What Councils Look For in a Home Extension Planning Application
At Plan It UK, one of the most common questions we hear from homeowners seeking planning permission for a home extension is:
“But my friend down the road got theirs approved, so surely mine will be fine too?”
Or sometimes:
“My friend told me this would be Permitted Development.”
We completely understand — the planning permission process can feel confusing and even inconsistent at times.
But the truth is, every planning application for a home extension is assessed individually, based on its own specific circumstances. What was approved for one property doesn’t automatically mean your extension will be approved — even if it’s just a few doors away.
Here’s a simple guide to what councils actually look at when reviewing your home extension plans — and how at Plan It UK, we give your project the best possible chance of success.
1. Local Character of the Street
When assessing your home extension planning application, planning officers ask:
“Does this extension fit the character and appearance of the local area?”
Even if a neighbour has built something bold or unusual, the council may now be working to preserve a more consistent style across the street.
At Plan It UK, we’ll carefully assess your street’s existing character and design your extension to complement it — without sacrificing your personal vision. We balance your dream design with what’s most likely to gain planning permission.
2. Latest Planning Policies
Planning rules and policies aren’t set in stone — they evolve over time.
What may have been approved two or three years ago might not meet today’s stricter design standards or environmental regulations.
We always check the latest:
Local Planning Policies
Supplementary Planning Documents (SPDs) — detailed local guidance for home extensions
National Planning Guidelines (where applicable)
Our team stays fully updated on planning policies across Bexley, Bromley, Dartford, Lewisham, Greenwich and the surrounding areas of Kent, London and Essex, giving your application the best chance of approval.
3. Permitted Development Rights (If They Apply)
Not every property benefits from Permitted Development rights — which allow certain extensions without the need for full planning permission.
You’re unlikely to have Permitted Development rights if:
Your home is in a Conservation Area or National Park
It’s a Listed Building
You’re part of a new development with restrictions
Permitted Development rights have been removed (known as an Article 4 Direction)
Your property is a flat or maisonette
At Plan It UK, we don’t just guess — we thoroughly check your property’s status.
Our initial review confirms whether Permitted Development is an available route, saving you time and avoiding unnecessary applications.
4. Previous Planning Approvals (and Their Conditions)
The best way of predicting the council’s response is to find a strong precedent for what you’re wanting to do.
A precedent is an example of something that has been done before, which can be used to guide or support decisions in the future. In architecture and planning, it often means looking at a previous project that was approved to show what is possible or acceptable in a certain area.
To establish a precedent, we check out your local council’s planning portal and search for recent approvals to support your project. We ask the following questions:
How similar are the projects? (e.g. size and type of extension/conversion)
How similar are the houses? (e.g. are they both detached properties?)
How similar is the neighbouring context? (e.g. proximity of the extension to neighbouring properties and garden spaces)
When was the scheme approved? (We ideally want a recent approval under the same policies, see earlier section for more information)
Has the project been built exactly as approved? (If it’s been built differently, it might not be legal and therefore isn’t a precedent)
Are there any conditions or constraints to be aware of?
While it’s important to recognise that planning permission is never guaranteed; we can give you the best chance of approval by finding examples that tick all of the boxes above to support your application. If it’s possible to obtain planning permission, we’re confident that we’re the best team to make it happen.
If we believe your project carries a risk of refusal, we’ll always tell you so that you can choose to mitigate the risks with a more acceptable design; or take additional steps to build rapport with the council by seeking their advice before submitting the application.
5. Specific Local Restrictions
If your home falls into any of these categories, extra planning restrictions will apply:
Conservation Areas — emphasis on preserving historic and architectural character
Listed Buildings — historically significant buildings with stricter rules for design and materials, even internally
Green Belt Land — significant limitations on size and scale of extensions
National Landscape (previously known as Area of Outstanding Natural Beauty) — development must conserve and enhance the natural beauty of the area, with stricter scrutiny on visual impact and design quality
National Parks — highly protected landscapes where development is tightly controlled to prioritise conservation, public enjoyment, and natural beauty
Plan It UK has extensive experience navigating sensitive planning applications, ensuring your project meets all necessary requirements.
Final Thoughts: Every Home is Unique — and So Is Every Planning Application
It’s natural to compare your project to what friends, family, or neighbours have achieved.
However, every planning decision is based on:
The specific features of the site
The most up-to-date planning rules
How well the proposal fits into the local environment
At Plan It UK, we take the time to properly research, understand, and plan your project, giving you the best possible chance of a smooth, successful planning permission approval.
Thinking about extending your home?
Get in touch with Plan It UK today — we’ll help you plan smart, design beautifully, and navigate the planning process with confidence.
Book a free consultation or call us today to find out how we can take your vision from concept to construction — all under one roof.
