Extension Builders in Westminster

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.1 (18 reviews)

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Some of our top rated extension builders in Westminster

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Done By Tom Ltd
Rating: 5 out of 5
Extension Builder in Westminster
Welcome to Done by Tom – we offer a completely bespoke design and build service for the London private sector. If you’re looking for clever, stunning and energy-efficient construction as well as interior design, we are it. At Done by Tom, we’ve come up with a unique success formula when it comes to memorable design and construction: combining the interior design, architecture and construction process into one seamless dream to deliver according to our clients vision.
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Latest review:
Fireplaces & Flues- 13 Nov 2017
i was so so happy with the service completed by done by tom. I had a really urgent last minute job and they were able to complete all the work to a really high standard and with a great price. I would trust them to do any building work in my house and am happy to have found a trusted builder for future works. Would recommend to anyone
G.B
Rating: 5 out of 5
Extension Builder in Westminster
Refurbishment Extension Loft conversion
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Latest review:
Plastering- 29 May 2026
Great job. Hired to plasterboard underneath the stairs. The space was awkward and didnt think anyone could sort it but Gaz did a great job and now I can use the space as intended. Will definitely be hiring for more jobs and would recommend. :)
2AM Construction
Rating: 4.6 out of 5
Extension Builder in Westminster
Hi this is Ali I am electrical contractors with over 10 years of experience who covers all types of electrical work. I do both domestic and commercial installations, rewiring, fault finding, repairing, fire alarms, smoke alarms, emergency lighting, EICR Certificate
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Latest review:
Electrical- 3 Oct 2025
went very well - almost superb, maybe of 5 stars 4.9.
RESSI LTD
Rating: 5 out of 5
Extension Builder in Westminster
RESSI is a London-based building contractor, specialising in refurbishing and building lofts and extensions. We are a family run business with a focus on spending time with our clients to make the experience worthy of the investment. We have a great eye for detail and can help you with all your choices such as kitchens, joinery (our own), sanitary ware and anything else you might need.
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Latest review:
It is stunning. Loved working with Ressi. The end result is perfect. It is our dream home. They listen well and want to do what is best for all
Extension Kings Ltd
Rating: 5 out of 5
Extension Builder in Westminster
I've been working in building trade for over 20 years , I can undertake any job small and big from foundations to the roof and anything between. I can provide any references and I have insurance of £5 million. Me and my team take pride at what we do and we do it first time right .our work is second to none , and proof of that is that you don’t pay anything upfront till you are fully satisfied with the quality.
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Latest review:
Extensions- 8 Oct 2018
Alban completed a lateral kitchen extension for me in west London. Very happy with the results and to add my name to others that have given 100% positive feedback. What I particularly liked - (1) Alban took great care to protect the rest of my house while working (protection, covers etc), (2) his team were friendly and polite to neighbours. Building works are always noisy and disruptive, they kept others 'on side' and (3) they worked to the timing and schedule agreed (4) they cleaned up, every single day (5) they worked to a high standard and corrected for any issues, despite my inevitable last minute changes. Wish him and team best success... happy to recommend. Rob
Njurabuild limited
Rating: 4.8 out of 5
Extension Builder in Westminster
20 years experience. 4th Generation Builder Full Public liability insurance Listed works: General maintenance Extensions Groundwork Painting and decorating Plastering All the building works
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Latest review:
Extensions- 3 May 2023
The work is scheduled to begin in July due to Njurabuild's prior commitments. Meetings regarding this have proved very positive and helpful, and I look forward to the eventual outcome.
Teimourazi Bachsoliani
Rating: 5 out of 5
Extension Builder in Westminster
Hi, my name is Temo. Our team has combined experience of more than 20 years and we have an excellent reputation, for high quality work, tidy finish and friendly service. My team does all types of jobs including extension, loft conversion, full refurbishment. We always deliver best quality job for a reasonable price.
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Latest review:
Conversions - General- 23 Jul 2025
I recently had the pleasure of working with Teimo and his team on a full renovation of a probate house, and I couldn't be happier with the results. The entire house needed a complete overhaul, including two new bathrooms, a kitchen extension, new doors, skirting, walls, plumbing, electrics, as well as front garden paving, a brick wall, and back garden fencing. The quality of the work is outstanding. Teimo and his team take immense pride in everything they do, and it really shows in the final product. They are not only highly skilled but also incredibly polite and tidy, ensuring the worksite remained clean throughout. They worked hard, from 8:30 AM to 5:30 PM every day, and completed the project on time without any issues. What truly stands out about Teimo is his honesty and clear communication. He’s upfront about everything, and you can trust that the price you’re quoted is the price you’ll pay—there are no surprise cost increases along the way I highly recommend Teimo and his team
Solid Group Renovations
Rating: 5 out of 5
Extension Builder in Westminster
Hello, we are professional team with much experience and knowledge. We specialize in refurbishing properties, whether it is HMO conversion, loft conversion, house extension or complete refurbishment. I work closely with my clients and I am easy to contact at all times. Our team make sure that you are in control every step of the way to achieve your dream renovation project.
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Latest review:
Bathroom Fitting- 20 May 2026
Saba and Zura were outstanding and an absolute joy to work with on this project. I initially hired them to fit my new bathroom, and I was so impressed with the quality of their work, that I asked them to complete the rest of my renovations, which included new flooring, decorating, installing wall panels and fitting a new kitchen. All of it were completed to the highest standards and ahead of schedule.They are very professional, friendly, hard working and communicates so well. This is my third project, and by far the most stress free one, I couldn't recommend them enough! Thank you guys
Acelux Ltd
Rating: 5 out of 5
Extension Builder in Westminster
We offer a wide range services from a minor works, extensions to a complete refurbishment. We are Electrical Certified Gas Safe Certified Trust Mark Government approved Contractor. Considerate Construction Member A family run business
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Latest review:
Acelux did a brilliant job on our office refurb. We were very happy with the work completed as well as the service. They were able to come out of office hours during the bank holiday weekend, finish on time, and even stopped back in on Tuesday to make sure we were all happy with the works.
Firfield Property Services Ltd
Rating: 5 out of 5
Extension Builder in Westminster
We specialise in renovations & refurbishments of residential properties in London. Our team arrive on time, are highly professional & polite and leave your home in pristine condition. **Free quotation and advice **All work guaranteed **Fully insured ** References available
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Latest review:
Handyman- 26 Aug 2014
The job went very smoothly and there were no problems. Twana, from Mark's team was punctual, professional and did the job exactly how we wanted it. We will certainly be using them again.
H&S Construction Ltd
Rating: 5 out of 5
Extension Builder in Westminster
H&S Building Contractors is a leading construction company based in London and Essex, specialising in both residential and commercial projects. We are dedicated to delivering high-quality craftsmanship and innovative building solutions tailored to each client’s needs. With a strong focus on sustainability and client satisfaction, we transform visions into reality while ensuring every project is completed on time and within budget. Our experienced team works diligently to maintain transparent communication, uphold the highest safety standards, and deliver exceptional results at every stage of the construction process.
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Latest review:
Shumon and his team did plastering, painting and decorating and they built me a fireplace and fitted in a fire. I would highly recommend him - he is absolutely brilliant and did a great job - they take a lot of pride in what they do, very trustworthy, and I am looking to have them back about Christmas time to do some bathroom work. They are very good value for money.
MM
Rating: 5 out of 5
Extension Builder in Westminster
We are a highly experienced kitchen and bathroom design and installation company with over 20 years of proven expertise in delivering exceptional results. We provide a comprehensive, end-to-end service—from detailed consultation and bespoke design through to precise, high-quality installation—or a dedicated installation service tailored to your specific needs. Our work is defined by technical accuracy, refined craftsmanship, and a deep understanding of both aesthetics and functionality. We deliver bespoke kitchen and bathroom solutions across a full spectrum, from well-specified standard projects to luxury, high-end installations, all executed with exacting standards and attention to detail. Operating throughout London and the surrounding areas, we are committed to delivering a consistently high level of service, underpinned by expert guidance and industry knowledge. Every project is approached with a structured, client-focused process, ensuring clear communication, efficient delivery, and outstanding results. Regardless of the size or complexity of the project, we work in close partnership with our clients to accurately interpret their vision and requirements—translating them into expertly crafted spaces that meet the highest professional standards.
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Latest review:
We initially hired Michael to convert a bathroom into an office. After meeting him and discussing our longer-term plans, we quickly felt confident moving forward with him on much wider renovation works across the property. Michael worked closely with us throughout the entire process—from early ideas and structural planning through to execution. He consistently provided insightful, practical advice that added real value. His ability to anticipate issues early not only prevented problems but also helped us save money by refining the plans to maximise our goals and avoid unnecessary costs. Michael’s broad knowledge and skill set were hugely beneficial on a project of this size and within a tight budget. He made the process far less stressful and, at times, genuinely enjoyable. He kept me informed and involved at every stage, which gave me a great deal of confidence in both the quality of the work and the decisions being made throughout. Michael helped us renovate every corner of our four-bedroom maisonette in West London—from bathrooms and structural opening-up works to a full kitchen renovation, hard landscaping, flooring, and carpentry. The list goes on. His wide skill set and depth of knowledge were truly impressive and exactly what we needed, particularly as we chose to stay closely involved in the renovation rather than hiring a larger construction and project management company. We genuinely don’t feel we could have made a better choice. It’s not always easy to find a builder who is reliable, honest, and trustworthy, so I feel very fortunate to have worked with Michael. I would recommend him without hesitation and will absolutely continue to work with him on future projects, big or small.
Prodec Construction ltd
Rating: 5 out of 5
Extension Builder in Westminster
With over 16 years experience our reputation has developed very soundly as a specialist building contractor. We work on many types of projects including domestic houses, health care sector, and housing developers. Our service is designed around delivering the highest standard and quality.
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Latest review:
Painting & Decorating- 18 Jun 2025
Martin has done an excellent job for us. He is professional, polite and helpful.
Be-Studio Ltd
Rating: 5 out of 5
Extension Builder in Westminster
bé-studio is an award-winning interior design practice specializing in contemporary residential and commercial projects. We collaborate with a broad range of professionals to bring diverse projects to life, no matter the size, no matter the scope. Services Provided Architectural Design,Home Renovation, Interior Design, House Extension, Kitchen Design, Garden Design, Living Room Design, Home Extensions, House Plans, Complete Bathroom Renovation, Design & Build
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Latest review:
Bilal and his team designed the plans for the extension of the ground floor of our house. He invested time in understanding our ideas and needs, and translated them into something that is both inspiring and practical. They provided amazing visualizations for us to imagine the final look.I recommend Bilal and his colleagues for a hassle free and highly professional service.
Good Choice Builders LTD
Rating: 5 out of 5
Extension Builder in Westminster
We are the building company that specialized in Loft Conversions, Extensions and Refurbishments. By this moment we worked as a subcontractors, now we have all neccessary and feel free to participate to the tenders, prepare the informative and detailed contracts and estimations, management.
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Latest review:
Extensions- 8 Jul 2019
A very efficient builder who did the plans which where passed first time when we needed help he found someone to help very clean and tidy and on time
HOLCMAN CONSTRUCTION LIMITED
Rating: 5 out of 5
Extension Builder in Westminster
Established in 1998, Holcman Construction Ltd has emerged as a premier construction and renovation company in Marylebone, London. ‍ Specialising in high-end residential and commercial projects, we pride ourselves on our collaborative approach, partnering with homeowners, renowned designers, and top architects across the UK. Our dedicated team, a family of construction experts, is committed to delivering excellence in every project. We hold ourselves to the highest standards, ensuring each build not only meets but exceeds client expectations. Discover our diverse portfolio, showcasing our exceptional craftsmanship in London's dynamic property market. Let Holcman Construction elevate your next London-based construction or renovation project to new heights of sophistication and quality
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Latest review:
We hired Holcman Construction ltd to build out our new loft as well as extension on our 2500 sq feet property in West Hampstead, London. We are very pleased with their work ethic and professionalism. The work was completed ahead of schedule and we can not praise them enough. Thank you

4.1

Top rated Extension Builders

Our Extension Builders in Westminster, are rated 4.1 out of 5 based on 18 reviews from customers like you.

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Easily find verified local tradespeople. Just post your job to get quotes from tradespeople near you across the UK.

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

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 Westminster 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 Westminster who are available and interested can respond to your post.

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

What are the hourly rates of extension builders in Westminster?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Westminster 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 Westminster extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Westminster home extension project is likely to cost.

Find extension builders in Westminster with MyBuilder

Hiring the right extension builder in Westminster 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 Westminster extension builders. Once your job is live, we’ll share it with home extension builders in Westminster who can express their interest.

Step 2: Compare different extension builders in Westminster

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

Step 3: Hire Westminster extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Westminster, 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.

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

What to ask a Westminster extension builder before hiring?

Before hiring an extension builder in Westminster or extension building company in Westminster, 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 Westminster?

An extension builder in Westminster 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 Westminster 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 Westminster?

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 Westminster 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 Westminster 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 Westminster

Can an extension builder in Westminster help with planning permission?

Yes, many extension builders in Westminster 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 Westminster handle everything from design to construction?

Many Westminster 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 Westminster help with materials and finishes?

Yes, most extension builders in Westminster 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.