Home Extensions London
Turnkey Design & Build

We create beautiful, modern home extensions that expand your living space and enhance your quality of life. — Click Here
Bespoke Home Extensions in London

Creating Your Perfect Living Space

In the heart of London, where space is the ultimate luxury, a home extension is more than just an investment in property; it’s an investment in your lifestyle. Our mission is to create exceptional spaces that not only look stunning but feel intrinsically right. We specialise in crafting Modern House Extensions that are a true reflection of our clients’ personality, tastes, and the way they want to live.

Our award-winning team of architects, designers, and project managers approaches every project with passion. What’s more, we utilise cutting-edge BIM (Building Information Modelling) technology in our Design & Build process. As a result, we eliminate guesswork and provide absolute certainty. You can virtually walk through your new space long before the first spade hits the ground. Furthermore, we provide complete transparency on costs and timelines, giving you peace of mind and total control at every stage.

Whether you’re dreaming of a light-filled Kitchen Extension London to become the new heart of your home, or need an extra floor for your growing family, we are here to turn your vision into a beautifully crafted reality.

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The Design & Build Process

Full Control & A Fixed-Price Guarantee

The traditional building process can be fraught with frustration, as it often leads to conflicting visions, hidden costs, and delays. That’s precisely why we created our end-to-end Design & Build service. It’s a fully integrated approach that revolutionises how home extensions are delivered in London. This means one cohesive service, one point of contact, and one team dedicated entirely to your project. Here are the key benefits of our approach.

Complete Clarity From Day One
  • Before any work begins, we create an intelligent 3D model of your home. Thanks to BIM and virtual reality, you can see and ‘feel’ the final result. Consequently, you can make informed decisions with confidence, which eliminates the risk of costly mistakes during construction.
Total Budgetary Control
  • Our 5D BIM system dynamically links the 3D model to a detailed cost plan, so any design change instantly updates the budget. You receive a fixed-price contract from us. This means no surprises and complete financial predictability.
Saving Time & Reducing Stress
  • We coordinate every aspect of the project, from securing planning permission to the final finishes. A single, unified team means seamless communication and a significantly shorter project timeline. Our expert Double Storey Extension Builders manage every detail, thereby minimising disruption to your daily life.
A Guarantee of Uncompromising Quality
  • Because the design and construction are in one pair of hands, we take full responsibility for the finished product. Our integrated team ensures that the architectural vision is executed with the utmost precision. Our process is more than just building; above all, it's about creating a partnership based on trust.

Types of Home Extensions

Choosing the right type of extension is fundamental to a successful project. Our team will help you understand which option will make the best use of your available space. Below are the most popular types of extensions we deliver.

Rear House Extension

One of the most popular ways to add living space is by extending out into the garden. This is the perfect solution for creating a large, open-plan kitchen and dining area. Features like stunning bi-fold or sliding doors can seamlessly blur the line between inside and out, creating flow. A Single Storey Extension London of this kind has the potential to completely transform your entire ground floor living experience.

Side Return Extension

Many London homes, particularly Victorian terraces, have a narrow, underused alleyway. The Side Return Extension cleverly incorporates this space to transform your layout. It allows you to widen your kitchen or living area and bring in huge amounts of natural light through new skylights or glazing. This popular solution adds valuable square footage without sacrificing a significant portion of your garden.

Wrap Around Extension

An ambitious combination of side and rear extensions, the Wrap Around Extension forms a distinctive ‘L’ shape around your property. It delivers the most substantial increase in floor space, allowing for a total ground-floor transformation. This design is the ultimate solution for creating spectacular, multi-functional living zones, perfectly suited for a large kitchen-diner and an enhanced connection to the garden.

Double-Storey Extension

If you need extra bedrooms, a playroom, or a home office upstairs, this is the ideal solution. A two-storey extension is more cost-effective per square metre than building two separate single-storey extensions, as it uses the same foundations and roof. Our highly experienced Double Storey Extension Builders are true specialists in managing the unique complexities of these impressive high-impact projects.

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See your home in 3D before we build

Before any design or construction work begins, we start with a detailed digital survey of your property. Using advanced scanning tools, we capture accurate measurements and convert them into a precise 3D model – known as Scan to BIM.

This process allows you to:

Explore Our Virtual Tours

Our 3D scanning technology doesn’t just support design and construction – it also creates stunning virtual tours. Whether you’re planning, promoting or presenting a space, we deliver high-resolution digital walkthroughs straight from the same scan used for your BIM model.

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Your Benefits

An End-to-End Service

Deciding to extend your home is exciting, but it can also be daunting. Therefore, our goal is to completely shield you from the complexities of the process. We offer a truly comprehensive service, which means we manage every single detail of your project.

A Single Point of Contact

You are assigned a dedicated Project Manager from start to finish. This is your trusted contact who knows every detail, will answer all your questions, and provide regular progress updates. Thanks to this, you avoid the frustration of chasing multiple companies.

Full Planning & Permissions Management

Navigating London’s planning regulations can be complex. Our team takes this entire burden from you. We prepare and submit applications for Planning Permission and ensure full compliance with Building Regulations.

Visualisation and Design Confidence

With BIM technology, you don’t have to rely on your imagination. You can see your new space and test different layouts and materials. Consequently, you can be certain that the final result is exactly what you want.

Financial Transparency & A Fixed Price

Our BIM-led process ensures a highly accurate quotation. Once the design is approved, you receive a fixed-price contract. This means all costs are known upfront.

" Working with Reltic BIM was an absolute pleasure from start to finish. Their professionalism, clear communication, and forward-thinking use of BIM technology truly set them apart from other firms we've worked with in the past. "
Jake Williamson
" We recently used Reltic for loft conversion and they were extremely throughout and we would recommend them highly to anyone else looking for an honest, reliable and hard working team to transform their loft. "
David Klane
" I have taken Reltic's services twice in recent times. They have very professional service, provide a detailed report and excellent customer service. All my queries and calls were answered quickly. Highly recommended. "
James Patterson
" Working with Adrian is always a pleasure, and I won't ever use another estimator. Each task was completed quickly and precisely. always outperforms bids and prices from competitors. Highly recommended! "
Rob Durham
" Professional individuals. They give exactly what they promise because they are skilled at what they do. You can trust these individuals with all of your work, as they are incredibly dependable and polite, in my opinion. "
Sara Brown
House Extension FAQ

Your Questions Answered

 Find clear answers to common questions about costs, planning permission, and the Design & Build process for your London home extension.

Every project is unique. However, a typical timeline for a standard ground-floor extension is as follows: the design and permissions phase takes 3-5 months, and the construction itself takes 4-6 months. The entire process, from our first conversation to completion, usually takes between 7 and 12 months.

Not always. Some smaller projects, like a Rear House Extension, may fall under 'Permitted Development Rights'. Nevertheless, the rules are complex. As part of our service, we assess your property and advise on the best and most efficient route to take.

The cost depends on the size, type, and specification of the extension. For example, a Side Return Extension will have a different cost profile to a Wrap Around Extension. Therefore, instead of giving misleading 'per square metre' rates, we provide a detailed, itemised quotation after an initial consultation.

BIM is the heart of our process. We create an intelligent 3D digital model of your home. Thanks to this, you can take a virtual tour, and we can plan every detail with precision. For you, this means less stress, no errors on site, and better value for money.

Yes, absolutely. We believe that architecture and interiors should work in perfect harmony. Therefore, our interior design team can assist with everything from layouts and lighting design to sourcing furniture and finishes, providing a complete turnkey service.

We have extensive experience working on properties with planning constraints. The process is more rigorous. However, our team knows how to prepare a design that respects the building's historic character while delivering modern functionality.

The key advantage is accountability. With the Design & Build model, a single team manages the entire process. As a result, this eliminates the risk of conflict, provides tighter control over cost and quality, and ultimately shortens the project timeline.

LET’S DISCUSS NEXT PROJECTS

The talent at Mrittik runs wide and deep. Across many markets, geographies and typologies, our team members are some of the finest professionals in the industry.. We’ve grouped our work into five categories: places, venues, spaces, experiences and events.

    Reltic is a design and build studio creating smart, beautifully crafted homes.

    Contact Info

    020 3576 2851

    office@reltic.co

    Office Address

    4th Floor, Silverstream House, 45 Fitzroy St, London W1T 6EB

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