Basement extensions and conversions can often be considered permitted development, not requiring an application for planning permission, provided they meet all the necessary planning and design criteria and there are no constraints that restrict or remove your permitted development rights.
Converting an existing residential cellar or basement into a living space can in many cases be done without the need for full planning permission, as long as it is not a separate unit, does not change the use significantly, does not alter the external appearance of the property and there are no constraints.
Excavating to create a new basement or extend an existing basement involves major works, a new separate unit of accommodation and/or alters the external appearance of the house, such as adding a light well, is likely to require planning permission.
For basement extensions and conversions that are likely to fall within permitted development a lawful development certificate is recommended, so that you know your project is compliant and is protected from any retrospective planning issues, enforcements or penalties.
Ultimately, it is the planning officer assessing your application who will make the legal determination and either approve or reject your application. If your application for a lawful development certificate is rejected then an application for full planning permission would be required.
If there are any hidden constraints that limit or remove your permitted development rights, full planning permission may be required even if your project complies with all the permitted development criteria.
Building regulations may also be required depending on the extent of the works. If your basement shares a wall with another other property, you will likely require a party wall agreement.
With any development there are always potential planning constraints which are often hidden that can make the simplest of projects into a very complex planning application.
For every type of development there are certain design criteria that must be met in addition to meeting all of the necessary planning policies, which vary between every local planning authority. For example, an outbuilding is something that could potentially be done under permitted development, however if it doesn’t meet even one of the design or planning criteria then full planning permission would be required.
In addition to this, there are many hidden constraints such as article 4 direction, section 106, conservation areas and even just living under a flight path can remove your permitted development rights meaning everything needs full planning approval. This can literally mean there could be two houses in the same town doing the exact same development and one could be built under permitted development while the other needs full planning permission.
In addition, specialist reports may also need to be submitted with all the usual supporting evidence and drawings. Examples of these include heritage statements, flood risk assessments, transport surveys, wildlife reports and many others.
If the building is listed in addition to securing planning approval you will also require listed building consent and building regulations approval before work can commence. Carrying out any works on a listed building without the necessary approvals is a criminal offence.
If there are any constraints that limit or remove permitted development rights or even one of these criteria is not met, then you are required to submit an application for planning permission.
Even if we believe your project is likely to be considered permitted development, it is always strongly recommended that no work commences until all of the necessary planning and building regulations approvals are secured. Doing so would be at your own risk!
On a daily basis we receive enquiries from clients who have received planning enforcements and been given 28 days to secure planning permission or demolish their development, which is a very costly and stressful situation. 99% of these cases are clients who were sure their development was permitted having either read some info online or been mis-advised by their builder.
In some cases, they could have been permitted with a few minor changes to the design. Sometimes they were permitted at the time of the build but the planning authority have subsequently imposed planning constraints removing their permitted development rights, meaning they now need retrospective planning permission and sometimes it was never going to be permitted development due to the local planning policy.
If you do get it wrong, receive an enforcement and planning permission can’t be approved retrospectively you would need to put the property back to its original state!
To find out what would be required for your basement conversion or extension you have a couple of options. You could submit a formal pre-application to your planning authority with the designs and project brief which you planning authority will respond to indicating what “might be required”. Ultimately the final design and application will determine their decision so the pre-app still does not give you a definitive answer. The process takes 8 weeks and can cost hundreds of pounds excluding any architectural designs.
Alternatively, Studio Charrette who are a partner of the government’s planning portal can conduct a planning appraisal. This involves a chartered planning consultant researching the project to check the relevant planning and design policies, they also check the planning history and look for any hidden constraints. This takes about an hour at which point they can call to advise what would be required and answer any questions. Subsequently we forward the advice in writing.
There are never any guarantees with planning permission or permitted development, because ultimately only your planning authority can make the legal determination. However, with a planning appraisal we can at least let you know whether your proposed development would be feasible, assuming it is what the best route forward would be and the likelihood of success. As part of the planning appraisal, we can also advise you on building regulations, structural engineering calculations and construction.
Assuming the planning appraisal is positive we can then provide a quote for any services you want help with including architectural design, planning permission, building regulations and construction. Should you decide to instruct Studio Charrette can take care of everything for you from start to finish.
Regardless whether you need planning permission, prior approval or a lawful development certificate the process and time frames are very similar. Every type of application requires a variety of supporting evidence to justify why it should be approved, architectural drawings, maps, block plans and of course the correct application to be completed.
Once an application is submitted the planning authority first needs to validate it. They then have up to 8 weeks to process the application and reach a decision. It is however common for planning authorities to request additional information or minor design alterations which can delay the process further.
For this reason, it is recommended that you allow as much time as possible to receive the decision, at least 3 months and up to 12 months ahead is ideal. Once planning is approved you generally have 3 years to start work and 5 years to complete the work.
In theory anyone can submit an application although other than industry professionals those who try are often rejected unnecessarily due to missing information or mistakes. Even architects are generally only qualified in design but not planning so while they can draw anything this does not mean that it meets all of the necessary planning criteria. In fact, lots of clients come to us having been rejected with an architect because the application did not meet the necessary planning criteria.
At Studio Charrette, we have a team of inhouse architects and planners who work together on every application. This ensures the design meets both our client’s expectation and also the expectations of the planning authority, to give every application the best chance of success.
We fully appreciate any unexpected cost is going to be unwelcome, but you will be pleased to know our prices are so competitive, we offer a price match guarantee and in most cases the planning costs are insignificant compared to the development.
If there is a way to help you achieve a positive outcome our chartered planning consultants will give you the best chance of success. Equally if we think it simply isn’t feasible, while it may be bad news, we are obliged to give
If you choose to instruct Studio Charrette, we will take care of everything for you from this point including liaising with the enforcement officer and preparing all the necessary documents to submit to your planning authority.
We will keep you updated from start to finish until we receive a decision, which thanks to our planning appraisals is usually positive.
Don’t leave it until it’s too late!
If you are in any doubt about how to deal with your Basement’s Extension or Conversion Planning Permission,
contact us right away to speak with one of our Expert Chartered Planning Consultants.
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