Extension Builders in Westminster

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.2 (19 reviews)

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Some of our top rated extension builders in Westminster

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SIM Building Services Ltd
Rating: 5 out of 5
Extension Builder in Westminster
SIM Building Services Ltd is a construction company providing services in Croydon/London and surrounding areas. Our team has over 20 years of combined experience in residential, commercial and interior/exterior construction across all trades. We’re dedicated to a high level of customer service and will take the time to make sure that you are comfortable with the services we are providing.
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Latest review:
Extensions- 18 Sep 2022
Dritan is genuine and a man who keeps to his word. Very happy with him and his team. 100% recommend to others.
Vertex Projects
Rating: 5 out of 5
Extension Builder in Westminster
Vertex Projects is a professional and trusted construction partner dedicated to bringing your vision to life. We specialise in a comprehensive range of services, including painting and decorating, building extensions, expert demolition, and plastering. Our expertise also extends to new fencing and the custom construction of bespoke balconies. At Vertex Projects, we pride ourselves on being a respectful team that treats every home and site with care, ensuring high-quality craftsmanship and a seamless experience from start to finish.
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Latest review:
Hard Flooring- 7 Jul 2026
Straight forward process with no hiden costs. The work was completed to a good quality with the new flooring in the garden outhouse and the waste removed. Will hire again in the future.
kurt contractors ltd
No reviews yet
Extension Builder in Westminster
Hi, I’m a local contractor and I take a lot of pride in doing things properly. Whether it’s a full refurb or just a small repair, I treat every job like I’m working on my own home. I know having work done can be stressful, so I try to keep everything simple and straightforward—turn up when I say I will, explain things clearly, and make sure you’re happy with the result. If you’ve got something in mind, feel free to get in touch and we can have a chat I'm always happy to help and see what we can do.
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Alex
Rating: 5 out of 5
Extension Builder in Westminster
Hi I offer good quality work which includes general construction works, painting interior, exterior, walls and ceiling repair and wood work I also offer handy man jobs, decking installation and repair,groundwork jobs.
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Latest review:
Painting & Decorating- 6 Jul 2026
Excellent communication and decorating done to a high standard. The rooms look beautiful and Alex was very clear about what needed to be done at all stages. When bits of the job changed, he revised the bill down in keeping with the fact less work was needed.
Heg Construction ltd
Rating: 5 out of 5
Extension Builder in Westminster
Hello I am Edmond, the proud owner of HEG Construction Ltd, A little about us With many happy and returning customers over the last 15 years, you can be sure of being well looked after. Our aim is to provide a stress free project, delivered in a manner that I am confident will exceed your expectations. I work with a small team of trusted colleagues, who communicate and work together well. Our customers are accustomed the outstanding quality of projects we complete, by sourcing quality materials with experienced installers we create truly bespoke masterpieces lasting our customers many years. Up to 5 year guarantees are included as standard on all completed work. Thank you for taking the time to consider our company’s profile, I look forward to hearing from you. HEG Construction Ltd
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Latest review:
Edmond did stellar work on the full kitchen renovation of our central London flat, and I can't recommend him highly enough. His professionalism, expertise, and attention to detail are on another level, and he is an excellent communicator. The end result was meticulous; he worked efficiently within the agreed timelines while resolving unexpected challenges and providing solid guidance throughout the project. Edmond also has a strong network of professionals who were just as reliable and easy to work with as he is. We also appreciated how tidy our home was left every day and how well all areas were protected during the build.
JBS Jonay Building Services Ltd
Rating: 5 out of 5
Extension Builder in Westminster
Jonay Building Services LTD has been a consistent and trustworthy Construction Company in North London since 2004.We operate all over London and surrounding areas. J.B.S undertakes a great range of works for a huge variety of clients; From residential extensions, loft conversions and renovations, to commercial landscaping and shop fitting. Whatever your project we have a solution for you.
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Latest review:
Restoration & Refurbishment- 13 Jun 2023
This company was very professional. The work was completed on time and to a high standard. The work was also, good value for money. I would recommend JBS services to anyone seeking either home or business general refurbishment and building works.
alpha green construction
Rating: 5 out of 5
Extension Builder in Westminster
I have 25 years experience in the trade.specialise in innovation and reliability. Trade built company generally around masonry , roofing and all other structural undertakings. We specialise in loft conversions and house extensions , masonry and landscape gardening. We also provide design and build schemes for the above topics.
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Latest review:
Extensions- 14 May 2019
We love Berry, he has followed our project from the beginning to the end and he has been there all the steps of the way. He listened to our ideas and enriched them with more of his adding his special attention to details skills. For every problem, we had along the way he talked to us making sure we were happy with alternative solutions. Plus he is able to create a friendly working environment which makes the invasion of your house less intrusive, he has been very respectful of our space. We can genuinely say that he has gone beyond our expectations, and will be very happy to do future works with him. Luca and Nick
Geometric Renovation Ltd
Rating: 5 out of 5
Extension Builder in Westminster
Geometric Renovation is a London based renovation and construction company specializing in high quality renovations, maintenance and remodelling services with affordable price and highest standards. We also cover the Greater London area.
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Latest review:
Painting & Decorating- 6 Aug 2022
Good Job, friendly and helpful
A2Z
Rating: 4.7 out of 5
Extension Builder in Westminster
A2Z, UK-wide builders and problem solvers. Renovations, refurbishments, rebranding, maintenance. Fully insured, highly communicative team for home and commercial projects. We started A2Z because we were tired of the runaround. Missed calls, vague quotes, jobs that dragged on. We knew there was a better way to run a building company so here we are trying to make a change.
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Latest review:
Plastering- 25 Jul 2023
Great team ,very professional and work very hard. Great team to pull of any major poject.they tiled and plaster for me.cant fault their work amazing.
Singh Delivers Ltd
Rating: 5 out of 5
Extension Builder in Westminster
I love to install carpets. Carpet isn’t just a floor but a lifestyle. I specialise in carpet fitting and maintenance. I tend to provide quality work for clients through years of experience. Every job requires a coordination between client and company, and this is how I work by coordinating with client because end of the day client would be looking at work and shouldn’t have any second thoughts.
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Latest review:
Painting & Decorating- 23 Feb 2026
Good job, delivered fast at a good price. Many thanks!
Ajila Limited
Rating: 4.5 out of 5
Extension Builder in Westminster
Ajila Limited is a professional construction company specializing in house refurbishment. With a commitment to quality craftsmanship and attention to detail, we transform homes to meet the highest standards of functionality and style. Whether it's a full renovation or specific improvements, our experienced team delivers exceptional results that enhance both the beauty and value of your property. The company engages in multiple trades which includes plumbing, kitchen, bathroom, tiling, extension, home refurbishment etc
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Latest review:
Plumbing- 2 Apr 2025
Great service and good price. Thank you
Pine Construction Ltd.
Rating: 5 out of 5
Extension Builder in Westminster
As a civil engineer and principal building contractor we consult, design, construct and project manage any dwelling and commercial projects from minor repairs to complete new-build as well as any type of restoration/renovation and basement construction projects.
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Latest review:
Extensions- 19 Oct 2017
The best team in London to work with they are highly skilled professionals and very easy to work with looking forward to work with them again
Vullcan Construction
Rating: 1 out of 5
Extension Builder in Westminster
We are a CHAS and Safe Contractor accredited organisation specialising in the provision of bespoke and high end specifications in relation to all aspects of internal refurbishments for both contemporary and period properties, in addition to commercial fit-out works, as well as small to large scale structural alternations. Our clients choose us for our experience and strong level of communication during our projects, our highly competitive rates and the high level of quality of our finish.
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Latest review:
Extensions- 25 Aug 2020
I did my due diligence on Vullcan, but things went downhill. After a week i got a pre-tax invoice for £3000 for a more "complex" drainage system which was already completed, this was the start of them trying to get around contract items and look for every way possible to charge extra fees which i can’t go through in the word limit here. When that dint work they refused to do the work. e.g. they literally installed a tempered glass sheet, with liquid glue on my roof and stated to me that this was a "roof window". I had to show them buildings regulations that this was unacceptable and illegal especially when our contract said it has to be a VELUX ROOF WINDOW! Promised a 6-8 week completion, this is 9 months later. I had now paid about 90% of the original bill and 100% of additional costs. The final payment was due after completion and a 2 week snagging period. But the demand for payments started, with threats to sue. This was laughable as they hadn't completed the job. •The roof was leaking •Electrical issues with the fuse box and multiple light /electrical points •Outstanding items •The buildings controls company stated they would not be able to sign off on the building work because of outstanding issues, which I wouldn’t have even known as they lied stating they HAD the certificate. I agreed to send a FULL payment to an escrow company and pay HALF of the costs so they can complete and fix safety issues but they refused! Shameful experience.
Denis Osan
No reviews yet
Extension Builder in Westminster
I am a self-motivated individual with a strong aptitude for initiative and problem solving, consistently delivering results with meticulous accuracy and thoroughness. I leverage strong time management and skills to balance multiple priorities.
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Pro Construction London Ltd
No reviews yet
Extension Builder in Westminster
Pro Construction London is a trusted London-based building company with over two decades of experience delivering high-quality renovations, refurbishments, and property maintenance. We pride ourselves on our professionalism, reliability, and attention to detail, ensuring every project is completed to the highest standard. From full property renovations and loft conversions to bespoke finishes and one-off repairs, we provide a seamless service from start to finish — clear communication, transparent pricing, and a tidy worksite every time. Our reputation is built on satisfied clients who return to us for future projects, knowing they can rely on a skilled and dedicated team to bring their ideas to life.
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JK Building Services
Rating: 5 out of 5
Extension Builder in Westminster
JK Building Services estabileshed in 1998,has build a solid reputation for providing quality work at affordable prices. We are specialist in house extensions,,renovations, full refurbishments, brickwork specialists ,all general building work, structure works like construction of roofs, dormers , opening load bearing walls interior and exterior and installing steels . Also we offer welding services to our lovely clients from welding big steels on site to small household items too:)) *review* Lindsey : Jacek was brilliant. He is very professional, friendly, knowledgeable, tidy and made great recommendations. Jacek is talented in a lot of areas. Very refreshing to work with someone like him. We've already hired him again for bigger jobs. Highly recommend him.
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Latest review:
Conversions - General- 22 Jun 2026
Fantastic job. Lovely guy. Would definately use him again!

4.2

Top rated Extension Builders

Our Extension Builders in Westminster, are rated 4.2 out of 5 based on 19 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.