Thinking of extending your home in Essex but unsure where to start with planning permission? You’re not alone.
At Connor Ferris Architects, we help homeowners across Chelmsford, Brentwood, Billericay and beyond turn their ideas into beautifully designed, fully compliant extensions. This guide walks you through the planning process in plain English, with local insights to help you avoid delays and get it right the first time.
Do You Need Planning Permission?
Not always! Some extensions fall under Permitted Development (PD) rights, which means you don’t need full planning approval, but there are strict limits.
✅ You may not need permission if:
- Your extension is single-storey, under 3m deep (4m for detached homes)
- It doesn’t exceed 50% of your garden space
- It’s not higher than the existing house
- You use matching materials
- You’re not in a conservation area or on designated land
Tip: Even if PD applies, we always recommend applying for a Lawful Development Certificate — it protects you legally and simplifies future sales.
When You Do Need Planning Permission
Planning permission is required when your proposal exceeds PD limits or involves:
- Double-storey extensions
- Building near a boundary or public highway
- Alterations in conservation areas, listed buildings, or green belt land
- Changing the use of a building (e.g. garage conversion into a separate dwelling)
The Planning Application Process in Essex
1. Initial Design + Site Assessment
We start by understanding your vision, assessing your property, and identifying potential constraints (like overlooking neighbours or local height limits).
2. Pre-Application Advice (Optional but Smart)
Most Essex councils (like Chelmsford City Council) offer pre-app services. We handle this for you to get early feedback from planning officers and flag any concerns.
3. Preparing and Submitting Your Application
We prepare:
- Scaled architectural drawings
- Location & block plans
- Design & Access statements
- Heritage or sustainability statements (if required)
Your local authority will charge a planning fee.
4. Consultation & Decision (8 weeks)
Neighbours are notified, and the council assesses your application. If needed, we revise drawings during this stage.
✅ Did You Know? We have a 100% success rate on full planning approvals in Chelmsford in 2024.
Local Planning Authority Links
Here’s where to check guidance or submit applications online:
💡 Planning Tips from the Experts
✔️ Always consider how the extension fits with your existing architecture
✔️ Involve neighbours early — objections can delay decisions
✔️ Invest in quality drawings — rushed applications often get rejected
✔️ Get a Lawful Development Certificate, even if PD applies
✔️ Speak to us before hiring a builder — your design may not be compliant yet
Case Study: Sustainable Home Extension in West Mersea, Essex
We have recently secured full planning approval for a transformative extension and sustainable redesign in West Mersea, a coastal town in Essex known for its conservation sensitivity and strict planning constraints.
Our client wanted to modernise and extend their traditional home while improving thermal performance, natural daylight, and layout flow, without compromising the character of the area.
Key features:
- Full-width rear extension with a low-energy design
- Integration of natural timber cladding and energy-efficient glazing
- Reconfiguration of internal layout to optimise passive solar gain
- Carefully designed roof profile to minimise impact on neighbours
With a sensitive site and ambitious brief, we collaborated closely with the client and planning officers to ensure a smooth, successful outcome, blending aesthetics, function, and sustainability.
📞 Need Help Getting Planning Permission?
Whether you’re in Chelmsford, Billericay, or anywhere across Essex, we’ll help you:
- Understand if you need permission
- Produce high-quality drawings
- Manage the full application process
- Increase your home’s value and liveability
👉 Book your free planning consultation here or call us.
