Extension builders in Westminster

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.6 (20 reviews)

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Some of our top rated extension builders in Westminster

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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
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
Krots
Rating: 5 out of 5
Extension Builder in Westminster
Wood carpenter for doors, external rooms, ceilings, stairs, bedrooms, kitchens, railings and gardens
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Latest review:
Carpentry- 28 Sep 2025
Great handywork,
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.
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
Tawfik Werfalli
Rating: 5 out of 5
Extension Builder in Westminster
At Miko Construction, we specialise in high-quality residential refurbishments, extensions, and fit-outs. We’re a small, experienced team that takes pride in delivering well-crafted work with clear communication throughout. Whether it’s a full home renovation or a bespoke interior project, we bring a personal, hands-on approach from start to finish.
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Latest review:
Tawfik’s team was very professional and very knowledgeable, they done a great work including helping me with the design and understanding the process required to complete a project at this size, he completed the electrical work tested it and also included great ideas with the LED lights that made A beautiful design at the end, he also recommended a lot of subcontractors in the area are very competitive in their price and practically manage the project with me from inception to completion.
Soho Building and maintenance Ltd
Rating: 5 out of 5
Extension Builder in Westminster
We are Soho Building and Maintenance Ltd, currently in our second year of business. We have an abundance of experience in the building industry with our own fully vetted trades including our own in house quantity surveyor for any large tenders. We undertake works of any amount no matter big or small, we can work with architects under minor works contracts
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Latest review:
Rear single story extension. Knocked wall out to extend kitchen. Craig -workman - very good. Lee and Dan project managed and were both excellent. Very please with everything, they turned up on time and when they said they would, cleaned up and finished build on time as agreed. I would recommend them to anyone.
Gjon
Rating: 4 out of 5
Extension Builder in Westminster
I have been in the construction industry for over 25years Pimlico 📍
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Latest review:
Tiling- 24 Mar 2022
Gjon and his son Julian did an amazing job tiling our kitchen floor. They were prompt in communications and completed the job within the agreed time. Left the job clean and tidy after themselves. Will probably hire them again to install a splashback later on in the project.
Sdl Services Ltd
Rating: 5 out of 5
Extension Builder in Westminster
SDL Services, we are experts in all aspects of construction and offer various solutions tailored to your specifications, from refurbishments, extensions, and loft conversions to groundwork. Our team is experienced in handling the delicate details and customization that help bring your project to life. Whether upgrading your environment or starting from scratch, SDL Services prides itself on delivering results beyond the norm.
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Latest review:
Landscaping- 15 Jul 2026
Zen and his team did an excellent job transforming my garden. They removed the old decking and arch, installed a new porcelain patio, painted the fences and walls, laid new turf and completed the work to a high standard. The finished result looks fantastic and I’m very pleased with it.
VORTEX SERVICES LTD
Rating: 5 out of 5
Extension Builder in Westminster
Vortex Trading Corporation Ltd, with over 25+ years staff and associates experience behind can offer our clients the best value for money in the property refurbishing fields. Our staff and associates having background with the Institute of the Federation of Master Builders, LABC (Local Administration Building Control), CSCS (Black Card), Party Wall Surveying, NTC-7 Qualifications, Masters in Project Management, and Qualified Architectural Designer and QS/Estimators. Offering turnkey project to clients.
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Latest review:
I had an extension built. The job was of a high calibre and professional standard and went to plan. Ross is well-organised, highly knowledgeable about building and construction, creative, dexterous, industrious, talented and has excellent problem-solving skills. He works professionally and is highly reliable. I strongly recommend Ross of Vortex Services Ltd to whoever is seeking building work done to his or her property.
AK Electrical Services
Rating: 5 out of 5
Extension Builder in Westminster
AK Electrical services is part of Crest Construction & Interiors Ltd. We carry out full building works from foundation to the roof. We are specialised in basement and underpinning works. Our trade people are fully qualified and we work to the highest standard. We have many years experience in domestic electrical and commercial installation. We provide electrical services for all domestic/ commercial projects. We are registered in ELECSA PART P SCHEME, 17th edition. All works are guaranteed.
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Latest review:
Fully electrify a new rear, 2 storey side, porch extension and shed. Arek was always the first one on site, worked very professionally, interacted well with the other builders and was happy to accommodate minor changes to the project. He suggested improvements to the the lighting layout and configuration were taken aboard. I highly recommend him and I'll also be using him to change my house consumer unit in the coming weeks.
Prestige Building Design Ltd
Rating: 5 out of 5
Extension Builder in Westminster
My name is Warren & has been in the building industry for over 35yrs Began as a carpenter and has developed & moved into all area and aspect of the building industry covering from the least to the greatest, Prestige Building Design Ltd. Are a team of Multi-Skill tradesman, Crafts man & builders which will converts your ideas into reality. Our portfolio covers New build,Extension,Loft Conversions,Renovations,Bathrooms,Kitchens, We pride our self on our ability to deliver & Customer satisfaction
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Latest review:
Extensions- 24 Apr 2023
Warren and his team have been with us for over a year now, first building our extension and then retained for additional work around the house. The quality of work is high, the pricing is very competitive and the team are a pleasure to have around. I am pleased we hired Warren and do not hesitate to recommend him.
KG BUILD
Rating: 5 out of 5
Extension Builder in Westminster
With your specifications and our expertise, we happily take on any building work and produce excellent results. Extensions, Loft conversions, kitchens, bathrooms, garden rooms/studios/outbuildings, roofing, flooring, carpentry and joinery etc
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Latest review:
Carpentry- 13 Dec 2025
Kwame did a great job and was thoughtful, communicative and very skilled with the work he was carrying out on our joists. I would recommend KG build to anyone looking for a good price and a high standard of work.
Araron construction London Ltd
Rating: 4.7 out of 5
Extension Builder in Westminster
Aaron Construction London Ltd is an established building and construction company with 25 years of experience delivering high-quality building, renovation and property maintenance projects across London. We are fully insured and VAT registered, providing our customers with a professional, reliable and trustworthy service from the initial quotation through to completion. Our experienced team can assist with projects of all sizes, from smaller repairs and maintenance works to complete renovations and major building projects. We take pride in delivering high standards of workmanship, attention to detail and excellent customer service. Our Services Include: * General building and property renovations * Roofing, flat roofing and roof repairs * Leadwork, slating and tiling * Gutters, fascias and downpipes * Brickwork, repointing and structural repairs * Damp, mould and water-damage repairs * Bathrooms and kitchens * Plastering, rendering and decorating * Doors and windows * Drainage and external works * Extensions and refurbishment projects * Property maintenance and repairs We believe in clear communication, honest quotations and dependable workmanship.
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Latest review:
Handyman- 17 Oct 2026
Aaron was amazing. He gave options and prices. He put up my broken curtain track really quickly. Very professional, kind and considerate. Highly recommended. Very happy customer. Thank you Aaron
CJ Carpentry
Rating: 5 out of 5
Extension Builder in Westminster
We are joiners by trade, passionate on what we do over the years. We have combined over 32 years of experience on carpentry/joinery itself. As there is always demand, we started delivering any type of construction work, full house refurbishment, kitchens, bathrooms etc. Always preserving our high quality of work, honesty, professionalism. Fully committed to anything we can come across, always find clients, architects solutions so we can achieve everyone’s dream, expectations.
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Latest review:
Carpentry- 18 May 2022
Very professional and friendly tradesman. Work was carried out perfectly and I couldn't recommend him high enough. Brilliant work ethic and he went the extra mile to carry out the works impeccably. Privellage to work with him.
N&G Projects Limited
Rating: 5 out of 5
Extension Builder in Westminster
We are a family business with over 70 years of experience in all building and renovations. We are happy to look at any work large or small. All works are fully insured.
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Latest review:
Carpentry- 19 Mar 2025
Guy and his team were very professional. I recommend them and would use them again

4.6

Top rated Extension Builders

Our Extension Builders in Westminster, are rated 4.6 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 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.