- House Extension services
House Extensions
Create More Space with Trusted House Extension Builders
BBS Design Build Transform provides fully managed house extensions designed to create more space, improve functionality and add long-term value to your property. As an experienced design and build team, we manage every stage of the project, from design and planning to building and final finishing. We focus on quality workmanship and transparent pricing. Whether you want a single or two-storey extension, or a rear or wrap-around extension, we build practical, well-designed rooms to suit your home, lifestyle and budget.
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What Is a House Extension?
A house extension adds extra living space to your existing home, whether at the rear, side or upper floor, depending on your property and requirements.
For many homeowners, extending is a practical alternative to moving, allowing you to create a larger kitchen, additional bedrooms or bathrooms, a home office, or a more functional living space while adding long-term value to the property.
A well-designed extension can improve storage, increase natural light, strengthen the connection to the garden and make your home work better for everyday living.
A quality extension can make a real difference to how your home works day to day.
Is a House Extension the Right Option for You?
More Space for Your Home
If your existing rooms feel cramped or you cannot find enough space for your family to live comfortably, a house extension can give you the extra space you need without compromising on the location you already love.
Your Family Is Expanding
Many homeowners choose to extend, especially when they need more bedrooms, a larger kitchen or additional bathroom facilities to suit a growing family.
Need a Flexible Space or Home Office
With remote working, dedicated office space has become more important than ever. An extension can create a comfortable home office, a playroom, a bedroom for guests or a flexible multi-purpose space that evolves with your changing needs.
Want to Add Value to Your Property
Well-planned extensions can improve both the everyday usability and the market value of a property, which makes them a worthwhile long-term investment for many homeowners.
Types of House Extensions We Build
We design and build house extensions to suit your property, lifestyle and family needs.
Single-Storey House Extension
A single-storey extension to a house is ideal if you want to make a larger kitchen, dining area or family room with easy access to the garden. It is one of the most popular extension options for modern open-plan living.
Double- Storey House Extensions
Two-storey extensions provide a large amount of extra space on both floors and are commonly chosen by homeowners who need extra bedrooms, bathrooms or a separate home office. We also take on second-storey extension projects for properties where extending upwards is the most efficient use of space.
Rear House Extensions
A rear extension is a common way to build a larger kitchen and living area and improve the connection to the garden. Rear house extensions can transform underused outdoor space into bright, open-plan areas that are better suited to modern family living.
Side Return Extensions
Side return extensions make use of the often narrow space down the side of older terraced or semi-detached houses, creating a wider, more usable kitchen or dining room.
Wrap-Around Extensions
A wrap-around extension is a combination of a rear extension and a side return extension, creating a large open-plan living space with plenty of natural light and flexibility.
Pitched Roof Extensions
Many styles of property benefit from a pitched roof extension because of its traditional look, better drainage and scope for improved insulation and vaulted ceilings.
Living Room Extensions
A living room extension provides a larger, more comfortable family space, making it easier to host visitors, relax together and enjoy better natural light throughout the day.
What’s Included in Our House Extension Service?
BBS Design Build and Transform provides a fully managed extension service, taking care of every stage of the project from the initial consultation through to final handover.
Free Consultation and Property Evaluation
We start with a free consultation and a detailed assessment of your property to understand your goals, your budget and the most suitable extension options for your home.
House Extension Design & Plans
We prepare the extension design, layout options and technical drawings needed for planning applications and construction.
Fixed-Price Quotation
Before any construction begins, we provide you with a complete fixed-price quote covering the work, materials, specifications and costs.
Structural & Groundworks
We carry out all the structural work, foundations, drainage and groundworks to make sure your extension is built on a stable and compliant base.
Construction & Project Management
Our experienced site team takes care of the whole building process, managing trades, scheduling work and maintaining quality control throughout the project.
Interior Finishing
We complete all internal work, including plastering, flooring, electrical and plumbing installation, decoration and final finishing details.
Final Inspection & Handover
Before handover, we carry out a full quality inspection, fix any snagging issues and make sure your new extension is ready for you.
House Extension Services in Your Area
As experienced builders, we provide fully managed house extension services across London. Explore our dedicated location pages to learn more about local project experience, planning considerations and the extension options available in your area.
Bespoke house extensions in Harrow, including single-storey, rear and wrap-around styles, with fully managed design, planning, construction and interior finishing.
An experienced team delivering fully managed house extensions across London, including rear, side and wrap-around styles, with expert design, planning and construction support.
Create more space with expertly designed house extensions in Edgware, including open-plan kitchens, additional bedrooms and modern family living areas.
Frequently Asked Questions
What is an extension to a house?
An extension to a house is a new structure added to the existing property to create additional living space. This can include rear, side, wrap-around, or upper-floor extensions, depending on the available space and your requirements.
How much does building an extension cost?
The cost of building an extension depends on the size of the extension, the complexity of the design, structural requirements, ground conditions, and the level of finish you choose. We provide detailed fixed-price quotations after an initial property survey.
How much does a side return extension cost?
A side return extension is often a cost-effective way to increase kitchen and dining space in terraced or semi-detached homes. The final cost will depend on the width and length of the extension, structural alterations, glazing, and the specification of the finishes.
How much does a two-storey extension cost?
A two-storey extension provides additional space across both floors and is usually more cost-effective per square metre than building two separate extensions. The overall cost depends on the size of the extension, structural work, roof design, and internal finishes.
How to build an extension?
Building an extension typically involves a consultation, property survey, design and planning, obtaining any required approvals, structural and groundwork preparation, construction, and final finishing. BBS Design Build Transform manages the entire process from design through to completion.
What is the cheapest way to extend a house?
In many cases, a simple single-storey rear extension is the most affordable extension option because it usually involves less structural work and a simpler construction process. The best solution will depend on your property layout, budget, and long-term plans for the home.
Testimonials
Start Your House Extension Project
Whether you’re planning a single-storey extension, a larger family extension or a complete design and build project, our team is here to help.
We offer free consultations, fixed-price quotations and expert guidance from planning through to completion, helping you create a home that is more spacious, functional and valuable.
Let’s discuss your extension ideas and explore the best way to create the extra space your family needs, with professional advice, transparent pricing and high-quality workmanship from an experienced local team. Contact us today!
