house extensions in London
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Building the most exquisite house extensions in London requires two fundamental ingredients – a client with a dream and the right team of architects, builders and interior designers to make that dream a marble-edged, fabric-matched, open-plan, high-tech, bi-fold lit reality. Proficiency Design and Build have just such a team, so, what are your property extension dreams?

extension builders

Don’t let your home restrict your life. Extend your home to suit your lifestyle.

Elegant London House Extensions

Don’t move out, move outwards. If you have outgrown your home then extend. Today it’s far easier than ever before to build the stylish kitchen extension, fully equipped home gym, orangery relaxation room or open-plan entertaining space for family meals and parties with friends without limits. Combine this with a refurbishment of the rest of your home and you could live somewhere completely new without having to move.

home extensions
property extension
extension in north London



single extension

Traditionally the most popular extension, though it doesn’t need to be traditional in design. A single-storey rear extension can create a new room or extend an existing one.

double extension

Why just expand downstairs? With a double-storey extension, you can add space to bedrooms, create a fabulous new master, an en suite or a dressing room.

wrap around extension

As the name suggests this is an extension that wraps around two sides of your property – rear and side, to create an L-shaped extension for even more space.

side extension

A side-return utilises space between your rear rooms and your boundary fence, to extend a lounge or kitchen/dining room. Often a smaller, but cost-effective option.

End-to-End Extension Builders

Some extension builders just build, others use their decades of experience building property extensions in London and their depth of knowledge in property markets, planning authorities, challenges and solutions, materials, design ideas, technologies and trends to guide you from start to finish on your project. So, whether your property is in south or north London, whether you have grand plans like a new home construction or more modest extension aspirations, our team will go on your house extension journey with you, from end to end.


open plan kitchen extension
The Avenue, Queen's Park

Rear and side extension
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navy blue kitchen
Islington, Canonbury

Rear Extension
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Cambridge Road, Twickenham

Extension & Loft Conversion
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Hillfield Road, West Hampstead

Wrap Around Extension
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What Does a House Extension Cost

Relatively speaking, side return house extensions are less expensive than single-storey ones, which are less expensive than a wraparound or double-storey extensions. Beyond that, the cost of your extension will be governed by your tastes, your property, your planning authority and the scale of your dream home. What you can be assured of is the care we take with your budget. From the purchase of materials and the hours we work to the plans we draw up for you and the way we manage our projects, we always look for value adds and cost savings. The ability to do more with less means our home extensions are that much more spectacular once completed and our clients are that much more satisfied with our work.



To find out how we can help you to transform your home contact us today. We’re here to answer any and all questions or to book a time that’s convenient to you for one of our team member to come round to discuss your plans.


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