Build Joy Ltd’s Expertise in House Extensions: Smart Design, Compliant Builds, Seamless Execution - Introduction
As property prices continue to rise in Greater London and across the UK, homeowners are turning to a smarter solution: extending instead of relocating. Whether it’s to expand a kitchen, create a home office, or add entire new bedrooms, house extensions offer a practical way to enhance space, boost property value, and customise your living environment without the costs of moving.
At Build Joy Ltd, we specialise in delivering stunning, regulation-compliant home extensions tailored to your lifestyle and budget. From small infills to wrap-around transformations, we manage the entire process from planning to handover — so you don’t have to.
Types of House Extensions You Can Add to Your Property
Small Infill Extensions
This is the least invasive option, involving the installation of skylights without altering the roof’s structure. It’s typically allowed under Permitted Development (PD) rights and is ideal for homeowners looking for a cost-effective and fast loft upgrade.
3m Rear Extensions (Under Permitted Development)
One of the most popular options among UK homeowners, the 3-metre rear extension (or 4 metres for detached houses) allows you to extend outward from the rear of your home without formal planning permission — as long as the extension remains single-storey and meets material and height conditions.
This is perfect for kitchen diners, open-plan living areas, or playrooms, all delivered faster and with fewer council restrictions.
Side Return Extensions
Side returns make clever use of that narrow alley beside terraced or semi-detached homes. By extending into that space, you can dramatically widen kitchens or dining areas, making room for bi-fold doors, kitchen islands, or more natural light.
Often combined with rear extensions, side returns are one of the most transformative yet space-efficient extension types.
Double Storey Extensions
Need more than ground-floor space? A double-storey rear or side extension adds significant square footage vertically, accommodating extra bedrooms, bathrooms, or workspaces.
While these require full planning permission and careful design for privacy and scale, they unlock real resale value and are ideal for growing families.
Back Single Storey Extensions
A more traditional but flexible option, rear single-storey extensions stretch out your ground floor without altering the structure too heavily. Whether you’re adding a larger lounge, utility room, or an open-plan family zone, this is often a budget-friendly solution with big lifestyle rewards.
Wraparound Extensions
Wraparounds combine rear and side return extensions to form an L-shaped addition. These maximise your ground floor’s potential, offering a wide, open layout that’s perfect for contemporary living.
Due to their scope, wraparounds usually need planning permission, but the resulting space and flow are well worth the investment.
House Extension Process Step-by-Step
1. Planning & Design Stage
It all starts with measuring, vision, and a feasibility review. Our architects work closely with you to understand your goals, design preferences, and how your property can evolve — all while staying within legal and technical limits.
2. Submitting Planning or PD Notifications
Depending on your chosen extension type, we’ll either submit a Permitted Development application or a full Planning Permission request. We also handle:
- Party Wall Agreements
- Drainage & ecology checks
- Lawful Development Certificates (LDCs)
- Design & Access statements for planners
3. Structural Calculations & Building Control
A strong, safe extension needs robust engineering. Our in-house team handles:
- Load-bearing calculations
- Steel beam and joist planning
- Building Control submissions
- On-site inspections at key stages
4. Appointing the Right Construction Team
Choosing the right builders is crucial. At Build Joy Ltd, you benefit from a fully integrated team — no need to juggle architects, builders, and inspectors separately. You get real-time updates, transparent pricing, and a single point of accountability.
5. On-Site Construction Phases
Here’s what you can expect:
- Site clearance, demolition, excavation
- Groundworks and foundation pouring
- Steelwork and structural framing
- Roof installation, glazing, and insulation
- Internal works: electrics, plumbing, plastering, and finishes
Our projects are managed cleanly, safely, and always to code.
6. Final Inspection, Snagging & Sign-Off
After the build, we complete a thorough snagging process, arrange Building Control inspection, and issue a Completion Certificate. We also provide:
- Updated EPC (Energy Performance Certificate)
- Product and build warranties
- Post-handover support
Benefits of Adding a House Extension
- Stay in your neighbourhood and school district
- Customise your home layout for modern living
- Significant increase in resale value
- Improved insulation and energy efficiency
- Avoid legal fees, stamp duty, and moving costs
- 0% VAT relief on some extensions tied to disability adaptations or new build annexes (check with our team for eligibility)
Disadvantages & Cost Considerations
- Requires careful navigation of planning and building regs
- Costs vary: small infills may start at £30,000; double-storeys or wraparounds can exceed £120,000
- May need neighbour approval (e.g., Party Wall Agreement)
- Disruption to home life during construction
- Some extensions may not qualify for 0% VAT
Why Choose Build Joy Ltd for Your House Extension?
Compliance Experts
From Permitted Development to complex wraparound planning, we know the local regulations — and how to navigate them fast and cleanly.
Quality Workmanship
Our engineers, architects, and tradespeople are experienced, vetted, and focused on excellence at every stage — from your first sketch to your final sign-off.
End-to-End Service
We manage the whole journey: designs, permissions, construction, and inspections. We don’t just build extensions — we build trust, comfort, and long-lasting relationships.
Conclusion
Whether it’s adding a side return for a dream kitchen or building a double-storey extension for your growing family, the right house extension can completely transform how you live. It’s about space, value, and lifestyle — and with the right team, it’s an exciting and rewarding experience.
Build Joy Ltd is here to help you extend with confidence. Get in touch today, and let’s turn your vision into reality — beautifully, safely, and smartly.
