Extension builders in Mayfair

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.6 (21 reviews)

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Some of our top rated extension builders in Mayfair

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HM construction
No reviews yet
Extension Builder in Mayfair
H.Muzaci Contractor is a well-established building company with over 25 years of experience in the construction and renovation industry. We specialise in home renovations, extensions, refurbishments, and general building work, delivering high-quality results from start to finish. We pride ourselves on excellent workmanship, reliability, and attention to detail, no matter the size of the job. From initial planning through to completion, we work closely with our clients to ensure projects are delivered on time, within budget, and to a high standard. Customer satisfaction is at the heart of everything we do. We are tidy, respectful, and committed to clear communication throughout the project. Much of our work comes from repeat customers and recommendations, which reflects the quality and trust we’ve built over the years. Clients from all over City of London with references (Mayfair, Chelsea, Portsman Square). If you’re looking for an experienced, honest, and professional builder, H&M Construction would be happy to help.
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BOTNARI CONSTRUCTION
Rating: 4.4 out of 5
Extension Builder in Mayfair
We provide a service of maximum quality and client satisfaction . Having over 25 years experience in the field we have completed jobs big and small to the best standard .
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Latest review:
Electrical- 26 Jul 2026
Genuinely one of the worst builders we have come across. David rewired the flat and Stefan plastered the hallway. David is NOT qualified as an electrician and cut corners wherever he could. David leveraged us for money mid job and in the end left the job without finishing and without providing a certificate. David ran cables behind door frames (awful idea), got the cheapest material, forgot where holes were for spotlights and switches among many issues which meant we had to constantly ask our builders to fill the holes and make good. Stefan did the hallway plastering without putting on mesh. The plaster cracked within 2 weeks and the paint keeps cracking and will be a constant problem. When asked to come back and fix the issue - he point blank refused. They were the cheapest quote but we really hope we had gone to someone else
LIVAHAUS
Rating: 5 out of 5
Extension Builder in Mayfair
We are a professional team and we are very responsible, punctual and on time with our work .
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Latest review:
Tiling- 16 Feb 2026
Luis did an excellent job on my bathroom. He had to do a lot of prep work before starting the tiling, including rebuilding the floor and repairing the walls. At every stage he explained what needed to be done, ensured that I wanted to go ahead, listed the materials that would be needed, and the cost. It made a huge different to me that Luis was willing to source and purchase all materials; he checked in with me from the suppliers as to choice and cost, and sent receipts for every penny. I cannot recommend him highly enough, for his knowledge and expertise, his honesty and hard work, and also for being such a lovely person, nothing is too much trouble. I am delighted with my new bathroom, and am planning more home improvements with Luis, when he is free again!
All in one builders
Rating: 5 out of 5
Extension Builder in Mayfair
At All In One Builders we take pride in being your trusted partner for all your construction needs. With a wealth of experience and a commitment to excellence, we specialise in a wide range of building services tailored to meet your unique requirements.
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Latest review:
Akash made sure the job was complete exactly how he said it would be, he provided reliability during the installation of our kitchen and answered all questions very professionally. The builders were well aware of the conversations my mother and I had with Akash and so put our mind at ease. The installation itself was very quick (the tear down was very much completed in a few hours) and installed over the weekend. They were very hygiene aware and set up a cover between the kitchen and the rest of our house and didn’t disrupt our home living. They cleaned up before they were gone to very high standards without us even asking them too, all I’m sure is due to Akash’s excellent organisation skills.
Ivor
Rating: 5 out of 5
Extension Builder in Mayfair
refurbishment,rear &side extensions,loft conversions+all the 2nd fix internall works-kitchen,plumbing,electrical,drainage,tilling,glazing,rendering,plastering,painting
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Latest review:
LargeGround floor extension, conversion of a bedroom to second bathroom, loft conversion, front garden paving , rear garden natural stone fitting, full refurbished of 5 bedroom house, 2 bathrooms, 2 living rooms and office, 1 large garden shed builded
Memaar Construction
Rating: 4.8 out of 5
Extension Builder in Mayfair
Our Expertise MEMAAR Construction is a business specializing in refurbishment, renovation, extension, painting, flooring, decoration, tiling, and demolition services. With a commitment to quality craftsmanship and a customer-centric approach, MEMAAR emphasises personalised service and priorities client needs. The business is supported by an expert team in the construction industry and aims to use sustainable practices while offering affordable pricing without compromising quality. Refurbishment is about improving or refreshing existing structures without making major changes to the layout. It often involves repairs, repainting, replacing fixtures, or upgrading finishes to bring a building back to a good condition. For example: updating office interiors, repairing walls, replacing windows, or modernizing outdated spaces.
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Latest review:
Extensions- 16 Jul 2026
They did fantastic Job.
HARMANRAJ CONSTRUCTION
Rating: 4.9 out of 5
Extension Builder in Mayfair
Business Name: Harman Raj Constructions Ltd About Us: At Harman Raj Constructions Ltd, we bring 7 years of experience in roofing, building extensions, plastering, driveways, and fencing. We take pride in delivering high-quality craftsmanship for every project, whether big or small. Why Choose Us? • Expertise You Can Trust: Our 7 years in the construction industry mean we have the skills to handle a wide range of projects. • Customer-Focused: Your satisfaction drives everything we do. We work closely with you to ensure the final result matches your vision. • Specialized Skills: From roofing and extensions to plastering and fencing, our expertise ensures excellent results. • Quality & Reliability: We deliver on time, within budget, and without compromising on quality. Services We Offer: • Roofing installation, repairs, and maintenance • Building extensions and renovations • Expert plastering • Driveway construction • Fencing installation and repair Contact us today for a free quote and let us bring your construction ideas to life!
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Latest review:
Plastering- 11 Apr 2026
Absolutely thrilled with the work carried out by Harman. The skimming has been completed to an exceptionally high standard - the finish is incredibly smooth and completely seamless. Harman and his colleague were professional throughout: tidy, courteous, and very polite. They took great care to properly protect and cover the surrounding areas, leaving everything clean and intact once the job was done. What really stood out is their attention to detail and commitment to getting everything perfect - even offering to return for any final finishing touches if needed. I honestly couldn’t recommend them highly enough. Brilliant job from start to finish.
VANSH CONSTRUCTIONS LIMITED
Rating: 5 out of 5
Extension Builder in Mayfair
VANSH CONSTRUCTIONS LIMITED have over 10 years experience, and with many years experience in the building trade. We are a professional team and are reliable builders operating in London and the wider area. We take great pride in all work which we undertake, taking great care to make sure that our client’s needs are met in a meticulous and professional manner. We are specialists in driveways and making extensions and refurbishment of homes which we give our best to make good Quality.
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Latest review:
Driveways (Paved & Loose)- 6 Feb 2025
I am very happy.Done job early and clearly.
Concorde construction Ltd
Rating: 5 out of 5
Extension Builder in Mayfair
We cover all types of construction. From your small handyman jobs to building large extensions and summer houses. We specialise in all types of carpentry, bricklaying and decorating. We can take care of all of your building needs with plenty of recommendations. Look forward to hearing from you.
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Latest review:
Extensions- 5 Oct 2022
I am very pleased with the work Josh and his team did in building my rear extension. They were a friendly and hard working bunch and very respectful of my space. Josh did a great job in project managing the work and making sure things were progressing as planned. Any snagging items were dealt with promptly. I would hire them again if required and recommend them to anyone who wanted to have building work done.
Plastering and Rendering
Rating: 5 out of 5
Extension Builder in Mayfair
plasterering and Renderering specialist, K-rend - silicone render - insulations, EWI system, Micro cement. drylining, and full refurbishment. Over 20 years experience.
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Latest review:
Plastering- 7 Aug 2023
Festim was efficient, punctual and did a very nice job rendering my wall. Highly recommended.
Al Costa Construction LTD
Rating: 5 out of 5
Extension Builder in Mayfair
WHO ARE WE? With over 25 YEARS OF EXPERIENCE with AL Costa Construction, you will find the best services provided by professionals that understand and have the knowledge of the process of construction and renovation that best suits your project. It does not matter how big is your project, we work with excellence and dedication to reach perfect results. We try to merge trends with innovating materials and processes in each project, in order to achieve high standards results in every project. OUR TEAM Our team is formed by professionals that are able to perform your project with quality, so your dream project can get out of paper and become a dream come true. Our professionals are always concern with the client’s wishes and try to combine it with them expertise, in order to achieve a final result above expectations, functional and with premium quality. OUR GOAL We try to come up with the best solutions in construction and renovation to provide ours clients an excellent experience. Our main goal is to offer services that match ours clients needs, with an excellent quality.
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Latest review:
Hard Flooring- 11 Dec 2018
Did my 3 bedroom house wooden flooring for full house. Had a wonderful experience with Alex, great job and completed on time with good standards. He gave some good suggestions which improved the quality and neatness of work. highly recommending will work with him again.
Keiss
Rating: 4.5 out of 5
Extension Builder in Mayfair
Experienced and reliable carpenter and builder offering exceptional craftsmanship Whether it's creating custom furniture or managing construction projects, I prioritise attention to detail and exceeding expectations.. Dedicated to delivering high-quality work on-time and within budget. Strong communication skills, attention to detail, and a commitment to customer satisfaction. Let's discuss your project and bring your vision to life.
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Latest review:
Joinery & Cabinet Making- 17 Feb 2025
Keiss took the deposit and did not respond to my call after promising that he will come today to fix my wardrobe.
AT Line Construction
Rating: 5 out of 5
Extension Builder in Mayfair
We are a limited company with many years experinece at construction and usually undertake medium to large size projects like refurbishment, bathroom restoration, loft conversation, extensions and general refurbishment. With high end quality.
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Latest review:
Extensions- 17 Nov 2022
AT Line Construction built our extension and worked on the remodel of the inside of our flat. We are extremely happy with the results. Adison and his team are very professional and friendly. They were able to deal with any changes and problems that came up quickly and sensitively. Part of the build was to renovate a small disused swimming pool - this was a tricky job, and they were able to help us creat an amazing pool. We would definitely recommend them.
Ndoci construction ltd
No reviews yet
Extension Builder in Mayfair
We are a dedicated construction and renovation company delivering high-quality work across residential and commercial projects. From small repairs to full-scale builds, we handle every stage with precision, reliability, and attention to detail. Our goal is simple: to bring your vision to life on time, on budget, and to the highest standard.
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Bricklayer
Rating: 5 out of 5
Extension Builder in Mayfair
Brickwork . New build, extension . Garage
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Latest review:
Bricklaying- 10 Jul 2023
I am very pleased with the work done Excellent clean job Mr Bicol has carried out
Dominik Dudziak
No reviews yet
Extension Builder in Mayfair
I am a skilled builder with many years of experience. If you are looking for someone to plaster your kitchen, bathroom, or other room, please do not hesitate to contact me. I am happy to help.
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4.6

Top rated Extension Builders

Our Extension Builders in Mayfair, are rated 4.6 out of 5 based on 21 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.