Rear House Extensions in Essex
Feeling boxed in at home? A rear house extension unlocks the potential of your property, extending into your garden to create a bright, open space for modern living, without the stress or cost of moving.
Book your free rear house extension consultation today.
Transforms everyday living
Create open, social spaces for cooking, entertaining, and family time.
Increases property value
Professionally built rear extensions can raise your home’s value by up to 25%.
Brings in more light
Roof lanterns, skylights, and bi-fold doors fill your home with natural daylight.
What is a Rear House Extension
A rear extension is one of the most popular home improvement projects in the UK, extending the back of your property to add valuable living space. It’s ideal for open-plan kitchens, dining areas, or lounges that connect seamlessly with your garden.
Whether you own a Victorian terrace in London, a semi-detached in Essex, or a detached home in Hertfordshire, a rear extension lets you reimagine your home layout while maximising light, flow, and functionality.
Why Choose KNR Group for Rear House Extensions
KNR Group has over three decades of experience designing and building rear extensions across London, Essex, and Hertfordshire. Our team manages everything from planning to construction, ensuring every project runs smoothly and finishes on time.
- In-house architectural design and planning support
- Transparent pricing and realistic timelines
- Skilled local tradespeople and project managers
- Commitment to sustainability and quality materials
Contact KNR Group today for your free on-site survey and quotation.
Types of House Extensions
Our Process
Consultation and Site Survey
We assess your property, discuss your goals, and outline potential layouts.
Architectural Design
Tailored designs that meet your space, budget, and style preferences.
Planning and Building Control
KNR Group manages all permissions, drawings and compliance paperwork.
Construction
Managed by qualified professionals, ensuring precision, safety, and efficiency.
Completion
Every project is signed off with final inspections, certification, and warranties, ready for occupancy or sale.
Project Timelines
On average, a rear extension takes 10–16 weeks to complete, depending on size, weather, and specification.
KNR Group provides clear timelines from the start, keeping you informed at every stage of the build.
Cost of a Rear Extension
The cost of a rear extension depends on the size, design, and level of finish. Typical guide prices:
| Type | Average Cost |
| Single rear extension | £40,000 – £70,000 |
| Double storey rear extension | £80,000 – £130,000 |
| Wraparound (L-shaped) | £90,000 – £150,000 |
We provide detailed, itemised quotes with no hidden extras — so you know exactly where your investment goes.
Planning Permission for Rear Extensions
Most rear extensions in Essex and London fall under permitted development rights, provided they meet size and height limits:
- Up to 3 m deep for terraced homes, 4 m for detached properties
- Must not cover more than half of the garden area
- Matching materials and rooflines are required in some areas
KNR Group’s planning team will confirm whether you need permission and manage the entire application process on your behalf.
FAQs – Rear House Extensions
How much does a rear extension cost in Essex?
A typical rear extension in Essex costs between £40,000 and £70,000, depending on design, size, and materials. KNR Group provides detailed, transparent quotations for every project.
Do I need planning permission for a rear extension in London?
Many rear extensions in London can be built under permitted development rights, but you’ll need planning permission if your home is listed, in a conservation area, or the extension exceeds the size limits.
How long does a rear house extension take to build?
Most builds take 10–16 weeks, including foundations, structure, and finishes. More complex or double-storey projects may take longer.
What’s the difference between a rear and wraparound extension?
A rear extension extends directly from the back of your property, while a wraparound combines side and rear extensions in an L-shape to create even more internal space.
Can a rear extension add value to my home?
Yes — a well-designed rear extension can add 15–25% to your property’s market value, making it one of the best home improvement investments.
Why KNR Group is Trusted for Rear Extensions
- Expert Design & Build – Complete service from concept to completion.
- Local Knowledge – We understand Essex and London planning requirements.
- Customer-Focused – Dedicated project managers and consistent communication throughout.
Book your free design consultation and see how KNR Group can transform your home.
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House Extensions & Renovation Projects
Client testimonials
Video Testimonial
This rear extension showcases KNR Group’s ability to deliver a smooth, well-managed build from start to finish. With clear communication and quality craftsmanship throughout, the result is a bright, open space that’s transformed how the homeowner lives day to day.