Planning & Permissions
in Westminster, SW1
Architects, Engineers, Surveyors & Builders Under One Roof.
Hampstead Chartered Surveyors & Building ConsultancyOne Studio. One Contract. One Team.
We coordinate Westminster planning & permissions with planning-aware designers, surveyors and technical specialists under one accountable studio - feasibility, measured surveys, drawings, visual material, heritage constraints, submission strategy, consultant coordination and build-ready handover through one managed process.
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Planning & Permissions in Westminster: What You Need to Know
Every planning project in Westminster is designed to respect the Smith Square / Westminster Conservation Area and the character of Georgian townhouses, listed Westminster terraces, Crown Estate mansion flats. Our in-house architects, designers and structural engineers handle Westminster planning applications, our structural engineers specify any load-bearing work, and our directly-employed trades deliver the build under one fixed-price contract. We coordinate Building Control, Party Wall awards where needed, and all certifications through to handover.
Political heart of London with residential pockets around Smith Square, Lord North Street, and Vincent Square. Westminster conservation area with significant listed buildings. Our planning consultants have extensive experience with Westminster applications, including householder planning, full planning, Listed Building Consent, and lawful development certificates. We handle pre-application discussions and manage the entire submission process.
We prepare Westminster applications with pre-application research and a design and access statement written for Westminster's conservation and listed building policies, and we keep the case officer informed until a decision is issued.
Planning & Permissions
Navigating London's planning system is half the battle of any building project. Our in-house architects, designers and structural engineers and dedicated planning consultants manage every application type — from straightforward permitted development confirmations to complex conservation area submissions and listed building consent — across every inner London borough.
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Planning Expertise for London's Most Challenging Boroughs
London's planning landscape is among the most complex in the world. Thirty-two boroughs, each with their own local plan, supplementary planning documents, conservation area appraisals and design guidance. Layer on top of that permitted development rights (which vary by property type, area designation and previous permissions), Article 4 directions that remove PD rights entirely, conservation area restrictions, listed building requirements and the increasingly common demand for Basement Impact Assessments, and even a simple rear extension can become a planning maze.
Our planning success comes from two things: first, our in-house architects, designers and structural engineers design schemes that are inherently approvable — they understand the massing, materials, detailing and proportions that planning officers and conservation officers want to see. Second, our dedicated planning consultants know how each borough interprets its policies, which arguments work and which don't, and when to push for a more ambitious scheme versus when to stay within safer parameters.
We offer planning services both as part of our integrated design-and-build package (where planning is included in the project fee) and as a standalone consultancy for clients who have their own builder. Either way, you get the same team and the same rigour.
Every Route Through London's Planning System
We handle every type of planning application and consent that residential projects in London require.
Permitted Development
Confirming that your proposed works fall within PD rights — including the larger home extension scheme (prior approval), rear and side extensions, loft conversions and outbuildings. We apply for a Lawful Development Certificate (LDC) to provide formal legal confirmation that no planning permission is needed.
View Details →Depends on the evidence neededHouseholder Planning
Full planning applications for extensions, loft conversions and alterations that fall outside permitted development — including double-storey extensions, side extensions on corner plots, properties with Article 4 restrictions and proposals that exceed PD size limits. We prepare plans, elevations, design and access statements and manage the application through to decision.
Scaled to the drawings requiredConservation Area Applications
Design-sensitive submissions for properties within conservation areas, where materials, proportions, roof forms and the relationship to neighbouring buildings are scrutinised by conservation officers. We attend pre-application meetings, negotiate design amendments and produce heritage impact statements where required.
View Details →Reflects the heritage inputListed Building Consent
Separate consent required for any works affecting the character of a listed building — internal or external. We prepare detailed method statements describing every proposed alteration, justifying the works in heritage terms and demonstrating how the building's significance is preserved or enhanced. LBC runs in parallel with planning permission where both are required.
View Details →Depends on the listed fabric affectedBasement Impact Assessment
Most London boroughs now require a BIA for basement excavations — covering hydrology, structural methodology, construction management, soil disposal logistics, vibration assessment and monitoring strategy. We commission the geotechnical investigations, prepare the full BIA document and manage it through to discharge of pre-commencement conditions.
Driven by the site investigationsDischarge of Conditions
Many planning approvals come with conditions that must be formally discharged before or during construction — materials approval, landscaping schemes, construction management plans, drainage details and more. We manage every condition application, ensuring nothing delays the build programme or risks a breach of planning consent.
Depends on the number of conditionsFrom First Assessment to Approved Plans
A rigorous process that maximises approval probability while protecting your design ambition.
Planning Assessment
We review your property against the relevant planning policies — checking PD rights, conservation area status, Article 4 directions, tree preservation orders and any existing planning history. You receive a clear written assessment identifying the correct application route, likely timescale, key risks and our recommendation on the best approach. This is without obligation for all enquiries.
Design & Pre-Application
Our architects design the scheme — plans, elevations, sections and 3D visuals that show exactly what's proposed. For complex or sensitive sites, we submit a pre-application enquiry to the local authority, meeting with the case officer (and conservation officer, where applicable) to discuss the proposals before making a formal submission. Pre-apps cost extra but significantly de-risk larger projects by identifying objections early.
Application Submission
We prepare the complete submission package — application forms, site and location plans, proposed drawings, design and access statement, heritage statement (where applicable), BIA (for basements), CIL forms and any specialist reports. We submit via the Planning Portal, pay the application fee on your behalf and confirm validation with the borough. You receive a copy of the full submission for your records.
Management & Determination
During the 8-week determination period, we monitor the application, respond to any case officer queries, address neighbour objections with reasoned planning arguments, negotiate minor amendments if requested by the officer and maintain communication with the planning department until a decision is issued. If approval is granted with conditions, we advise which conditions need discharging before construction and manage those applications in sequence.
Transparent Pricing
Guide prices for standalone planning services. For design-and-build clients, planning is included within the project fee at no additional cost.
Lawful Development Certificate
Formal confirmation that your works fall within permitted development rights. Provides legal certainty and protects you on future sale.
Householder Application
Full planning application for extensions and alterations outside PD. Includes drawings, D&A statement and full application management through to decision.
Conservation Area
Design-sensitive application within a conservation area. Includes heritage statement, pre-application meeting and conservation officer negotiation.
Listed Building Consent
Detailed consent application for works affecting a listed building's character. Includes method statements, heritage impact assessment and officer meetings.
Why Our Planning Approach Works
What separates our approach from a planning consultant who has never held a trowel.
Design-Led Submissions
Our planning applications are prepared by in-house architects, designers and structural engineers who design the scheme — not planning consultants who write reports about someone else's design. The drawings are better, the proportions are right and the design narrative is compelling because the designer and the applicant are the same person.
Borough-by-Borough Knowledge
We read each scheme against the policies of the council that will decide it before we draw a line.
Buildable Designs, Not Just Approvable
Because we also build what we design, our planning submissions reflect real-world construction. The beam sizes are correct, the materials are genuinely available, the drainage runs are feasible. This means fewer condition discharge issues and no surprises when building regulations drawings are produced.
Pre-Application Strategy
For sensitive sites, we submit paid pre-application enquiries and attend face-to-face meetings with planning officers — de-risking the formal application by resolving objections before they're raised.
Conservation Officer Liaison
Our architects speak the language of heritage — significance, setting, character, special interest. We build relationships with conservation officers and negotiate design solutions that satisfy both the client and the heritage framework.
Neighbour Management
We advise on pre-submission neighbour consultation where it helps — sharing drawings and addressing concerns before the formal notification period, reducing objections that can delay or complicate applications.
PD Maximisation
We identify every opportunity to use permitted development rights — including the larger home extension scheme, prior approval routes and combinations of PD classes — to avoid the cost and delay of a full planning application where possible.
Condition Discharge
We manage all post-approval condition discharges — materials, landscaping, drainage, construction management and any other pre-commencement conditions — ensuring nothing delays your build start date.
Appeal Support
If an application is refused, we provide clear advice on appeal prospects and prepare written representations or hearing statements for Planning Inspectorate appeals.
CIL & Section 106
We calculate Community Infrastructure Levy liability, advise on self-build exemptions where applicable and manage any Section 106 obligations attached to larger applications.
Standalone or Integrated
We provide planning consultancy as a standalone service to external clients, or as part of our design-and-build offering where planning is included in the project fee at no extra cost.
Do I Need Planning Permission?
The answer depends on what you want to build, your property type and any designations affecting your home. Here is how to work out which route applies.
Permitted Development Rules Summary
Permitted Development (PD) rights allow certain building works to proceed without a formal planning application. For houses (not flats), PD covers single-storey rear extensions (up to 3m attached, 4m detached), loft conversions within volume limits (40m³ terraced, 50m³ others), internal alterations and some changes of use. The rules are set by the Town and Country Planning (General Permitted Development) Order — a national framework that local authorities cannot override except through Article 4 directions.
When you ALWAYS need planning:
Conservation areas with Article 4 directions — PD rights may be wholly or partially removed. Listed buildings — any alteration, internal or external, requires Listed Building Consent in addition to any planning permission. Flats and maisonettes — no PD rights for extensions or loft conversions. New-build properties — PD rights may have been removed as a condition of the original planning consent. Mansard loft conversions — always require full planning. Two-storey extensions exceeding 3m depth — full planning required.
Lawful Development Certificate (LDC): If your works fall within PD, we strongly recommend applying for an LDC. This is formal legal confirmation from the council that your works are lawful. An LDC is invaluable when selling the property — solicitors routinely request proof that works were lawful, and its absence can delay or derail a sale.
Prior Approval route: For larger single-storey rear extensions (4–6m attached, 4–8m detached), a Prior Approval application notifies the council and your neighbours. The council assesses the impact on amenity and decides within 42 days. This is simpler and cheaper than a full planning application but does involve neighbour consultation. We prepare and manage Prior Approval applications as part of our planning service.
London Borough Planning Guide
Every London borough has its own planning culture, policies and priorities. Knowing how each council approaches residential applications is critical to a successful outcome.
Westminster
Some of the strictest planning controls in London, reflecting the exceptional architectural and historic significance of the borough. Almost the entire borough is covered by conservation area designations. Westminster requires exceptionally detailed Design and Access Statements, and officers expect materials to be specified at application stage (not left to condition). Basement policies limit excavation to a single storey and require detailed construction management plans. Pre-application advice is essential for any significant proposal in Westminster.
What If Planning Is Refused?
Understanding the options if an application is refused provides peace of mind.
This is usually the fastest and most cost-effective route. We analyse the refusal reasons, redesign the problematic elements and resubmit with a targeted covering letter explaining how the revised scheme addresses each concern.
Appeal to the Planning Inspectorate
You have the right to appeal a refusal to the Planning Inspectorate — an independent government body that reviews the council's decision. Appeals must be submitted within 12 weeks of the refusal (for householder applications) or 6 months (for other applications). The Inspector considers the original application, the council's reasons for refusal and any representations. The appeal is decided on written representations (no hearing) for most householder cases.
Appeal Costs
There is no fee to appeal to the Planning Inspectorate — it is a free process. However, professional fees for preparing the appeal submission depend on complexity.
Pre-Application Advice
The best way to avoid refusal is to seek pre-application advice from the council before submitting. Most London boroughs offer a paid pre-app service for householder proposals where a planning officer reviews your scheme informally and provides written feedback on likely issues. We handle pre-app submissions for every complex project — the modest fee is invariably cheaper than the cost and delay of a refusal and redesign.
CIL & Section 106
Some residential projects trigger financial contributions to the local authority. Understanding these charges early prevents budget surprises.
Community Infrastructure Levy (CIL)
What is CIL? The Community Infrastructure Levy is a charge that councils levy on new development to fund local infrastructure — schools, transport, parks and community facilities. It is calculated as a fixed rate per square metre of new floor space created. In London, both the borough CIL and the Mayor of London CIL apply, so the total charge is the sum of both.
How to calculate CIL liability: CIL is charged on the net additional floor space created. If you are building a 30 square metre extension, the CIL is calculated on 30 square metres. If you demolish an existing 15 square metre conservatory and build a 30 square metre extension, CIL applies to the net gain of 15 square metres. Rates are set by each borough's own charging schedule, so Westminster's schedule decides the figure for an extension there.
Exemptions: Self-build exemption — if you will occupy the new space as your principal residence for at least 3 years, you can apply for a full CIL exemption before starting work. This is a critical saving that many homeowners miss. Extensions under 100 square metres are exempt from CIL provided the building is in lawful residential use. Affordable housing is also exempt. The exemption must be applied for before work commences — retrospective claims are not accepted.
Section 106 obligations: Section 106 agreements apply to larger projects (typically new homes, conversions creating multiple units or major commercial development) rather than standard house extensions. They are negotiated between the developer and the council to provide site-specific benefits — affordable housing contributions, public realm improvements, employment and training obligations. For most residential extension and loft conversion projects, Section 106 does not apply. However, if you are converting a house into multiple flats, or building a new dwelling in the garden, a Section 106 obligation may be required.
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Planning & Permissions Questions
Common questions about planning in London.
Do I need planning permission for my project?
How long does a planning application take?
What is a Lawful Development Certificate?
What is an Article 4 direction?
What happens if my application is refused?
Do I need planning for a basement conversion?
Can you handle planning for my own builder?
Related Guides & Articles
Popular Guides for Westminster
Use these area-specific guide pages to compare the next build routes, planning questions and cost topics people commonly research in Westminster SW1.
Book a planning assessment
Tell us what you're planning and we'll identify the correct application route, likely timescale and key risks — without obligation. We respond within 24 hours.
Planning Assessment
We review your property, check your PD rights and advise on the best planning route — no cost, no obligation.
Get planning adviceWhy Choose Us for Planning & Permissions in Westminster
We're not a national chain — we're a local design and build practice with deep roots in Westminster and the surrounding neighbourhoods.
Design Studio 25 minutes Away
Our design studio at 250 Finchley Road NW3 is just 25 minutes from Westminster. Visit to see materials, meet the team, and discuss your project in person.
Westminster Planning Experts
Our in-house architects, designers and structural engineers have extensive experience with Westminster Council's planning department, conservation officers, and building control team. We know what gets approved.
We Know Westminster Properties
From the Heritage properties, listed townhouses, mansion blocks and period conversions on Smith Square, Great Peter Street, Marsham Street and Millbank — we understand the specific construction challenges and planning context of every property type in SW1.
Planning & Permissions in Nearby Areas
Read our comprehensive Westminster Planning Guide — conservation areas, permitted development, listed buildings and more.
Planning Near Westminster
The same NW3 design-build team covers the neighbouring areas:
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