Planning Conditions Guide for London Home Extensions in 2025: Pre-Commencement Conditions, Discharge of Conditions, Materials Approval, Tree Protection

Types of planning conditions in London, pre-commencement (condition precedent) conditions, materials approval conditions, and tree protection order conditions for London home extensions in 2025: TYPES OF PLANNING CONDITIONS: planning conditions attached to a HOUSEHOLDER PLANNING PERMISSION for a London home extension are typically organised into the following categories: STANDARD CONDITIONS (applying to all permissions): STANDARD CONDITION 1: works must begin within 3 years of the date of the permission (Town and Country Planning Act 1990 Section 91); STANDARD CONDITION 2: the development must be in accordance with the approved plans (plan reference numbers are listed — it is essential that construction matches the approved plans exactly; any deviation from the approved plans, even a small change, requires a fresh application — either a NON-MATERIAL AMENDMENT or a new full application); PRE-COMMENCEMENT CONDITIONS (CONDITION PRECEDENT): CONDITIONS THAT MUST BE FULLY DISCHARGED BEFORE ANY DEVELOPMENT — ANY WORK, GROUNDWORKS, OR DEMOLITION — BEGINS ON SITE; the most common pre-commencement conditions in London are: MATERIALS CONDITION: the materials to be used in the external walls, roof, windows, and external finishes of the extension must be agreed in writing with the LPA before work begins; the applicant submits a MATERIALS APPLICATION with samples or detailed specifications; ARBORICULTURAL / TREE PROTECTION CONDITION: where a planning application site has TREES (including neighbouring trees whose Root Protection Area extends into the site), the LPA will require: a TREE SURVEY REPORT (BS 5837:2012 — listing all trees on and adjacent to the site: species, height, spread, canopy drip line, Root Protection Area — typically 12× the stem diameter at 1.5m height); an ARBORICULTURAL IMPACT ASSESSMENT (AIA): assessing which trees are affected by the proposed development; an ARBORICULTURAL METHOD STATEMENT (AMS): specifying how the trees will be protected during construction (root protection areas protected by temporary fencing, no materials storage within the RPA, no excavation within the RPA without prior agreement and arboricultural supervision, Aboricultural Site Supervision during critical works phases); this documentation must be submitted to and approved by the LPA's arboricultural officer BEFORE work begins; TREE PROTECTION ORDER (TPO): a TPO is a statutory order protecting a specific tree or group of trees; carrying out works to a TPO tree without consent (pruning, cutting down, topping) is a criminal offence with potential unlimited fine; a PLANNING APPLICATION for any development that may affect a TPO tree must be accompanied by the arboricultural documentation above; the LPA's tree officer will impose conditions protecting the TPO trees; the conditions typically require: TREE PROTECTION FENCING (typically orange Heras-type fencing or green mesh fencing staked and tied securely at the edge of the Root Protection Area) installed BEFORE ANY WORK ON SITE and maintained throughout the construction period; NO MATERIALS, PLANT, EQUIPMENT, OR VEHICLES within the RPAs of protected trees; NO CHANGES TO LEVELS (raising or lowering the ground level within the RPA — even a modest change in ground level over tree roots can cause root anoxia and tree death over several years); ARCHAEOLOGY CONDITION: parts of London (particularly areas with historic significance — Roman, Medieval, Saxon — which in London includes large swathes of the City of London, Southwark, Lambeth, and other areas with known archaeological potential) may have an ARCHAEOLOGY CONDITION attached to planning permission; the typical archaeology condition requires: DESK-BASED ASSESSMENT (DBA): a research-based assessment of the archaeological potential of the site, carried out by an accredited archaeologist, and agreed with the LPA's archaeology officer before work begins; ARCHAEOLOGICAL WATCHING BRIEF: an archaeologist must be on site to monitor any groundworks (foundation excavations, drain trenches, ground-slab break-outs) and must be given the opportunity to record and sample any archaeological deposits revealed; this is particularly relevant for DEEPER EXCAVATIONS (basement construction, deep drain trenches) in archaeologically sensitive areas; DESIGN-RELATED CONDITIONS: DETAILS OF EXTERNAL FINISHES: beyond materials approval, some LPAs also require approval of specific design details before they are built (e.g., the design of a parapet coping, a window reveal detail, or a rooflight design); CONSTRUCTION MANAGEMENT PLAN (CMP): for larger projects in constrained London streets (narrow streets, controlled parking zones, or near schools), the LPA may require a CMP to be agreed before work begins — setting out: delivery times (restricted in some London streets), site hoarding and scaffolding arrangements, wheel-wash provision, dust suppression, traffic management, parking for workers, noise hours; ECOLOGY CONDITION: where the property or its outbuildings may provide habitat for BATS (a European Protected Species — any damage to a bat roost is a criminal offence), the LPA may require a BAT SURVEY (PRELIMINARY ROOST ASSESSMENT — PRA) and, if bats are found, a BAT MITIGATION LICENCE from Natural England before works affecting the roost can proceed; CONDITION TIMESCALES FOR SUBMISSION AND DISCHARGE IN LONDON: the applicant submits an APPLICATION TO DISCHARGE A PLANNING CONDITION (using the LPA's online planning portal — e.g., the Planning Portal at planningportal.co.uk for England); FEE FOR DISCHARGING CONDITIONS (as of 2025): approximately £34 per condition request (for householder applications); the LPA has 8 WEEKS to approve the condition discharge; in practice in London: 4-10 weeks is typical; IMPORTANT: the approval must be IN WRITING — a verbal assurance from the planning officer that the materials are fine is NOT sufficient; always get written (email or formal decision letter) approval before commencing work.

How to apply to discharge planning conditions, construction management plans, non-material amendments to approved plans, and the legal and practical risks of starting work before planning conditions are discharged for London home extensions in 2025: HOW TO DISCHARGE A PLANNING CONDITION — THE STEP-BY-STEP PROCESS: STEP 1 — READ ALL CONDITIONS ON THE PERMISSION CAREFULLY: the planning decision notice lists all conditions; read every condition and identify which are: INFORMATIVE ONLY (no action required); POST-COMMENCEMENT (compliance required during or after construction — e.g., windows must match approved material schedule throughout the works); PRE-COMMENCEMENT (CONDITION PRECEDENT) — MUST be discharged before ANY work starts; STEP 2 — PREPARE THE REQUIRED INFORMATION FOR EACH PRE-COMMENCEMENT CONDITION: for a MATERIALS CONDITION: prepare a MATERIALS SCHEDULE listing the specific products to be used: EXTERNAL WALLS: e.g., facing brick — Ibstock Luton Yellow Stock to match existing; ROOF: e.g., standing seam zinc or EPDM flat roof with pea gravel ballast; WINDOWS: e.g., thermally broken aluminium windows, powder-coated RAL 7016 Anthracite Grey; DOORS: e.g., aluminium bifold doors, matching window colour; if the property is in a Conservation Area: the LPA may require PHYSICAL SAMPLES to be submitted to the planning office and agreed in writing — mortar samples, brick samples, and tile samples are often required; for an ARBORICULTURAL CONDITION: engage an ARBORICULTURALIST (member of the Arboricultural Association — search arboriculture.org.uk) to prepare the TREE SURVEY REPORT (BS 5837:2012), ARBORICULTURAL IMPACT ASSESSMENT, and ARBORICULTURAL METHOD STATEMENT; ensure the survey covers ALL TREES (including NEIGHBOURS' TREES with crowns or roots extending into the site — these must be included even if they are on neighbouring land); for a CONSTRUCTION MANAGEMENT PLAN CONDITION: prepare the CMP document setting out: site working hours (typical LPA requirement: 07:30-18:00 Monday to Friday, 08:00-13:00 Saturday, no working Sundays or Bank Holidays); delivery times; parking for trades and delivery vehicles; scaffold and hoarding arrangements; dust suppression; waste management; details may seem bureaucratic but failure to comply with the approved CMP during construction can result in a BREACH OF CONDITION NOTICE from the LPA (a formal enforcement measure); STEP 3 — SUBMIT THE CONDITION DISCHARGE APPLICATION: submit via the PLANNING PORTAL (planningportal.co.uk) or the LPA's own online system; REFERENCE THE CORRECT PLANNING PERMISSION NUMBER; REFERENCE THE SPECIFIC CONDITION(S) BEING DISCHARGED; attach all supporting documents; pay the fee (approximately £34 per condition request in 2025); STEP 4 — WAIT FOR THE LPA'S WRITTEN DECISION: DO NOT COMMENCE WORK BEFORE RECEIVING THE WRITTEN DECISION; if the condition requires further information (an UNREASONABLE CONDITION or poorly specified condition), the planning officer may request additional detail — provide it promptly; follow up with the case officer if you have not received a decision within 8 weeks; a DEEMED DISCHARGE applies after 8 weeks if the LPA fails to determine the application — but in practice, deemed discharge does not apply to PRE-COMMENCEMENT CONDITIONS under standard Section 74A TCPA provisions; always confirm the position with the planning officer rather than assuming deemed discharge applies; STEP 5 — COMMENCE WORK ONLY AFTER WRITTEN APPROVAL: keep the written approval with your planning permission documentation on site and accessible to the Building Control inspector; the conditions form part of the planning permission — non-compliance is a breach of planning law; NON-MATERIAL AMENDMENTS TO APPROVED PLANS: after receiving planning permission, if the design changes (even slightly — a window moved 200mm, a roof changed from flat to pitched) and the change is more than truly TRIVIAL: a NON-MATERIAL AMENDMENT (NMA) APPLICATION must be submitted to the LPA before the changed element is built; FEE: no fee for NMA (as of 2025 — verify at the LPA); PROCESSING TIME: typically 4-6 weeks; WHAT IS NON-MATERIAL: small changes that do not affect the principle of development, neighbouring amenity, or heritage; specific examples: reducing the size of an extension slightly; relocating a window by a small amount; changing a window from fixed to openable; WHAT IS NOT NON-MATERIAL: a change that affects the relationship of the extension to neighbouring windows (daylight/privacy impact); a change that increases the size or height of the extension; a change that involves a different roof form; a change in facing materials (this is covered by a materials condition — apply to discharge the condition with the new material, not an NMA); SECTION 73 APPLICATION (to vary a condition or amend approved plans more significantly): if the proposed change is material (significantly different from the approved scheme), a new application under Section 73 of the TCPA 1990 is required — to vary a condition to allow the amended design; fee: approximately £258 (householder 2025); RISKS OF STARTING WORK BEFORE PRE-COMMENCEMENT CONDITIONS ARE DISCHARGED: this is a VERY SERIOUS LEGAL RISK in London: the LPA can serve a STOP NOTICE (requiring all work to stop immediately — failure to comply is a criminal offence); the LPA can serve a BREACH OF CONDITION NOTICE (requiring compliance within a specified period, after which the LPA can itself carry out the works and recover the cost from the landowner); the LPA can treat the PLANNING PERMISSION AS NULL AND VOID (where a pre-commencement condition precedent has not been met — the permission never became operative); in the worst case, the LPA can require DEMOLITION of any work carried out without valid permission; the property CANNOT be SOLD with planning enforcement outstanding — the standard pre-exchange solicitor's enquiry (Con29 search) will reveal any enforcement notice; a property with live planning enforcement action is very difficult to mortgage and may be unsaleable until the enforcement is resolved; PRACTICAL ADVICE FOR LONDON HOMEOWNERS: READ THE DECISION NOTICE BEFORE INSTRUCTING A CONTRACTOR; identify all pre-commencement conditions; submit the discharge applications as early as possible after receiving the permission (even before contractor procurement — the typical 4-8 week discharge timeline can run in parallel with the contractor procurement and contract stage); ensure the contractor is aware of the conditions and does not start work until all pre-commencement conditions are approved in writing; keep copies of all condition discharge approvals on site during construction.