Extension Builders in St James

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 St James

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Maxmar Construction Ltd
Rating: 4.7 out of 5
Extension Builder in St James
We are a company that pride ourselves on taking excellent care of the ‘whole project’, from design to completion. We can, on your behalf, manage your project, coordinating all the required trades to turn up as and when required, leaving you to get on with daily life. Your dream home could be closer than you think, allow us to turn your ideas into reality. My company has lots of experience working on many different projects, big or small! On a personal level I am a honest hardworking individual. I have a lot of experience in all aspects of building work. I am familiar with building regulations and used to dealing with building control officers from the various local authorities. I have a fully skilled team of builders who cover all types of general building maintenance including kitchen and bathroom fitters, plasterers, flooring specialists, painters and decorators. The company offers a fully insured and guaranteed comprehensive
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Latest review:
Conversions - General- 21 Jul 2013
Flooring & lighting to extension not completed appropriately and resulted in later problems.
Stn Contacts Ltd
Rating: 5 out of 5
Extension Builder in St James
Should you require a quotation for any works, or even just advice, please call /e-mail us and we will be happy to help you: Basements Extensions Loft conversions New builds Refurbishments Kitchens and bathrooms Carpentry and joinery Roofing Insurance work Design and build
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Latest review:
Stan and his workers are very reliable, professional with there workmanship and very good value for money. Compared with other quotes I received. I had a ground floor and 1st floor extension and a new large kitchen installed and a large bedroom ensuite on the 1st floor.
DUMITRU HUJA
Rating: 5 out of 5
Extension Builder in St James
Extensions loft conversation ,refurbishment,bathroom fitting,kitchen fitting,electrical and plumbing
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Latest review:
Kitchen Fitting- 17 Nov 2025
We recently had our kitchen refurbished by Dumitru, and we couldn’t be happier with how everything turned out. He’s one of those rare builders who combines professionalism with real care for the details. He worked efficiently, kept the place tidy throughout the project, and always cleaned up after himself — which honestly made such a difference when living through a renovation. What I appreciated most was how supportive he was when it came to choosing the right materials. He guided us through the options without ever pushing, and his advice proved spot-on. The final result is exactly what we hoped for and more. If you’re looking for someone reliable, skilled, and easy to work with, I totally recommend Dumitru P.S. For anyone curious about the scope of the work: Dumitru changed our worktop, removed the old tiles and redid the flooring with laminate, installed a new cooker and hob, fitted a new sink, repaired the walls after the new boiler went in, and repainted everything. Top work
THE WEST 1 SERVICE GROUP LTD
No reviews yet
Extension Builder in St James
West-1 Service Group is a London-based contractor providing reliable building maintenance, refurbishment and property repair services. We support homeowners, landlords, property managers and commercial clients with a range of works including building fabric repairs, refurbishment projects, fire door compliance, waste clearance and general property maintenance. Our focus is simple – clear communication, reliable service and work carried out to a high standard. We take pride in delivering practical solutions and maintaining safe, well-kept properties. Whether it’s a small repair, planned maintenance or a larger refurbishment project, we approach every job with professionalism and attention to detail. We are always happy to discuss new projects and provide straightforward advice where needed.
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AJ REFURB SPECIALIST LTD
Rating: 5 out of 5
Extension Builder in St James
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 😊
KG DESIGN & BUILD LTD
Rating: 5 out of 5
Extension Builder in St James
Hi I`m Kleida .I worked in Building industry for a while now and I have built a quite a knowledge on extensions loft conversion and refurbishment . I recently decided to start working for myself .I also have a very good working team with various knowledge on various stages of projects .
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Latest review:
Conversions - General- 8 Oct 2025
Gaz and his team were professional and hard working, and clear about what would happen when. The job is now finished to a good standard, and on time.
A-level building services
Rating: 5 out of 5
Extension Builder in St James
Welcome, thank you for looking at my listing. We have been helping customers for more than 15 years to convert their houses into homes. It is understanding how difficult it can be sometimes to make the right decision-so let us help you. Get in touch for a chat and arrange a free quote.
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Latest review:
Bathroom Fitting- 7 Nov 2024
Wouldn’t hesitate to work with Alex again, or recommend to others. Good communication, with all trades (plastering, tiling, electrics, plumbing etc.) completed to a high standard. Reliable and always on time. Reasonably priced.
ScutariConstruction
Rating: 5 out of 5
Extension Builder in St James
Scutari Construction is a limited company based in London. We are a very reliable and professional team of tradesmen with over 10 years of experience on the building industry, committed to deliver the highest levels of quality and service to our clients.
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Latest review:
Extensions- 14 Apr 2021
Mel and team completely transformed our house in a very timely and professional manner. I honestly cannot say enough good things about him. The team works really hard and their model provides the fastest, highest quality construction at a reasonable price. Use these guys!
Maclondonbuilding
Rating: 4.9 out of 5
Extension Builder in St James
MACLONDONBUILDING specialist in general construction and renovation services. All kind of house conversions . Our works are performed at the highest standard with attention to the details. Professional team always happy and enjoyed of the work.
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Latest review:
Tiling- 16 Jan 2026
Mac was fantastic and went above and beyond to do the job to a high standard, working well into the evening to get it done. I’d recommend him without hesitation for any work you need doing - big or small. We’re delighted with the finished product.
4 You Residential Limited
Rating: 5 out of 5
Extension Builder in St James
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.
Guardian Angels Property Ltd.
No reviews yet
Extension Builder in St James
Property development company. All types of brickwork and blockwork. Painting and decorating. Refurb and renovations. No job too big. Diligent, honest & hardworking.
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RT Build
Rating: 5 out of 5
Extension Builder in St James
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.
Zsolt
Rating: 4.7 out of 5
Extension Builder in St James
It is a family business with 20 years of experience. We have a wealth of experience in all areas of building construction, expansion and renovation.We rarely hire more than one client, so we can allow us to complete the project from start to finish in the right quality, in the right time fame. Traders are fully trained, respected and trusted. Contact us if you want your Dream Home to become a reality.
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Latest review:
Bathroom Fitting- 22 Sep 2025
I recently had my bathroom completely renovated by Zsolt and Mario and the experience was outstanding from start to finish. They were professional, punctual, and incredibly skilled—nothing was too much trouble, and their attention to detail was second to none. One of the highlights of the project was the walk-in shower they installed, It’s beautifully tiled, and gives the bathroom a sleek, modern feel. They kept the workspace clean, communicated clearly throughout. Zsolt clearly take pride in their work, and it shows in the final result. The bathroom looks fantastic and feels like a real upgrade to the home. I wouldn’t hesitate to recommend them to anyone looking for trustworthy, high-quality builders. Thanks again, Zsolt and the rest of the team, you’ve done a brilliant job.
Volodymyr Girkovskyi
Rating: 4.7 out of 5
Extension Builder in St James
I am responsible, I do my job carefully, I have extensive experience in building and renovating houses.
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Latest review:
Handyman- 9 Oct 2025
Good job, done as agreed
Jozeph
Rating: 5 out of 5
Extension Builder in St James
I am a professional and reliable tradesman who works to very high standards, these standards have helped me to build up an excellent reputation with regards to all work that I have carried out. Please request a quote through mybuilder.com for a free and honest estimate
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Latest review:
Handyman- 3 Oct 2015
Fast, efficient, friendly builder. Very skilful, quality work at a reasonable price. Couldn't be happier. Fully recommend Jozeph. Emma & Emanuel
Fastway Constructions Limited
Rating: 5 out of 5
Extension Builder in St James
At Fastway Constructions, we are dedicated to redefining the construction industry through sustainable practices and innovative solutions. Based in the United Kingdom, we pride ourselves on delivering exceptional quality and reliability across four key sectors: Residential Constructions, Commercial Constructions, Industrial Constructions, and Renovation & Remodelling Here at Fastway all of our employees are fully qualified, skilled and very experienced building contractors that have worked on hundreds of projects over the years resulting in 100% client satisfaction, full job completion on time, and always well within budget. All employees hold cscs cards for their relevant trades along with health and safety certificates and first aid for a competent safe worksite at all times. We are a building contractor with a professional approach to all our projects. We offer a seamless and multi-trade service, for all domestic projects from new builds, extensions, loft conversion, renovation to fully finished houses, all tailored to meet our clients’ specific requirements.
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Latest review:
Plumbing- 1 Aug 2025
Jitin did a good job in finding a solution to the leak in the washing machine drainage pipe. He used his experience in problem solving and fixed the issue. Thanks Jitin

4.2

Top rated Extension Builders

Our Extension Builders in St James, 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 St James?

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 St James 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 St James who are available and interested can respond to your post.

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

What are the hourly rates of extension builders in St James?

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

Find extension builders in St James with MyBuilder

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

Step 2: Compare different extension builders in St James

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

Step 3: Hire St James extension builders with confidence

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

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

What to ask a St James extension builder before hiring?

Before hiring an extension builder in St James or extension building company in St James, 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 St James?

An extension builder in St James 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 St James 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 St James?

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 St James 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 St James 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 St James

Can an extension builder in St James help with planning permission?

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

Many St James 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 St James help with materials and finishes?

Yes, most extension builders in St James 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.