Extension Builders in Mayfair

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.2 (20 reviews)

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Some of our top rated extension builders in Mayfair

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James Murdoch
Rating: 5 out of 5
Extension Builder in Mayfair
Construction company with 27 years experience in the industry between us and a team of other qualified tradespeople necessary to undertake projects.We are new to this site so please ask us to provide you with reference from previous clients. We have experience in timber frame homes, apartment blocks, extensions, renovations and commercial works.We take great pride in our work and make sure every job is completed to the highest of standards on time and on budget. Our aim is your satisfaction.
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Latest review:
Carpentry- 31 May 2017
Was really impressed with these guys. Helped me order the correct garden door and then went to pick up extra bits when the order didn't turn up correctly, for no extra cost and couldn't have been nicer about it, even though it was a pain for them. Really cheerful and helpful - nothing was too much trouble. Would use them again, for sure.
4 You Residential Limited
Rating: 5 out of 5
Extension Builder in Mayfair
We have over 18 years of experience in residential and commercial refurbishment. We are skilled team of managers, architects, builders and craftsmen, competitively priced and flexible to suit your needs. We specialise in building basements, extensions, loft conversions and carry out full house refurbishments as well as working on smaller projects like kitchens, bathrooms, joinery and fit-out. Our team is energetic, fully insured, certified and recommended by long list of happy clients.
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Latest review:
Groundwork & Foundations- 18 Jul 2019
My wife and I have been truly impressed by Victor and Tom's quick turnaround and willingness to get the job done to an extremely high standard. Their men were friendly, efficient and tidy which is invaluable when taking on any new and daunting property project. As a result of their efficiency we are hoping to work with Victor and his team again in the coming months and would highly recommend them to anyone looking for a reliable and professional contractor.
Bare Interiors
Rating: 5 out of 5
Extension Builder in Mayfair
We are a small company of 5 people (with more than 15-20 years of experience each) having 2 vans carrying all the tools needed. We can provide you with any services from kitchen / bathroom fitting , to full house renovations and extension builds.
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Latest review:
Bathroom Fitting- 9 Feb 2019
Alexandros did an exceptional job with our bathroom. As it was our first major renovation we were very anxious about the whole process but Alexandros made everything very easy and smooth from the beginning until the end. Alexandros has a lot of experience and he is full of ideas and good suggestions. The new bathroom looks amazing and we could not have chosen better than Alexandros. Alexandros was very helpful throughout the whole process. I would highly recommend Alexandros to anyone and we will definitely use his services in the future.
Sam's Building Maintenance and Constructions Ltd
Rating: 5 out of 5
Extension Builder in Mayfair
Sam's Building Maintenance and Construction Ltd has more than 25 years experience in First and Second Fix carpentry, Kitchen installation, extension, loft conversion and general refurbishment work. We deliver quality services to meet customers' specifications and within stipulated deadlines .
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Latest review:
Sam did 5 and half meter kitchen, with large shower and laundry rooms extension for me. He is of very good character, worked professionally, reliable and his work was good.
ALT’s Builders
Rating: 5 out of 5
Extension Builder in Mayfair
We are a family run business with more than a decade of experience. At ALT’s Builders Ltd we pride ourselves on an efficient and friendly service, and achieve 100% costumer satisfaction ethic. So no matter how big or small your job is we can help. ALT’s Builders Limited is a leading and reputable Construction Company serving around London Ever since we opened for business, we’ve taken a comprehensive approach to construction industry, providing our clients with a wide range of services to cover their needs. our clients are our Number one priority and we go extra mile to make sure they’re completely satisfied. we stand by the excellence of our work and provide clients with personalized attention based on their specific needs. With this service, we’re fully prepared to tackle even the most complex projects and stand by the exceptional quality of our work.
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Latest review:
Loft Conversion- 6 Jul 2026
Brief was a loft conversion + our front driveway completed in East Dulwich, South East London in Q1 2026 and we’d happily recommend Altin from ALTs builders if your in need of a good quality builder: - Competitive price - Good comms throughout - Hard working and extra hours as required to keep project on time - Highly reviewed on checkatrade.com / mybuilder.com company profiles - Overall professional job which we are super happy with When finishing up with us he then started another project down the road off the back of our recommendation and I know they are also very happy with him as a builder!
BSM Interior Ltd
Rating: 4.8 out of 5
Extension Builder in Mayfair
Your search for qualified and skilled builders ends here. Made Construction Simple is a team of licensed and insured specialists builders in London with over one decades of combined experience. From extensive loft conversion, extension,refurbishments to bathroom and kitchen renovations, we offer a wide range of services. You can rest assured that we have the expertise to efficiently handle your construction project. Good and dependable work isn’t possible without the necessary qualifications. Every professional on our team is qualified and highly experienced. We undertake all aspects of planning, building and construction services according to the highest standards of workmanship. We prioritise quality, safety and consistency at every step of the way. Our services are compliant with local authority laws and government regulations. We pride ourselves on our exceptional attention to detail. In addition to superior functionality and durability, we don’t forget about how the final result looks. We strive to deliver the best of structural integrity and aesthetics.   Our professional builders go above and beyond to earn your trust. We are dedicated to starting and completing jobs on time for 100% customer satisfaction. If there are any unforeseen delays, you will be promptly informed and kept in the loop. We also ensure that every project is within the specified budget.
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Latest review:
Kitchen Fitting- 4 Aug 2026
Bled and his team was absolutely amazing and fair. He use all his knowledge and install my kitchen in best way can imagine. He install my kitchen units, worktop, all appliances, relocated washing machine, installed kitchen splash back and repositioning of sockets and fuse spurs. I definitely recommend Bled and I will definitely use him again near future. Thanks Bled!
BRH
Rating: 5 out of 5
Extension Builder in Mayfair
We are a professional property repair, maintenance and renovation company, committed to providing high-quality workmanship and reliable service to homeowners, landlords and property managers. With over 10 years of experience, we specialise in a wide range of property improvement and maintenance services, including plastering, plasterboarding, painting and decorating, tiling, carpentry, bathroom and kitchen refurbishments, roofing, repairs and general property maintenance. Whether it’s a small repair, ongoing maintenance or a complete refurbishment, we take pride in delivering a professional finish, paying close attention to detail and completing every job to a high standard. Customer satisfaction is at the heart of our business. We believe in honest communication, clear quotations, reliable workmanship and treating every property with care and respect. We are happy to discuss your requirements, provide a clear quotation and answer any questions before work begins. No advance payment required. Payment is agreed upon completion of the work or in stages for larger projects. We look forward to helping you improve, maintain and protect your property.
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Latest review:
Plastering- 7 Sep 2026
Did as they said very good very happy of the progress and end Project
Bass Construction Ltd
Rating: 5 out of 5
Extension Builder in Mayfair
A multidisciplinary construction firm with a focus on custom construction, Bass Construction/Design was established in 2013. Our team provides services for residential and commercial properties from the planning to construction stages with the goal of creating spaces where functionality and aesthetics coexist.
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Latest review:
Extensive work including a double height extension, reconfigured layout on two floors, large area of glazing, roof lights, kitchen and bathroom fitting, laying of a patio and other ancillary work. The work was carried out by Bruno, Roberto and the team to the highest standards with great attention to detail and with care. The completed project was beyond our expectations.
AJ REFURB SPECIALIST LTD
Rating: 5 out of 5
Extension Builder in Mayfair
With over 20 years of experience in the building industry, we have honed our skills to handle projects of all sizes. Our commitment to quality and craftsmanship ensures that every job is completed to the highest standards,
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Latest review:
Bathroom Fitting- 21 Jun 2025
Great company, attention to detail & Joe went over & above. I would recommend them highly. Thanks for such an awesome renovation, hope to do future projects with you 😊
Rcm Buildrs
Rating: 5 out of 5
Extension Builder in Mayfair
RCM Builders is an insured construction company which offers a multitude of services. Loft conversions, extensions, painting, plastering, fencing, building renovations, and bricklaying are a few specialities we covers. We have over 28 years worth of experience and are well versed in providing high quality work, great customer service, great costumer satisfaction and great communication.
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Latest review:
Conversions - General- 7 Mar 2023
Have completed the job extremely well. Did a new door opening. Door fittings and plaster work . Very good finish. On time. Polite. Very pleased. Would hire again.
Patrick JR
Rating: 5 out of 5
Extension Builder in Mayfair
Experienced Tradesman who enjoys providing a friendly and reliable service to customers. No job too small from Demolition and groundwork’s to first fix of structures to second fix finishing jobs such as hanging TVs and mirrors. Please get in touch for a no obligation quote and estimated timescale.
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Latest review:
Handyman- 4 Aug 2021
Great during the pandemic, able to change appointment due to isolation. Job completed in a timely manner and work space left clean. Job completed a month ago and still perfect. Thanks
shalom property development ltd
Rating: 5 out of 5
Extension Builder in Mayfair
Shalom Property Development ltd is a small construction company based in the Croydon area. We specialize in property refurbishment, house extensions, loft conversions, garage conversions, etc. We also undertake projects like plastering, painting/decorating, electricity, plumbing, tiling, flooring(laminate, wood, bamboo), bricklaying.
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Latest review:
Plastering- 6 May 2025
Amazing guys. Hardworking, tidy, professional. They worked in our house for 3 months and we were super happy with the work and everything. We invited them to do more work later on. 100% probably the most sincere and trustworthy builders we met. Only them. No one else from now on.
DF Construction
Rating: 5 out of 5
Extension Builder in Mayfair
DFGC are commercial and residential refurbishment specialists. We've created partnerships with high profile companies to complete large scale projects, in the South East of England - shown on my profile. We are known for a wide range of undertakings, from complete refurbishments, extensions, bathrooms, driveways, to name a few. There's very little we can't do, with regards to construction. We're a one stop shop for all your construction needs - we can take your vision and make it a reality.
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Latest review:
Extensions- 13 Dec 2021
Couldn't recommend Domi & Emile enough. They have great building knowledge and kept us informed and up to date throughout the whole building process. The job was finished to a high standard and they even came back free of charge to tie up a few snags a few weeks later. Great builders and a great team!
Wall Done SP
Rating: 5 out of 5
Extension Builder in Mayfair
We believe your home should evolve with your lifestyle. Whether you're expanding your living space with a loft extension or completely renovating your property, we turn your ideas into reality.
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RT Build
Rating: 5 out of 5
Extension Builder in Mayfair
We are a family run small company with 20 years on the market.We specialize in bathroom ,kitchen and general building refurbishments.We offer high quality service for a reasonable price with great attention to details. Your satisfaction is our top priority.We are looking forward to doing new project with you.
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Latest review:
Bathroom Fitting- 27 Dec 2025
Rafal did everything as expected. Many thanks for his commitment and professionalism.
Greg Building Services
Rating: 5 out of 5
Extension Builder in Mayfair
I’m professional multi tasking builder with 21 years of experience in renovation and maintenance of residential properties in London
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Latest review:
Handyman- 8 Aug 2023
Excellent work repairing loose bathroom tiles, floorboards and crack in wall. Highly recommended.

4.2

Top rated Extension Builders

Our Extension Builders in Mayfair, are rated 4.2 out of 5 based on 20 reviews from customers like you.

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What types of services are offered by local extension builders in Mayfair?

Building an extension is a major milestone for any home. It’s not just about adding extra space, it’s a big step that can transform how you live day to day, opening up new possibilities for comfort, lifestyle, and family needs.

This is why it’s so important to find the right extension builders in Mayfair for you. They can help with a variety of tasks and projects, including:

Extending your home with an extra room
Two+ storey extensions
Adding partition walls to create more rooms
Building annexes or external structures

To find the right extension builder near you, simply post your job on MyBuilder. Explain the type of help you’re looking for, and then home extension builders in Mayfair who are available and interested can respond to your post.

Browse profiles, read customer reviews and get quotes from your chosen Mayfair extension builders, all before you decide who to hire.

What are the hourly rates of extension builders in Mayfair?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Mayfair will charge between £16 and £42 per hour.

Single-storey rear extensions cost between £20,000 and £60,000 depending on size and finish.
The cost of double-storey extensions, which add more space and value, can range from £100,000 to over £170,000.
Larger wrap-around extensions that combine multiple extension types can range from £40,000 to over £120,000.

The cost of an extension will vary depending on your property. For instance, extending in certain areas may require structural adjustments to ensure stability, which can increase your material and labour costs.

To get an accurate price for your home extension, request detailed quotes from several Mayfair extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Mayfair home extension project is likely to cost.

Find extension builders in Mayfair with MyBuilder

Hiring the right extension builder in Mayfair with MyBuilder couldn’t be easier. Just follow these simple steps:

Step 1: Post your extension project on MyBuilder

Whether you’re planning a single-storey extension, a loft conversion, or adding a new room, post your job on MyBuilder to find local Mayfair extension builders. Once your job is live, we’ll share it with home extension builders in Mayfair who can express their interest.

Step 2: Compare different extension builders in Mayfair

When you start receiving interest, review profiles of local Mayfair extension builders, check their previous work, and read real customer reviews. Ask about timelines, materials, and request detailed quotes.

Step 3: Hire Mayfair extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Mayfair, compare their experience, guarantees, and costs before choosing who to hire.

You’ll also have confidence knowing that every tradesperson on MyBuilder is verified through several checks, including:

ID verification: When a tradesperson joins MyBuilder, we ask for a valid ID, such as a passport, ID card, or eIDAS certificate.
Company verification: For tradespeople operating under a company, we make sure every tradesperson has a registered business.

Did you know? Our continuous monitoring and complaints process ensures that tradespeople who don’t meet our standards are promptly removed from MyBuilder’s platform.

Mayfair extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Mayfair extension builder before hiring?

Before hiring an extension builder in Mayfair or extension building company in Mayfair, ask a few key questions to make sure you’re choosing the right professional for your home extension project.

What qualifications and experience do you have as an extension builder in Mayfair?

An extension builder in Mayfair should have a strong track record with similar projects and relevant building qualifications or trade memberships, such as the Federation of Master Builders (FMB) or TrustMark.

Will my home extension meet all building regulations and planning requirements?

Your Mayfair extension builder should ensure the project complies with Building Regulations and, where necessary, handle or assist with planning permissions. Ask how they manage building control inspections and what documentation you’ll receive once the project is complete.

What experience do you have with similar extensions in Mayfair?

Ask to see examples of their previous work, or view examples of their work on MyBuilder. Ideally projects similar to yours in scale and design. This helps you assess the Mayfair extension builder’s ability to deliver a result that meets your expectations.

How long will the extension take to complete?

Extension project timelines can vary depending on size, complexity, and weather. A typical single-storey extension might take around 8 - 12 weeks. Request a detailed schedule so you know what to expect and when key milestones will be reached.

Do you offer a guarantee for your work? Most Mayfair extension builders offer a guarantee or warranty on their work, often between 1 and 10 years depending on the project and materials used. This gives you assurance that any issues will be resolved after completion.

If you still have questions about the professional you are looking to hire, we have a full detailed guide on hiring the right builder here.

FAQ: Common questions about home extensions in Mayfair

Can an extension builder in Mayfair help with planning permission?

Yes, many extension builders in Mayfair can guide you through the planning process. They can help prepare drawings, advise on local requirements, and liaise with your local council to ensure your project meets all necessary regulations.

Can an extension builder in Mayfair handle everything from design to construction?

Many Mayfair extension builders offer full design-and-build services, managing both the architectural planning and construction stages. Ask your builder whether they can provide a complete package or if you’ll need to hire an architect or designer separately.

Will an extension builder in Mayfair help with materials and finishes?

Yes, most extension builders in Mayfair can source materials and offer advice on finishes that suit your design and budget. You can also choose to supply certain materials yourself, just make sure this is agreed upon before work starts.