Planning consent usually falls into two types – Outline Consent (OPP) and Detailed Consent (DPP).

OPP is where the permission to build a dwelling has been agreed in principle but where a number of design details have yet to be finalised. DPP is where the application contains sufficient design details for a full approval to be granted (usually with a few conditions) which will last for three years.

The journey from an Outline Consent to Detailed Planning permission will be straight forward for the majority but a potential horror story for others. Best described as the ‘elastic part’ of your programme, seeking detailed planning approval can be a highly charged affair involving delicate negotiations between yourselves, as future occupants, your neighbours, the local authority planning officials and, in many instances, the full planning committee.

Technically a properly submitted application should take no more than six to eight weeks before being determined and, for the best chance of achieving the right result, there are plenty of ways to help mitigate failure. They’re not without physical cost but, in addition, you should also allocate sufficient time to be able to make a positive contribution to the process.

Implications included in the outline consent

An approved outline consent will already include a location plan showing the full extent of the plot boundaries and relationship with other neighbouring properties, a design and access statement (DAS) giving the background rationale for why how the new building will evolve and, quite often a street scene indicating its proposed new shape and mass. The outline permission will last for a period of three years during which time you will be required to submit what is called a reserved matters application.

These ‘reserved matters’ will include the full architectural design of your new building with scaled floor plans and elevations providing details concerning the proposed external materials, glazing, access and landscaping.  It will be necessary to pick up and refer to any conditions that were listed in the outline consent which may include such matters and building lines, building heights, boundary glazing etc., and, of course, these will need to be consistent with any references made in the DAS.

Replacement dwellings

Replacement dwellings generally follow a different route as there is little to be gained from submitting an application for outline consent as, and firmly on the basis that the building you intend to replace is still ‘habitable’, you already have residential rights over the land in question.

In these circumstances the usual process would be to submit a full (detailed) planning application for which there will be different levels of guidance provided by your planning authority.  We see many examples of single buildings making way for new multiple units in all different typologies (apartments, terraced, semi detached etc.,) and there are also copious examples of small single buildings being replaced by much larger ones.

Generally, the presumption to increase density will be looked at more favourably within town and village development boundaries whereas replacing a single house in the countryside will be much more regulated in terms of any increase in size.  Some Councils offer a scale of increase, say + 20%, as guidance and others refer only to the design of the replacement dwelling being in character with the original.

Planning, as you will have realised, is far from an exact science and the subjective nature of its assessment, the opinions of all those involved and the interpretation of planning guidance is what fuels our emotional responses.

Planning Costs

From a financial perspective the planning portal lists all of the fees payable (and there are many different categories of application) with outline amounting to £335 for each 0.1 hectare and reserved matters or full applications costing £335 per individual dwelling.  In addition to this will be your designer’s fees which are all individually negotiable based upon their experience, size of practice, complexity of your design, value of the project, etc.  My experience suggests that your designer’s fees could start from as little as £2,000 but this scale could go up to 4% of the indicative project costs.  In addition, most designers work on a time-charged basis and so if your design development phase is protracted (for whatever reasons) you will need to budget for higher fees.

Taking a standard design from a book of plans, while tempting, is not recommended as it is unlikely that a standard conceptual house-type will automatically suit your plot without some form of refinement. Standard designs are, however a great idea to help you identify your preferences and get the design brief prepared.

Preparation of your design brief

The more thorough you can be in defining your wish list, then the more likely it is that you will end up getting what you want.  My advice has always been to create a file of all the design features you like in properties you have seen, e.g. roof shapes, chimneys, dormers, glazing styles etc., so that these can be discussed with your designer right at the outset in terms of their suitability and their cost. These details, together with your accommodation requirements and room size particulars will give your designer all the information they need to create your fully inclusive ideal solution.  Their job will be to balance this wish list with your defined budget, the individual plot characteristics and, finally, by using their experience to determine what is likely to be deemed acceptable.

Appointment of your designer

Finding a designer capable of doing the above is an exercise on its own. If you have friends or family who have some successful project experience then they may well be able to make an introduction for you.  Failing that you could visit your local planning office, inspect the latest submissions and, for those where you like the quality of the work, collect the designer’s details.

Regardless of how you identify potential designers, you’ll want to satisfy yourself on four different levels before appointment:

  • First, have I seen and do I like the quality of their work, both design content and presentation
  • Second, is there a good chemistry match? I think this is crucial in all subsequent working relationships
  • Third, am I clear about, and comfortable with, their proposed fees?
  • Fourth, how available are they and can they manage my timetable?

Survey information

With the more contentious applications, it may be necessary to gather additional survey information to help articulate, reinforce or justify your proposals. With sloping sites a full topographical survey may be necessary to identify all relevant levels which is likely to cost between £350 and £800 depending on what is involved.

Street scene photography with graphical insertions is quite common place and this really helps all stakeholders to get a feel for the final outcome.  Some people prefer physical modelling which is becoming much more affordable with the advent of 3-D printing.

Traffic surveys are a favourite in urban spots which add expense in both the physical survey cost and also in terms of time.  However, this is likely to have been dealt with as part of an outline application to justify the principle of consent, and shouldn’t be necessary for a replacement dwelling.

Discussion with the wider stakeholders

Seeking early feedback from the planning team is sensible as it will help you and your designer to understand their perspective.  Planning officers should consider your proposals purely on fundamental planning issues which are based on environmental impact, character and local suitability and not necessarily architectural expression.

In addition, taking time to get your neighbours on side will pay dividends in the long run and, where they have fundamental concerns based on sound planning principles, you should be prepared to negotiate and accommodate their comments if at all possible.

Attending panning committee meetings

And finally, if your application has been included in a full committee hearing it’s probable that your application has met with some key objections along the way.  Many Councils will now let you attend and make (controlled) representations on the day before a final vote is taken.

Useful Contacts


This article was written by Tim Doherty, and originally published for Build It Magazine. Tim is the Director and Principal Surveyor at Dobanti Chartered Surveyors, a building surveyors based in Tunbridge Wells, Kent. Dobanti offers a wide range of property services to manage/ support design and planning applications, in addition to full project management, and building surveysGet in touch for more information, or read more online now. Further articles and blog posts can be found here.