Plan your extension for free with the Renoserve Living Research Hub
Before committing to a home extension or interior refurbishment, explore the Renoserve Living Research Hub—your free starting point for design ideas, budgeting guidance, timelines, and planning considerations. It helps you understand your options clearly before you begin your project.
We’re the UK’s #1 extension and interior renovation specialists
Based in Blackburn and serving the Northwest, Renoserve Living are specialists in bespoke kitchens, fitted bedrooms, storage solutions, media walls, bathroom suites, and home offices. Our mission is simple: transform your home with design-led solutions that enhance both beauty and function.
Quick summary
This guide breaks down everything you need to know before planning a home extension or major renovation—from types of builds, cost expectations, and ideas to interior design, sustainability, regulations, and working with professionals.
Home extension types
While Renoserve Living specializes in interior refurbishments and bespoke furniture, many homeowners combine these services with extensions such as:
- Rear extensions for larger kitchens or open-plan living
- Side extensions to utilise unused alley space
- Wraparound extensions for maximum ground-floor expansion
- Loft conversions for an extra bedroom or office
- Garage conversions for additional living space
- Garden annexes as studios, gyms, or guest rooms
An extension paired with Renoserve’s interior expertise can completely transform how your home functions.
A note on build costs
Remember that core build prices rarely include VAT, kitchens, appliances, rewiring, decoration, bespoke furniture, windows, or bathroom fittings—all services Renoserve Living can help complete in the finishing stage.
Construction costs have risen over the years, so older quotes from neighbors may not reflect today’s rates.
How much money can DIY save you on a home extension?
DIY can help reduce costs in finishing tasks such as painting or décor, but major work—plumbing, electrics, roofing, demolition, structural changes—should always be completed by qualified professionals to avoid expensive mistakes.
7 tips to keep house extension costs down
- Get an accurate measured survey
- Compare contractor quotes carefully
- Vet your suppliers
- Consider hiring a project manager
- Research materials early
- Move out if necessary to reduce delays
- Choose the right finance option
Financing a house extension
House extension loan
Suitable for small- to medium-scale projects. Quick to arrange but often higher interest.
House extension remortgage
Perfect for larger budgets; you can borrow against your home’s equity at better rates.
Personal savings
Interest-free and straightforward, but less flexible—always keep a contingency fund.
House extension ideas
A side home extension in Lambeth

Using an unused alleyway, this project expanded the kitchen into a stunning broken-plan living area with a glass roof and exposed brick.
A wraparound house extension in Southwark
A small section from the side and rear garden created a spacious kitchen-diner, complete with Crittall doors and matching brickwork for a seamless finish.
Interior design mistakes to avoid in your extension
Many homeowners leave interior decisions for later—but this often leads to costly compromises. Avoid:
- Not planning furniture placement early
- Poor lighting and socket layout
- Mismatched design between old and new spaces
- Losing natural light due to poor window planning
Renoserve Living provides professional design consultation to ensure your space works beautifully from day one.
Environmentally friendly house extensions
How to build an energy-efficient house extension
Focus on:
- Lighting: LED and daylight optimisation
- Heating: efficient systems and smart controls
- Insulation: walls, floors, ceilings, plus high-performance glazing
An eco-focused extension reduces energy bills and improves home comfort.
What is the house extension process?
A typical project includes:
- Measured survey
- Design proposal
- Planning permission/permitted development check
- Structural engineering
- Party wall notices
- Specialist surveys
- Building regulations
- Tendering & contractor selection
- Interior design & installation (where Renoserve Living excels)
Do you need an architect for a house extension?
Not legally—but architects can greatly improve design, add value, and increase planning approval success.
House extension drawings
Most projects require:
- Existing drawings
- New floor plans
- Elevations
- Structural drawings
- Electrical layouts
- Plumbing & drainage plans
House extension regulations
What kind of survey do I need for my house extension?
Measured surveys or laser surveys are ideal for accurate design and planning. Topographic surveys may be required for complex builds.
House extension without planning permission
Many extensions can be built under permitted development rights, though large rear extensions may need prior approval. Always apply for a Lawful Development Certificate.
Can I add an extension to a listed building?
Yes—but you’ll need:
- Planning permission
- Listed building consent
- Designs that respect historic features
Securing party wall agreement for house extensions
If your work impacts a shared boundary or structure, you must follow the Party Wall Act. Serving notices early avoids disputes and delays.
Contents
- Extension types
- Costs
- Financing
- Ideas
- Interior design
- Eco-friendly options
- Process
- Regulations
- Party wall requirements
How much does an architect charge?
Architect fees vary based on service level and project complexity. Many work on a percentage basis, others on fixed packages. Always request a clear, detailed quote.
Research Hub
Explore Renoserve Living’s Research Hub for inspiration, design guidance, cost tools, and detailed advice to help you plan your dream renovation or extension with confidence.