Home Extension Builders in Marylebone
Expert home extension builders serving Marylebone and surrounding W1G, W1U managing design, planning, and construction start to finish.
Your Local Home Extension
Specialists in
Marylebone
Planning a home extension in Marylebone comes with its own set of challenges. Properties across
W1G and W1U span everything from Georgian townhouses near Marylebone High Street to converted
Victorian mansion flats and 20th-century purpose-built blocks each with distinct structural
constraints, party wall considerations, and Westminster City Council planning requirements.
Buildaway's home extension team understands this area well, and that knowledge directly shapes
how we approach every project from the first survey.
We handle the full scope: architectural drawings, structural calculations, planning
applications, Building Control submissions, and all construction trades in-house. Whether you're
adding a rear extension to open up a ground-floor kitchen, building upward with a double-storey
addition, or making the most of a narrow side return, our team manages each stage without you
having to coordinate between separate designers and builders. If home extension cost in
Marylebone is a concern, we give you a clear breakdown upfront no surprises mid-build.
Marylebone sits within a dense urban area where even permitted development rights can be
restricted, particularly for properties near conservation boundaries around Dorset Square or the
Portman Estate. Our planners are familiar with Westminster's local policies and know when a
project can proceed under permitted development versus when a full application is needed. From
single-storey rear extensions on terrace properties near Lisson Grove to larger additions on
detached homes toward Regent's Park, Buildaway delivers home extensions in Marylebone that are
properly approved, well-built, and designed to add real value.
Our Home Extension Packages in Marylebone
Single-Storey Rear Extension
Ideal for expanding your living space. Includes structural survey, architectural drawings, groundworks and foundations, brickwork and roofing, bi-fold or sliding doors, heating installation, building regulation approval.
Side Return Extension (Most Popular)
Complete kitchen and living area transformation. Includes structural assessment, full groundworks, steelwork if required, brickwork and matching materials, glazing and doors, full insulation, electrics upgrade, flooring, building regulation approval, waste removal.
Double-Storey Extension
For those seeking maximum space addition. Includes architectural design, full structural alterations, steelwork and foundations, bespoke staircase, multiple room creation, bathroom or en-suite option, planning and building regulation handling.
Why Marylebone Homeowners Choose Buildaway
Local teams with expertise across Marylebone Village, W1, Baker Street, and West End neighbourhoods
Based in your area with local expertise and reputation.
Bespoke extension designs for Georgian homes, luxury apartments, and prime London residences
We handle everything so you don't have to worry.
Transparent and honest pricing with no hidden fees or unexpected charges.
Clear upfront pricing with no surprises along the way.
Hassle-free project management ensuring seamless, high-quality results
Meticulous craftsmanship in every aspect of your extension.
Completed projects near Marylebone High Street, Regent's Park, and Chiltern Street
Professional consultation and detailed quotes at no cost.
What's Included in Your Home Extensions Services
Everything you need for a seamless, stress-free home extension from structure to finish.
Full groundworks and structural build
Complete groundwork preparation and structural construction services.
Plumbing, electrics, and heating integration
Professional installation of all mechanical and electrical systems.
Roofing, windows, and external finish
Complete roofing, window installation and exterior finishing.
Plastering, flooring, and decorating
Professional plastering, flooring and decorating services.
Interior fit-out and finishing
Complete interior fit-out and professional finishing touches.
Project management and schedule control
Professional project management and timeline control throughout.
What Our Marylebone Clients Say
Real reviews from our satisfied customers.
"I wanted a home extension done and after meeting with several tradesmen, I decided to go with Buildaway. From my first contact with Cormac, I was in good hands. His team turned my vision into reality, communicating with me every step of the way and offered helpful suggestions which turned my space into a dream home. I could not be happier and would highly recommend their services. Thank you to the team at Buildaway."
Jackie Brown
"It was an absolute pleasure working with Cormac and the Buildaway team. Greg is an absolute star. Cormac’s communication and advice was excellent, and the organisation and sourcing of additional materials was brilliant. A truly great team, I would thoroughly recommend Buildaway if you are after a stress free and top quality home extension."
Sim Lewis
"Cormac & his team were brilliant throughout our home extension project. From scoping to completion, Cormac was always very responsive, answering any questions we had on product selection and helped us source the materials to get the best price. His team worked extremely hard and a big shoutout to Greg for his attention to detail! We couldn’t be happier with the results and would highly recommend Buildaway for any building project in the future."
Georgina Ehmcke
"We’ve had a genuinely fantastic experience with Buildaway. Cormac was ultra responsive and excellent at communicating with us throughout our project. The quality of the work was excellent - so much so, that we extended our project by adding a range of other building renovations to our original ask, each completed with care and precision. Cormac and his team clearly take a lot of pride in the service they offer - from a really helpful initial visit and quotation, to the high quality work delivered - they even thoroughly cleaned all our rooms and touched up any marks. We would highly recommend them to anyone considering getting work done. Friendly, reliable and also competitive. Thanks for all your help."
Kiran Collier
"We recently used Buildaway for a home extension at our property, along with plastering, redecoration and new spotlights installed. From start to finish the experience was smooth and well organised. Cormac was easy to deal with, communication was clear and everything ran to the agreed timelines. The team turned up when they said they would and kept the house tidy each day, which made a big difference while we were living in the property during the works. The quality of the finish is excellent. The extension looks fantastic and the space feels completely refreshed. We wouldn’t hesitate to recommend Cormac and the Buildaway team."
Helen Sivyer
"It was a pleasure working with the Buildaway team to design and build our new home extension. Cormac's enthusiasm, communication, and project management are top-notch - he went above and beyond on more than one occasion. Greg's attention to detail and dedication elevated both the experience and the result - he certainly knows his craft. In addition to the building work, Cormac replaced all the plastic switches, sockets and pull-cords in the house with brushed brass. Highly recommended and will certainly work with the Buildaway team again."
Kane Dempsey
Frequently Asked Questions
Your questions about home extensions in Marylebone, answered.
How much does a home extension cost in Marylebone?
Home extension costs in Marylebone typically start from £45,000 for a single-storey rear extension and rise to £100,000+ for double-storey builds, reflecting central London labour and material rates. We provide a detailed, itemised estimate after a free site survey so you know exactly what you're committing to.
Do you handle planning permission for home extensions in Marylebone?
Yes. Buildaway manages all planning applications and Building Control submissions across Marylebone W1G and W1U. Many properties here fall within or near Westminster conservation zones, so we assess from the outset whether your project qualifies under permitted development or needs a full application.
How long does a home extension take in Marylebone?
A single-storey extension typically takes 12–14 weeks on site. Double-storey projects run 16–20 weeks. If a planning application is needed common near Marylebone's conservation areas factor in an additional 8–12 weeks. We give you a realistic schedule from day one.
What types of home extensions does Buildaway offer in Marylebone?
We cover single-storey rear extensions, side returns, double-storey additions, wrap-around extensions, and garage conversions. Our team assesses your plot, structure, and planning constraints in Marylebone before recommending the right option for your property and budget.
Does Buildaway manage both design and construction in Marylebone?
Yes architects, structural engineers, and all trades work under one roof. No need to separately appoint a designer and then find a builder. One team, one point of contact, accountable for the finished result from first drawings to sign-off.
Do I need a party wall agreement for a home extension in Marylebone?
Most likely yes, if you share a boundary with a neighbour which is common across Marylebone's terrace and semi-detached properties. Buildaway handles the party wall notice process as part of the project, so you're not left to manage it separately.
How much is a home extension in Marylebone compared to the London average?
Marylebone sits in central London, so costs run higher than the wider London average typically 15–25% more than outer boroughs. That said, well-executed extensions in W1G and W1U add significant property value, making them a sound investment for most homeowners in the area.
We Serve Marylebone and Surrounding Areas
Find us in the heart of Marylebone. We are proud to serve our local community.
Nearby Areas We Serve
Below are some of the local areas where you can find Buildaway transforming homes.
Ready to Transform Your Extension in Marylebone?
Buildaway combines timeless design with expert craftsmanship enhancing property value across Marylebone's exclusive market.