building control or a registered approver.

Building notice

A notice to the local authority of intended building work, given without first getting plans approved (Building Regulations 2010, regulations 12(2)(a) and 13). It cannot be used for work to buildings covered by the Regulatory Reform (Fire Safety) Order 2005, for a new building fronting a private street, or for work subject to requirement H4: building over, or obstructing access to, a drain or sewer shown on the sewerage undertaker's map (regulation 12(3) to (5)). See full plans or building notice.

Building owner

Under the Party Wall etc. Act 1996, an owner of land who wants to exercise rights under the Act: usually the person having the work done (section 20).

Building Regulations

The Building Regulations 2010, made under the Building Act 1984, which set the legal requirements for building work in England, from structure and fire safety to energy use. See do you need Building Regulations approval?

CDM 2015

The Construction (Design and Management) Regulations 2015, which set health and safety duties for clients, designers and contractors on construction work, including work on people's homes. ClearCDM explains how CDM applies to domestic projects.

Certificate of making good

Under a JCT contract, the certificate the contract administrator issues once the defects listed in the rectification period have been put right. The rest of any retention follows it. See practical completion and the rectification period.

CIL (Community Infrastructure Levy)

A charge councils can set on new building, under Part 11 of the Planning Act 2008 and the Community Infrastructure Levy Regulations 2010. An extension with less than 100 square metres of new gross internal area and no new dwelling is not liable (regulation 42); larger extensions and annexes can be exempt if the exemption is claimed before work starts. See CIL on an extension.

Commencement notice

For CIL, the notice (Form 6) that must reach the council no later than the day before a chargeable development starts (CIL Regulations 2010, regulation 67). It is not needed where regulation 42 applies or an exemption for a residential extension has been granted. Separately, the Building Regulations require notice to the local authority at least two days before work starts (regulation 16(1)) and within five days after it is to be regarded as commenced (regulation 16(3C)). See how householders lose CIL exemptions.

Competent person scheme

A scheme whose registered installers can carry out certain work, such as some electrical, heating and window work, without a building notice or full plans application (Building Regulations 2010, regulation 12(6) and Schedule 3).

Completion certificate

The certificate a local authority gives when satisfied, after taking all reasonable steps, that completed building work meets the relevant requirements (Building Regulations 2010, regulation 17). It is evidence, but not conclusive evidence, of compliance. A registered building control approver gives a final certificate instead. See a missing completion certificate.

Conservation area

An area of special architectural or historic interest, the character or appearance of which it is desirable to preserve or enhance, designated by the council under section 69 of the Planning (Listed Buildings and Conservation Areas) Act 1990. It is Article 2(3) land, and trees in it are protected. See living in a conservation area.

Construction Act

The usual name for Part II of the Housing Grants, Construction and Regeneration Act 1996, as amended: the statutory rules on adjudication and payment in construction contracts. It does not apply to a contract with a residential occupier (section 106).

Contingency

Your own allowance in the budget for the unexpected. It is not the same as a provisional sum, which is a named item in the tender documents. See contingency.

Contract administrator

The person who runs a building contract for the client: issuing instructions, valuing work and certifying payments, deciding extensions of time and certifying completion. Anyone competent may hold the role. See what a contract administrator does.

Contract particulars

The part of a JCT contract where the project's own details are entered: dates, liquidated damages, the rectification period, payment intervals, retention percentages and the insurance option. See how to tender building work.

Contractor's designed portion

A part of the work the contractor designs within an otherwise traditional contract, such as JCT's MWD 2024 or ICD 2024. JCT is clear this is not design and build.

Cost plan

A breakdown of expected construction cost, prepared early and updated as the design develops. See what a cost plan contains.

Curtilage

The land that goes with a building, usually its garden. Planning law uses the term without a general statutory definition, so where the boundary lies can be disputed.

Dayworks

A way of valuing work by the time spent by the contractor's team, the materials used and the plant employed (RICS NRM 2).

Deemed dispute

Under the Party Wall etc. Act 1996, the dispute that arises automatically when an adjoining owner does not consent in writing within 14 days to a party structure notice or an adjacent excavation notice (sections 5 and 6(7)). Surveyors then settle it under section 10. See when a neighbour does not respond.

Design and build

A procurement route in which the contractor completes the design and builds for a price. JCT's Design and Build Contract has no independent contract administrator; the client acts, or appoints an agent. See traditional or design and build.

Development

In planning law, building, engineering, mining or other operations in, on, over or under land, or a material change of use (Town and Country Planning Act 1990, section 55). Development needs planning permission, which the GPDO grants for some classes.

Domestic client

Under CDM 2015, a client having work done that is not in the course or furtherance of a business (regulation 2). Most of a domestic client's duties pass to the contractor, the principal contractor or, by written agreement, the principal designer (regulation 7).

Employer's requirements

In JCT's design and build contracts, the client's statement of what is to be designed and built. The contractor's proposals respond to it, and where the requirements conflict internally, the proposals prevail.

Enforcement time limit

The period after which a council can no longer take enforcement action against a breach of planning control. In England it is ten years (Town and Country Planning Act 1990, section 171B, as amended from 25 April 2024). Building operations substantially completed before that date keep the old four-year limit. See the 10-year enforcement rule.

Extension of time

More time to finish, given to the contractor under the contract for delay it is not responsible for. JCT's Minor Works allows it for delay beyond the contractor's control; larger JCT forms list the events that qualify.

Final certificate

Under a JCT contract, the contract administrator's last certificate, settling the final sum due. In building control, the certificate a registered building control approver gives when the work is complete.

Full plans

An application for building control approval with full plans (Building Regulations 2010, regulation 14). The local authority must notify the outcome within five weeks, or a longer period agreed in writing, and silence is neither approval nor rejection (regulation 14A(6) and (7)). An approval lapses if the work has not started within three years of the application (Building Act 1984, section 32). See full plans or building notice.

GPDO

The Town and Country Planning (General Permitted Development) (England) Order 2015, which grants planning permission for defined classes of development. Householder extensions and alterations are in Schedule 2, Part 1. See what is permitted development.

Health and safety file

Under CDM 2015, the file the principal designer prepares with the information needed for future work on the building, kept available for anyone who may need it to comply with the law (regulation 4(5)(b)).

Householder application

An application for planning permission for development of an existing house, or within its curtilage for a purpose incidental to enjoying it. It excludes a change of use and a change in the number of dwellings (Development Management Procedure Order 2015, article 2). See planning fees and timescales.

Interim certificate

A certificate issued during the work stating the sum due to the contractor at an interim valuation date. Under JCT's Minor Works the contract administrator issues it.

JCT

The Joint Contracts Tribunal, which publishes standard forms of building contract, including the Home Owner contracts (HO/B and HO/C 2021), Minor Works (MW 2024), Intermediate (IC 2024) and Design and Build (DB 2024). See which building contract.

Larger home extension

A single-storey rear extension beyond the ordinary permitted development limits: up to 8 metres for a detached house or 6 metres for any other house, and no more than 4 metres high (GPDO 2015, Schedule 2, Part 1, paragraph A.1(g)). It needs the prior approval process in paragraph A.4, and is not available on Article 2(3) land or a site of special scientific interest. See larger rear extensions.

Lawful development certificate

A certificate from the council that an existing use or operation (Town and Country Planning Act 1990, section 191), or a proposed one (section 192), is lawful. See lawful development certificates.

Line of junction notice

Notice under section 1 of the Party Wall etc. Act 1996 to build a new wall on the boundary, served at least one month before work starts. If the neighbour has not consented to a wall astride the line within 14 days, the building owner may build only wholly on their own land (section 1(4)); that is not a dispute. See party wall notice periods.

Liquidated damages

A rate stated in a building contract that the client may deduct if the contractor finishes late without an entitlement to more time. Under JCT's Minor Works the rate and period go in the contract particulars (clause 2.8).

Listed building

A building on a list of buildings of special architectural or historic interest compiled or approved by the Secretary of State (Planning (Listed Buildings and Conservation Areas) Act 1990, section 1).

Listed building consent

Consent needed to demolish a listed building, or to alter or extend it in any way that would affect its character as a building of special architectural or historic interest (section 7 of the 1990 Act). There is no application fee. See listed building consent.

Loss and expense

Money a contractor can claim under larger JCT contracts for disruption caused by specified matters. JCT's Minor Works has no express provision for it.

Lump sum contract

A contract in which the contractor does a defined amount of work for a price agreed before work starts, the contract sum, which changes only as the contract allows.

Material operation

Work that counts as beginning development for planning time limits, such as construction work, demolition or digging a foundation trench (Town and Country Planning Act 1990, section 56(4)). In England a planning permission must be begun within three years unless it says otherwise (section 91).

NEC

A family of standard contracts published by NEC, part of the Institution of Civil Engineers' commercial arm, Thomas Telford Ltd. The NEC4 Engineering and Construction Short Contract is for straightforward, low-risk work.

Non-material amendment

A change the council can make to a planning permission when satisfied the change is not material (Town and Country Planning Act 1990, section 96A).

Original house

For permitted development, the house as it stood on 1 July 1948, or as built if built after that date (GPDO 2015, article 2(1)). Extensions added since count against the limits. See the original house.

Party structure notice

Notice under section 3 of the Party Wall etc. Act 1996 for work to an existing party wall or party structure, such as cutting into it to take the bearing of a beam. It must be served at least two months before work starts, and lapses if the work has not begun within 12 months and is not prosecuted with due diligence (section 3(2)(b)). See party wall notice periods.

Party wall

A wall forming part of a building that stands on the land of two owners beyond the projection of its footings, or the part of any other wall that separates buildings belonging to different owners (Party Wall etc. Act 1996, section 20). See do you need a party wall agreement?

Party wall award

The document in which the surveyor or surveyors settle a party wall dispute: the right to do the work, the time and manner of doing it, and costs (section 10(12)). Either owner may appeal to the county court within 14 days of it being served (section 10(17)).

Party wall surveyor

A person appointed under section 10 of the Party Wall etc. Act 1996 to settle a dispute: one agreed surveyor, or one for each owner who together select a third. The Act defines a surveyor as any person who is not a party to the matter (section 20). See party wall surveyor costs.

Pay less notice

A notice that the payer intends to pay less than the sum notified as due, stating the sum it considers due and how it was calculated (Housing Grants, Construction and Regeneration Act 1996, section 111). Not required by statute on a contract with a residential occupier; JCT's Minor Works includes one by contract. See payment and retention for homeowners.

Payment notice

A notice stating the sum due at a payment due date and how it was calculated, given no later than five days after that date (section 110A of the 1996 Act).

Permitted development

Development granted planning permission by the GPDO 2015 instead of by an application, within the limits and conditions of each class. See what is permitted development.

Planning condition

A requirement attached to a planning permission, for example on materials, or on details to be approved before work starts. Development without complying with a condition can be applied for under section 73.

Planning permission

Permission for development under the Town and Country Planning Act 1990, granted by the council on an application, or by the GPDO for permitted development. See anyone can submit a planning application.

Practical completion

The point at which the contract administrator certifies the building work complete under a JCT contract. Most JCT forms do not define it; the Court of Appeal has held that defects which are more than trifling prevent it. See practical completion and the rectification period.

Pre-application advice

Advice from the council on a proposal before an application is made. See pre-application advice.

Pre-construction information

Under CDM 2015, information in the client's possession or reasonably obtainable that is relevant to the construction work, including hazards and any existing health and safety file (regulation 2). It must go to every designer and contractor appointed or being considered for appointment (regulation 4(4)).

Preliminaries

The contractor's costs that are not tied to any one item of work, such as management, site set-up, security and safety (RICS NRM 2).

Prime cost sum

A supply-only allowance within a rate for materials or goods whose exact quality has not yet been chosen, such as tiles at a stated price per square metre. Fixing and the contractor's overheads are priced separately (RICS NRM 2). See schedules of works.

Principal contractor

The contractor appointed in writing to control the construction phase where more than one contractor will work on a project. The role exists under CDM 2015 (regulation 5) and under Part 2A of the Building Regulations 2010 (regulation 11D).

Principal designer

The designer appointed in writing to control the design work where more than one contractor will work on a project. There are two roles: one under CDM 2015 (regulation 5), for health and safety, and one under the Building Regulations 2010 (regulations 11D and 11M), for compliance with building regulations. A client can certify the CDM appointee as holding the Building Regulations role too (regulation 11D(2)). See the two principal designer roles.

Prior approval

A process under the GPDO in which the council approves specified aspects of permitted development before it goes ahead. For a larger home extension the council has 42 days, and neighbours get at least 21 days to comment (Schedule 2, Part 1, paragraph A.4). See larger rear extensions.

Provisional sum

A sum set aside in the tender documents for work that cannot yet be fully described or quantified. RICS NRM 2 divides them into defined and undefined sums; for an undefined sum the contractor is assumed to have made no allowance in its programme or preliminaries. See schedules of works.

Quantity surveyor

A cost consultant who prepares cost plans, bills of quantities and valuations. See do you need a quantity surveyor?

Reasonable care and skill

The standard every trader supplying a service to a consumer must meet (Consumer Rights Act 2015, section 49). A contract term cannot exclude it (section 57(1)).

Rectification period

The period after practical completion during which the contractor must return to put right defects that appear. Its length is stated in the contract particulars. See practical completion and the rectification period.

Registered building control approver

A private building control body, the alternative to the local authority. It takes on a project by giving an initial notice and issues a final certificate when the work is complete (Building (Registered Building Control Approvers etc.) (England) Regulations 2024). See council building control or a registered approver.

Regularisation certificate

A certificate a local authority may give for building work done without approval on or after 11 November 1985, once satisfied that it meets the requirements that applied when it was done (Building Regulations 2010, regulation 18). See regularisation certificates.

Residential occupier

For the Construction Act, a contract with a residential occupier is one that principally relates to work on a dwelling that one of the parties occupies, or intends to occupy, as a residence. The Act's payment and adjudication rules do not apply to it (section 106). See payment and retention for homeowners.

Retention

A percentage of each payment held back by the client as security against defects. Under JCT's Minor Works the contract particulars set one percentage before practical completion and another after it, so part is released at practical completion and the rest after defects have been made good. See payment and retention for homeowners.

RIBA Plan of Work 2020

A published framework that divides a building project into eight stages, from 0 Strategic Definition to 7 Use. See the stages of a home project.

Schedule of rates

A list of rates for items of work. Under JCT contracts it can be the priced document behind a lump sum, used to value changes.

Schedule of works

A list of the building work, item by item, that contractors price against. JCT calls it work schedules. See schedules of works.

Scheme for Construction Contracts

The default terms that apply where a construction contract does not meet the Construction Act's requirements on adjudication or payment. Like the rest of the Act, it does not reach a contract with a residential occupier.

Section 73 application

An application for planning permission to carry out development without complying with conditions attached to an earlier permission (Town and Country Planning Act 1990, section 73).

Self-build exemption

A CIL exemption for a person who builds, or commissions, a home and lives in it as their sole or main residence (CIL Regulations 2010, regulation 54A). It must be claimed before work starts (regulation 54B), and is withdrawn if, for example, the home is sold or let within the three-year clawback period (regulation 54D). See the CIL self-build exemption.

Snagging

Listing and fixing minor defects at or near completion. JCT's Standard and Design and Build contracts do not require a snagging list, and a defect that is more than trifling means the work is not practically complete, whatever list it is on.

Specification

A document that sets the standard of materials and workmanship for the work. See schedules of works.

Stage payment

A payment made when an agreed stage of the work is complete. The Construction Act gives a right to instalments unless the work is to last less than 45 days (section 109), but not on a contract with a residential occupier, where it depends on the contract. See payment and retention for homeowners.

Tender

A contractor's formal offer to carry out defined work for a price, made in response to an invitation; also the process of inviting those offers. See how to tender building work.

Traditional procurement

A route in which the client's designers complete the design before contractors price it, and a contract administrator runs the contract. See traditional or design and build.

Tree preservation order

An order a council makes under section 198 of the Town and Country Planning Act 1990 to protect trees in the interests of amenity. In a conservation area, a tree without an order still needs six weeks' notice to the council before most work to it (section 211). See living in a conservation area.

Two-stage tender

A tender in which a contractor is chosen on a first-stage price, then helps develop the design under a pre-construction services agreement before submitting a definitive second-stage price. See traditional or design and build.

Variation

A change to the work instructed under the contract, such as an addition, an omission or a change of specification, and valued under the contract's rules. See what a contract administrator does.