Pre-application Advice: Is It Worth the Fee?

Before submitting a planning application for a home extension, conversion, or new build in the Hampstead area, you have the option to seek pre-application advice from the local planning authority. This is a paid service where you present your proposals to a planning officer and receive an informal assessment of whether they are likely to be supported. For some projects it is invaluable; for others it is an unnecessary expense. This guide explains how the process works in Camden and Barnet, what it costs, and how to decide whether it is worth the fee for your project.

What Is Pre-application Advice?

Pre-application advice (commonly called "pre-app") is a service offered by most local planning authorities in England. You submit details of a proposed development before making a formal planning application, and a planning officer reviews the proposals against relevant planning policies. They then provide a written response setting out their view on the acceptability of the scheme and highlighting any issues you should address.

The service is entirely voluntary. There is no legal requirement to seek pre-app advice before submitting a planning application. But for complex or sensitive projects, it can significantly improve your chances of getting planning permission — and reduce the time and cost of the formal application process.

What Camden and Barnet Offer

Both Camden Council and the London Borough of Barnet operate tiered pre-application services, with fees and levels of engagement scaled to the size of the proposed development.

Camden's pre-application service for householder developments (extensions, loft conversions, and similar residential alterations) offers a written response from a planning officer based on submitted drawings and supporting information. For larger or more complex residential schemes — such as flat conversions, new-build houses, or basement developments — Camden offers meetings with the case officer and potentially a Design Review Panel for the most significant proposals.

Barnet's service is structured similarly, with different fee bands for householder, minor, and major development proposals. Barnet also offers a duty planner service for quick, free initial queries, which can help you gauge whether a more formal pre-app is necessary.

Both authorities publish their pre-application fee schedules on their websites, and these are updated periodically. Fees are non-refundable and must be paid before the enquiry is processed.

How Much Does It Cost?

Pre-application fees vary depending on the scale of the proposal. As a general guide for residential projects in north London:

• Householder proposals (extensions, loft conversions): £200–£600 for a written officer response
• Minor residential development (one to nine new dwellings, flat conversions): £1,000–£3,000, often including a meeting with the case officer
• Major residential development (ten or more dwellings): £3,000–£10,000+, potentially including multiple meetings and Design Review Panel input

These are indicative ranges. Camden tends to sit at the higher end. Barnet's fees are generally slightly lower but have been increasing. Always check the current fee schedule directly with the relevant authority before budgeting.

For a typical homeowner in Hampstead planning a rear extension or loft conversion, the pre-app fee is measured in hundreds of pounds. For an investor planning a flat conversion or new-build scheme, it rises into the low thousands. Against the overall cost of the project and the formal planning application fee, this is usually a modest outlay.

What to Submit

The quality of the response you receive depends directly on the quality of what you submit. A vague sketch on the back of an envelope will get a vague response. A well-prepared submission will elicit a detailed, useful officer assessment.

Your pre-application submission should ideally include:

• A completed pre-application form (each authority has its own)
• A covering letter setting out the proposal, the planning history of the site, and the key issues you want the officer to address
• Existing and proposed floor plans, elevations, and a site plan, drawn to scale by your architect
• Photographs of the site and its context
• A brief planning statement explaining how the proposal complies with relevant policies
• Any specialist reports that are already available (for example, a heritage statement if the property is listed or in a conservation area)

The more resolved the drawings and the clearer the planning justification, the more specific and useful the officer's response will be. This is where having an architect prepare the pre-app submission pays for itself — they will present the scheme in the language and format that planning officers expect and will frame the questions to draw out the most useful guidance.

Officer Response and Turnaround

Camden aims to provide written pre-application responses within six to eight weeks for householder proposals. For more complex schemes involving meetings, the process can take eight to twelve weeks. Barnet's turnaround times are broadly similar, though both authorities occasionally experience backlogs that extend these timescales.

The response will typically cover:

• Whether the principle of development is acceptable
• The officer's view on the design, scale, and massing of the proposal
• Any likely impacts on neighbouring amenity (overlooking, loss of light, overbearing impact)
• Whether the proposal is consistent with conservation area or listed building policies
• Any specific policy requirements you will need to address (for example, CIL liability, affordable housing, sustainability standards)
• A recommendation on whether to proceed to a formal application, and any changes the officer suggests

The response is usually a written letter, sometimes accompanied by annotated drawings. For larger schemes involving meetings, you will also receive notes of the meeting discussion.

How Much Weight Does Pre-app Advice Carry?

This is the critical question, and the answer requires some nuance. Pre-application advice is informal and is not binding on the council. A positive pre-app response does not guarantee planning permission, and a negative one does not prevent you from submitting an application.

However, in practice, pre-app advice carries significant weight. The officer providing the advice is usually the same person — or at least from the same team — who will determine the formal application. If they have flagged a concern at pre-app stage and you submit the application without addressing it, refusal is likely.

Conversely, if the pre-app response is positive and you submit an application that faithfully reflects the pre-app scheme, you can expect a smooth process. If the application is then determined by a different officer or goes to a planning committee, the positive pre-app response is a material consideration in your favour.

The key caveat is that pre-app advice is based on the information available at the time. If material circumstances change — new planning policies come into force, new information about the site emerges, or third-party objections raise genuine planning concerns — the formal determination may differ from the pre-app advice.

When Pre-app Advice Is Most Valuable

Pre-application advice offers the best return on investment when:

• The proposal is in a conservation area or involves a listed building. Heritage-sensitive sites are where planning outcomes are hardest to predict, and a pre-app discussion with the conservation officer is extremely valuable.
• The proposal is for a new dwelling, flat conversion, or change of use. These applications involve a broader range of policy considerations than a simple extension and are more likely to receive objections.
• You are uncertain about a specific design element. If the success of your project hinges on whether a particular roof design, rear extension depth, or basement is acceptable, the pre-app is the place to test it.
• There is relevant recent planning history. If a previous application on the site was refused, a pre-app allows you to present a revised scheme and gauge whether the changes go far enough.

When to Skip It

Pre-application advice is less useful — and may not be worth the fee — when:

• The proposal is straightforward and clearly policy-compliant. A single-storey rear extension within permitted development parameters, or a loft conversion with a rear dormer on a property where neighbouring houses have already done the same thing, is unlikely to benefit from pre-app advice.
• Time is the priority. If you need to submit a planning application quickly, the six-to-eight-week pre-app turnaround may not be practical. You might be better served by having your architect assess the proposal's compliance against policy and submitting a well-prepared application directly.
• The council's policies give a clear answer. Some planning questions are objectively answerable by reading the development plan and relevant supplementary guidance. If the policy position is clear-cut, paying for a pre-app will only tell you what you already know.

Making the Decision

Discuss the pre-app question with your architect at the start of the project. An experienced architect who works regularly in Camden or Barnet will have a good sense of when pre-app advice is likely to add value and when it is an unnecessary delay. In borderline cases, the cost of the pre-app is usually modest compared to the cost of a refused planning application and a subsequent resubmission. Our service can connect you with architects who have established working relationships with north London planning authorities and can advise you on the best strategy for your specific project.