Planning Conditions for London Extensions: Discharging Conditions Before Building

Pre-commencement conditions are the most time-critical conditions on a London extension planning approval — they require specific information or action before any work starts on site. Failure to satisfy a pre-commencement condition before starting work is a planning breach that could result in enforcement action and, in the worst case, a requirement to reverse the works. The most common pre-commencement conditions for London extension approvals: Condition: materials to be approved. Wording example: 'Before development commences, samples of the external materials to be used in the construction of the extension shall be submitted to and approved in writing by the local planning authority.' What it requires: physically submitting samples of the proposed external materials (facing brick, mortar, render colour, window frame specification, roof covering material) to the London Borough's planning department for written approval before any groundworks or structural works begin. How to discharge it: submit an application to discharge the condition through the Planning Portal (online) — attaching photos and specifications of the proposed materials, and physically delivering samples to the Borough's planning offices if required. Application fee for discharging a pre-commencement condition: £34 per condition (as of April 2025). Timeline: most London Boroughs determine condition discharge applications within 6-8 weeks, though complex conditions in conservation areas may take longer. Condition: Construction Method Statement (CMS) or Construction Management Plan (CMP). Wording example: 'Before development commences, a Construction Method Statement shall be submitted to and approved in writing by the local planning authority.' What it requires: a document describing how the construction works will be managed — including site access and parking for construction vehicles, delivery hours, dust and noise mitigation, working hours, hoarding provisions, and neighbour communication. How to discharge it: prepare a CMS document (typically 2-6 pages) and submit through the Planning Portal. The contractor or principal contractor typically prepares the CMS. Condition: archaeological investigation. What it requires: where an archaeological desk-based assessment or evaluation trench investigation is required (typically in areas of London with known archaeological sensitivity — the City of London, parts of south London with medieval remains, etc.), the investigation must be completed and reported to the planning department before groundworks begin.

Material conditions (conditions relating to the physical materials, details, and specification of the proposed development) are the most commonly attached conditions on London extension approvals — particularly in conservation areas. Understanding what each type of material condition requires: Facing brick matching condition: 'The external facing brick to the extension shall match the existing brick to the host property in type, colour, texture, and coursing bond.' What it means: the new facing brick for the extension must visually match the existing Victorian brick of the terrace. In London, matching Victorian stock brick (the yellow-buff colour of London stock) can be difficult — Victorian brick is no longer in production. Approved sources for matching London stock brick: reclaimed stock brick suppliers (South London Stock, Michelmersh Brick — who produce new-manufacture London Stock brick colours that closely approximate the original); sample testing by submitting a small panel of each candidate brick to the planning officer for comparison with the existing brick. Render colour and texture condition: 'The render finish to the extension shall match the existing render to the property in colour, texture, and profile.' What it requires: specifying the exact render product, colour reference, and texture (fine scratch, medium scratch, smooth) and submitting this for planning officer approval. Roof material condition: 'The roof covering of the extension shall be natural Welsh slate matching the natural slate to the existing main roof.' What it requires: specifying the exact slate source (Welsh natural slate from the Penrhyn, Ffestiniog, or Cambrian Belt quarries is typically specified for a London Victorian terrace in a conservation area) and confirming coverage, coursing, and fixing method. Window design condition: 'The windows to the extension shall be in the design, materials, and finish shown on drawing [reference]' or 'windows shall be timber-framed in a design to complement the existing sash windows.' What it requires: confirming the exact window specification — frame material (timber or slim aluminium), opening type (casement, top-hung, tilt-turn), frame colour, and whether opening lights are required — against the approved drawings.

Hours of work conditions are frequently attached to London extension planning approvals to protect neighbouring residential properties from excessive noise and disturbance during construction. Standard hours of work condition for London extension approvals: 'The development hereby permitted shall only be carried out between the hours of 08:00 and 18:00 on Monday to Friday, between 08:00 and 13:00 on Saturdays, and not at all on Sundays, Bank Holidays, or Public Holidays.' These are the most commonly imposed working hour restrictions in London. Some Boroughs (particularly inner-London Boroughs with dense residential neighbourhoods) impose stricter hours — for example, 08:30-17:30 Monday to Friday and 08:30-13:00 Saturday in some Islington and Camden conservation areas. What contractors need to do: follow the approved working hours strictly; no early deliveries (lorry engines running outside permitted hours); no early site activity (concrete pumping, heavy plant operation) before 08:00. Party wall or neighbourly conditions: some London Boroughs attach conditions requiring specific protection of neighbouring properties during construction — for example: all excavation work within 3m of the party wall shall be carried out in discrete sections and backfilled before the next section commences; scaffolding fixed to the party wall shall be removed within 14 days of completion of the works; water management conditions: all surface water from the building works shall be managed on site and not discharged to the public highway. These conditions are typically designed to respond to specific site constraints or concerns raised during the consultation on the planning application.

Not all conditions must be discharged before starting work — some conditions are satisfied during construction or before the extension is occupied: During construction conditions: sample panels: 'A sample panel of the facing brick, measuring no less than 1m x 1m, shall be erected on the site for the approval in writing of the local planning authority before any brickwork commences.' What this means: even where a material condition has been discharged (the brick type and mortar colour approved on paper), the planning officer may require a physical panel to be erected on site for inspection before full-scale brickwork proceeds. The sample panel must be approved before brickwork above the DPC course commences. Party wall condition compliance: where a party wall award has been made under the Party Wall Act, the works must comply with the award's provisions throughout construction — the party wall surveyor may conduct inspection visits during construction. Pre-occupation conditions: completion of landscaping: 'No part of the development shall be occupied until the hard and soft landscaping scheme shown on drawing [reference] has been completed in full.' Completion of boundary treatment: 'No part of the development shall be occupied until the boundary fences/walls shown on drawing [reference] have been erected.' Compliance certificate: 'No part of the development shall be occupied until a compliance certificate for the drainage/structural/electrical works has been obtained from the relevant authority.' How to discharge conditions during or after construction: apply through the Planning Portal at the appropriate stage of construction, submitting the required evidence (photos, certificates, specifications, test reports). A pre-occupation condition cannot be discharged until the work is complete — but planning ahead ensures that the completion certificate is not delayed.

Starting work before pre-commencement conditions are discharged, or failing to comply with attached conditions during or after construction, is a planning enforcement matter. The consequences of breaching planning conditions in London: Planning enforcement notice: the London Borough's planning enforcement team can issue a planning enforcement notice requiring the breach to be remedied — this may include requiring works to be reversed (undone) or modified to comply with the condition. Where the works have been built in breach of a materials condition (for example, facing brick that does not match the approved specification), the enforcement notice may require the non-compliant facing brick to be removed and replaced — a very expensive remediation. Breach of condition notice: for a simple failure to comply with an ongoing condition (for example, working outside permitted hours), a breach of condition notice can be served — this is a criminal offence and can result in a fine. Impact on future planning applications: a history of planning enforcement action on a property can affect future planning applications — the planning officer may apply more scrutiny and may attach more conditions to future approvals. Invalid planning permission: in the most serious cases, starting development before a pre-commencement condition is discharged may mean the planning permission is never lawfully commenced — making the entire development unauthorised. The safest approach: always check which conditions are pre-commencement; discharge all pre-commencement conditions and receive written confirmation from the Borough before any work starts on site; retain all written correspondence with the Borough's planning department as evidence of condition discharge.