rear extension
Enhance your living space and garden connection.
A rear extension adds space at the back of your house for a larger kitchen, dining room or living area. BCS designs and builds house extensions in London, with the layout developed around how you want to use the new room and connect it to the existing house and garden.
Start with the decisions that shape the design: where the kitchen will sit, how you will move between rooms, and where doors and rooflights can bring in daylight. Our Greenwich house extension gallery shows a completed project with a kitchen, dining space and glazed doors to the patio.
For an early budget discussion, read our London extension cost guide. If you are considering underfloor heating, compare wet and electric systems before the floor build-up is agreed. The right specification depends on your home and the proposed work.
side return extension
Utilise unused space for a bigger, brighter home.
A side return extension uses space beside the house to widen the ground floor. It can make room for a larger kitchen, a dining area or a utility space without relying on a long rear addition. The useful gain depends on the existing layout and the space available.
Think about the route through the house as well as the new floor area. Where will daylight reach the middle room? How will the kitchen connect to the garden? Our side return and wraparound comparison helps you work through those choices for a London terrace.
BCS works with homeowners from design through to construction. Planning permission and permitted development are different routes, not interchangeable promises. Read our extension planning guide, then confirm what applies to your property before the scope is agreed.
wraparound extension
Create a spacious, open-plan ground floor.
A wraparound extension combines a side addition with a rear extension. It offers scope to rethink the ground-floor layout rather than simply adding one room, bringing kitchen, dining and living space together where the property allows.
Compare the extra space with the work needed to connect it to the existing house. Discuss the position of the kitchen, structural openings, daylight, garden access and heating before choosing the layout. A wraparound scheme is not automatically the best option for every terrace; a smaller side return or rear extension may answer the brief.
Our extension layout guide sets out the differences. The London extension timeline explains the stages to discuss with your builder. To talk through a scheme with BCS, send us your project details.
double storey extension
Double the space and increase home comfort.
A double storey extension is the perfect solution for homeowners looking to significantly increase their living space, both on the ground floor and upstairs. Whether you need more space for a larger kitchen, additional living areas, or new bedrooms, a double storey extension offers a versatile way to expand your home.
Our team will work with you to design a seamless extension that blends perfectly with the style of your home, ensuring it looks as though it has always been part of the property. With our commitment to high-end finishes and exceptional craftsmanship, we guarantee a luxurious, functional space that enhances your lifestyle.
From obtaining planning permissions to managing every aspect of the build, we ensure the entire process is stress-free and runs smoothly. A double storey extension not only meets your immediate needs for more space but also adds significant value to your home, making it a smart investment.
loft extension
Add value with extra rooms and natural light.
A loft extension is a fantastic way to unlock the potential of your attic space, creating a functional and luxurious new room without altering the footprint of your home. Whether you’re looking to add an extra bedroom, home office, or a private retreat, a loft conversion can transform your home in ways you never imagined. Our experienced team works closely with you to design a space that meets your needs while blending seamlessly with the rest of your home.
From obtaining planning permissions to managing the construction, we handle every detail with precision and care. With high-end finishes and luxurious touches, we ensure your new loft space is not only practical but also adds a touch of elegance to your home. Throughout the project, we maintain clear communication, ensuring your vision is brought to life with minimal disruption. A loft extension is a great way to add both space and value to your property.
flat roof extension
Modernise your home with a clean, minimalist look.
A flat roof extension offers a sleek, modern aesthetic that’s perfect for contemporary homes. Ideal for kitchen or living room extensions, a flat roof provides a clean, minimalist look while allowing for large windows and skylights to flood your home with natural light. Our team specialises in designing and building flat roof extensions that are not only visually striking but also highly functional. We use high-quality materials and luxurious finishes to ensure your new space feels both modern and welcoming.
From initial design to the final touches, we handle every aspect of the project, keeping you informed at each stage to ensure a smooth and stress-free experience. Whether you’re looking to create a larger kitchen, an extended living space, or a more open-plan layout, a flat roof extension can add both style and value to your home. Let us help you create a contemporary space that enhances your living experience.
pitched roof extension
Achieve timeless style with increased natural light.
A pitched roof extension offers a timeless, classic look that complements both modern and traditional homes. By adding height and architectural interest, a pitched roof extension can create an airy, spacious feel that enhances the overall aesthetic of your home. Our team of skilled craftsmen will design and build your extension with the highest attention to detail, ensuring the new space blends seamlessly with your existing property.
Whether you’re looking to add a new room or expand an existing one, a pitched roof extension offers the perfect balance of style and functionality. We use only the best materials and finishes, ensuring that the final result is both luxurious and durable. Throughout the project, we prioritise clear communication and a smooth process, taking care of everything from planning permissions to construction. A pitched roof extension not only adds beautiful living space but also increases the value of your home.
Planning an extension? Start with the practical questions
Before comparing quotes, check the likely budget drivers, the project sequence and which layout suits the house. These guides cover the questions London homeowners ask first.
Extension costs in LondonSee what moves the budget before asking for a quote. Side return vs wraparoundCompare layouts for a London terrace. Extension timelinePlan survey, approvals, structure, build and handover. Choosing a builderReferences, insurance, quotes and contract checks. Underfloor heatingCompare wet and electric systems before the floor build-up is fixed.
See a completed house extension in Greenwich, browse more BCS projects, or request a free quote.
Completed projects across London
These are finished BCS projects with published photographs. Each gallery shows the completed work rather than a visualisation.
North and east London
Oldfield Rd, N16 — rear extension, Albion Road, N16, Albion Drive, E8, Strone Rd, E12, Brooksbys Walk and Globe Road.
South and south-east London
Greenwich house extension, Sanderstead Avenue, Bayston Road and Avondale Rise.
Wider London and Surrey
Arica Road, Stag Leys, Surrey KT21 and a London pub renovation. See every gallery on the projects page.
Before you appoint anyone
Ask every builder for the same information: two or three recent references you can actually contact, written quotes rather than estimates, proof of the insurance that applies to your project, and a written contract with an agreed payment schedule. Citizens Advice and TrustMark both set out the same sequence. Our guide to choosing a house extension builder in London explains what to ask for at each step — apply it to BCS as well as to anyone else quoting.
Our Seamless extension process
1
consultation
We begin with a thorough consultation to understand your vision, preferences, and practical needs. Our team takes the time to explore all possibilities with you, offering professional advice and insight into the best house extension options for your space and budget.
By establishing clear goals from the start, we ensure the project is aligned with your expectations before moving forward.
2
design
Our experienced designers develop bespoke plans tailored to your exact specifications. We focus on creating functional, stylish home extension layouts that complement your home. We collaborate with you throughout the design phase, refining details until you're completely satisfied.
Our goal is to combine beauty and practicality in every project, ensuring the final design is both aesthetically pleasing and highly functional.
3
planning permissions
We prepare and coordinate the information a planning or permitted-development route needs, and we keep the process moving where it is within our control. Whether your project needs householder planning permission, falls within permitted development, or is worth confirming with a lawful development certificate depends on the property, so we check that position first.
The decision itself belongs to the local planning authority. We will tell you what we can influence and what we cannot.
4
build
Our highly skilled team of builders ensures your project is executed to the highest standards. We use quality materials and meticulous craftsmanship to bring the design to life. Throughout the build, we maintain open communication, keeping you informed on progress while minimising disruption.
We agree a project-specific programme once the scope and site conditions are clear, and we tell you promptly when something changes it.
5
completion
Upon completion, we carry out a comprehensive inspection to ensure every detail meets our rigorous standards and your expectations. We’ll walk you through the finished extension, addressing any final touches or questions.
Our commitment to high-end finishes means your new extended space will not only meet functional needs but will also feel like a luxurious addition to your home.
4
build
Our highly skilled team of builders ensures your project is executed to the highest standards. We use quality materials and meticulous craftsmanship to bring the design to life. Throughout the build, we maintain open communication, keeping you informed on progress while minimising disruption.
We agree a project-specific programme once the scope and site conditions are clear, and we tell you promptly when something changes it.
5
completion
Upon completion, we carry out a comprehensive inspection to ensure every detail meets our rigorous standards and your expectations. We’ll walk you through the finished extension, addressing any final touches or questions.
Our commitment to high-end finishes means your new extended space will not only meet functional needs but will also feel like a luxurious addition to your home.
common extension concerns answered
- Do I need planning permission for my extension?
- How long will the extension process take from start to finish?
- What are the potential costs and can I get a detailed quote upfront?
- How will the construction impact my day-to-day life?
- Are there any restrictions for extensions in conservation areas or listed buildings?
- What insurance or guarantees are in place for the work?
- Can you handle building regulations and inspections?
We’d love to hear from you
browse our completed projects
Rear Extension
House Extension
House Extension
House Extension
Daniel and his team at BCS are first class. Quality of finish is excellent and they creatively find solutions to building challenges. Daniel takes great pride in his work and will only offer robust solutions that are fit for purpose. We refurbished our whole house with an extension they finished on time and with very little snagging. I would thoroughly recommend.
Michael, London
Job completed on schedule and on budget. What more can you ask? We have been back in our house for two months after a major renovation and are completely delighted with the general workmanship and quality. There have inevitably been other contractors on site (kitchen fitter and renewable energy supplier) and Daniel and his team have collaborated seamlessly with them. There have been a few trivial issues since we have moved in that have needed to be addressed and these have been dealt with in a prompt and unquestioning manner. We can fully recommend BCS.
Julian, London
Daniel and his team completed a new-build house for us in 2022. We are now enjoying living in the beautiful, stylish home that he created. He was always reliable, efficient and highly professional throughout the build process and beyond. We were impressed by the quality of his work and the conscientiousness of his team, who consistently worked to a high standard. Daniel is an excellent communicator and was always able to resolve issues and find solutions quickly and effectively. We would highly recommend him.
Alexis, London SE15
Daniel and the BCS team did a brilliant job extending and renovating our home. Their work is really high quality, they kept the project on schedule and were very reliable, helpful and responsive throughout the process. We would certainly recommend BCS to others!
Clare, London