Planning Appraisals

The choice of achieving your extension with a certificate of lawfulness or going down the route of a planning application, may affect the size of the extension.

You may want to accommodate a growing family or to allow an elderly relative to live with the family and that’s why you are considering an extension or alteration – a good alternative to moving completely. Consider that you may need a planning appraisal.

A planning appraisal is an assessment of a site regarding its planning potential and the reason for the proposed development. There may be specific size requirements for an extension (to be able to accommodate a particular make and model of kitchen or a bathroom, for example). The internal size requirements will dictate how large the extension will need to be.


All of these considerations will be taken into account in the planning appraisal.

What is an Appraisal used specifically for?

An appraisal may be used as an assessment of a site to identify the planning opportunities. As well as smaller sites – for example, a single residential plot – appraisals may be used for larger, undeveloped sites or perhaps an under- developed site that can accommodate more development.

A planning appraisal will reveal the planning history of a site – the applications that have been made there previously (or on a neighbouring site) and the lawful planning use of the site. The history of a site is very important in planning terms as it can dictate what the Local Planning Authority may find acceptable for it.

What should it include?

An appraisal should include an assessment of the planning policy framework surrounding a site and the planning constraints for the site. Whether there are any restrictive planning designations or conditions on a site which may limit the extent of any potential development there would be revealed by an appraisal. A planning appraisal is often the first step in considering an extension or a development project before seeking the opinion of the Local Planning Authority.

Planning appraisal

  1. Identify the site
  2. Know the purpose of the proposed extension/ works
  3. Identify the planning constraints surrounding the site
  4. Indentify the planning policies relevant to the site
  5. Explore the history of the site
  6. Apply your findings to the site in order to ascertain the parameters of what may be acceptable on it in planning terms

What is a Pre-Application Submission?

A pre-application submission to a Local Planning Authority (LPA) is an enquiry to the LPA seeking an opinion on the potential acceptability of a proposed development. This is a service for which a fee is payable; the fee varies between authorities (and the level of service requested – see below). It is important to note that the reply would only be an informal opinion of the LPA concerning the proposal. Depending on the level of service requested, the response from the LPA would inform whether the proposed development requires formal planning permission or not and if permission is required, whether the proposal may be considered acceptable by the LPA or not.

Preparing for a Pre- Application Submission

A pre- application submission must include a plan of the existing property and the proposed extension.  It must include sufficient detail to enable the LPA to be able to understand what is being proposed. The plan should be accompanied by a covering letter with an explanation of the proposed extension (and, if appropriate, an explanation of the how the proposal complies with policy). Many LPAs will require an application form to be filled in for such an enquiry and in most cases this may be done on line, attaching the plan of the proposed extension and the covering letter.

Most LPAs offer a service whereby they only advise whether permission for the proposal is required or not or, if it is required, the potential acceptability of the proposal. In order to advise on the potential acceptability, a site visit would be required: the fee for this service is greater than for just advising on the need for permission. In advising on the need for planning permission, the LPA would need to assess the size of the proposed extension, whereabouts on the house (or commercial building) the extension is proposed and the history of the property.

Having considered the relevant details and history, the LPA would reply with a letter.

Is Planning Permission required or not?

The advantage of a pre- application submission is that it allows the property owner to know whether a proposed extension requires permission or not and if it does, its potential acceptability. This may save time and expense in not submitting a planning application where one is not required or may avoid the need for potential enforcement action if work is started on an extension where planning permission is required but was not sought.  Keep in mind – the written response from the LPA would only be an informal response, caveated as such.

If the advice provided by the LPA is that permission would not be required for the proposed extension, it would be advisable to apply for what is known as a certificate of lawfulness for the proposed development. If the advice is that the proposed extension does require planning permission, it would be necessary to apply for planning permission for the proposal.


While it is not necessary to apply for a certificate of lawfulness for a proposed extension, it is advisable to do so in order to be able to demonstrate to the LPA that the proposed extension does not require planning permission as and when the works for the extension start.

When the property is sold, the purchaser’s solicitor will require evidence that any works to the property that did not receive planning permission, did not require it. A certificate of lawfulness will demonstrate this.

Pre-application submission

  1. Identify the site
  2. Identify the desired development
  3. Prepare plans for the proposed development
  4. Consider the planning framework surrounding the site and the proposal and draft a pre- application submission statement
  5. Submit the documents

Preparing for a Submission of a Certificate of Lawfulness or a Planning Application

Establishing whether an extension requires planning permission or not, and which form of application is required, it will be necessary to apply for that application.

A certificate of lawfulness is a legal determination as to whether an extension requires planning permission or not. The details of the proposed extension would be compared against the relevant section of the Town and Country Planning (General Permitted Development) (England) Order 2015 to ascertain this. A planning application is a formal application for planning permission. Both forms of application need to be submitted to the Local Planning Authority (LPA).

In both cases, existing and proposed plans and elevations of the development must be submitted along with a block plan and a site location plan of the site. The plans and elevations must provide a clear picture of the proposed extension (or outbuilding) and whereabouts on the dwelling or property it is proposed. The plans must be submitted with the relevant completed and signed application forms.

In the case of an application for a certificate of lawfulness, a Planning Statement should be submitted with the application describing why the proposal may be viewed as being permitted development and why it complies with the relevant class or classes of the Town and Country Planning (General Permitted Development) (England) Order.      

In the case of a planning application, a Design and Access Statement should be submitted with the application describing and explaining why the proposed development complies with local and national planning policy and why it is acceptable in planning terms.

Certificate of lawfulness or planning application
Identify the site

  1. Identify the desired development
  2. Prepare plans for the proposed development
  3. Consider the planning framework surrounding the site and the proposal and draft the statement for the application
  4. Submit the documents

The Planning Process

From the moment a planning application has been registered and allocated to a Planning Officer, the 8-week application time period countdown starts. As certificates of lawfulness are applications seeking an opinion of whether planning permission is required or not, the neighbouring properties are not notified by the Local Planning Authority about the application. However, neighbours are notified of householder and full planning applications and are given three weeks in which to make any comments about the proposed development, should they so wish (either by letter or e mail).

Planning applications are also advertised by site notice (and an advertisement in the local newspaper), though the rules surrounding which applications are notified in these ways vary between different authorities. Site notices must be displayed for three weeks and newspaper advertisements also run for three weeks.

During the course of the 8 week application period, the Case Officer assigned the application will usually make a site visit as part of the planning process. The plans that were submitted as part of the application will be assessed against the property and checked for their accuracy.

During the site visit, the Case Officer will make an initial assessment of the acceptability of the proposal.

Once the three week neighbour notification period (and the three weeks for site notice and newspaper advertisement, as required) have elapsed (they run concurrently), the Case Officer is able to draft a report about the application recommending approval or refusal for the proposed development, as appropriate. If there are concerns with the proposed development as submitted, amended plans may be sought to overcome the concerns. However, different LPAs have different rules as to whether amended plans may be sought or not.

Once the Case Officer has drafted their report about the application and the notification period has expired, the report may be passed across to the Team Leader or Development Manager for signing off. Once signed off, the decision may be issued.

Planning Appeals

 “If a planning application is refused, there is the right to appeal the refusal”

The appeal is made to the Planning Inspectorate and involves the submission of a statement rebutting the reason(s) for refusal of the application. The statement should break down the refusal and address each part of the refusal. An appeal may also be made if the Local Planning Authority has not made a decision on the application in the time limit for an application. In the majority of applications (including householder applications and certificates of lawfulness), the limit is 8 weeks.  

There are three routes (or procedures) an appeal may take –

  • Written representations
  • Hearings
  • Public inquiries.

The Planning Inspectorate chooses the type of appeal in each case. Most appeals are dealt with by the written representation procedure – this is the easiest and quickest route for an appeal to follow and the one almost always used for householder applications and certificates of lawfulness.

Upon submission of the appeal and once registered as valid, the appropriate procedure is determined, and the appeal is allocated to a Planning Inspector. The appellant or Planning Consultant and the LPA will be notified of the procedure, the appeal start date, the appeal reference number and the timetable for the appeal.  In the majority of appeals, the Inspector will make a site visit and if the site of the extension may be viewed from public land (for example, if it is a front extension), the site visit will be an unaccompanied one. If the Inspector has to go on to the site in order to make the appeal (for example, if the proposal is a rear extension), the site visit will be an accompanied visit and the Inspector will be met by the appellant (or consultant) and a representative of the LPA.  

As part of the appeal, the documents submitted with the planning application to the Council will be considered by the Inspector, as will the relevant local and national planning policies, and any other matters relevant to the appeal. As well as the stated reason(s) for refusal, the Inspector will consider all of the planning issues pertinent to the appeal in reaching their decision. The decision on the appeal is usually issued around 6 – 8 weeks after the site visit. 

The Step-by-Step Guide to a Complete Planning Consultancy Service

A complete planning consultancy service is able to advise on the need for planning permission for a particular project and manage all stages of the process. This would include the following.


1. Initial discussions – size and scale of an extension or project.


2. Initial plan preparation, client discussions / amendments as necessary.


3. Pre application discussions and negotiation with the Council’s Planning Department.


4. Liaise with client the Councils feedback further amendments as required.


5. Preparation of final plans for submission with the planning application.


6. Preparation of a Design and Access Statement or Planning Statement for the application.


7. Planning application submission.


8. On going discussions / contact with the Case Officer during the application.


9. Submission of additional plans / details as required during the course of the application.


10. Submission of discharge of conditions application(s) as required.


11. Preparation and submission of an appeal (if appropriate).

Tom’s Top Tips for Planning

1. Discuss the proposal with your immediate neighbours before the submission of the application.

2. Understand the policy framework surrounding the application site.

3. Design and apply for an extension/ development which is in character with the property or the area.

4. Understand what the extension is to be for and design it for its proposed purpose.

5. Do not disregard neighbour amenity issues.

6. Utilise space as best you can.