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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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
FLYNN properties
Rating: 5 out of 5
Extension Builder in St James
With over 10 years experience and always producing high quality finishes. From kitchens, bathroom to extensions and always with a good positive happy attitude. let us work with you to design and achieve exactly what you’re looking for.
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Latest review:
Tiling- 7 Aug 2023
Paul was great. Easy regular comms. Arrived early on the day and fit me in as best he could. Straight to it, great work, very professional and sorted out some other problems as they were discovered. Talked me through options and did what was asked to a very high finish. Would highly recommend and use again.
Graal Structural Engineering Ltd
Rating: 5 out of 5
Extension Builder in St James
We offer Structural Desing and Calculations for New Build, Extensions, Loft Conversions, etc. Detailed drawings and calculations for Building Control. We offer one-stop-shop services including, planning applications, architectural & structural design, cost estimations, project management and construction works.
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Fox-Hound London Developments LTD
No reviews yet
Extension Builder in St James
At FOX-HOUND LONDON Developments, we specialize in redefining luxury living through meticulous craftsmanship and innovative design. Based in Central London, we are committed to creating exceptional spaces that reflect elegance, quality, and enduring value. From bespoke refurbishments to transformative developments, our expertise ensures every project is completed to the highest standards, leaving a lasting impression of excellence. Our team works hand-in-hand with leading architects, designers, and highly skilled tradesmen to ensure that every detail exceeds expectations. Whether it’s a timeless renovation, a contemporary extension, or a complete transformation, we pride ourselves on delivering results that reflect your individuality while enhancing the value and essence of your home.
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Best Quality Double Glazing Ltd
Rating: 4.8 out of 5
Extension Builder in St James
Aluminium and UPVC manufacturers/ Suppliers and Fitters Single Doors / Double doors / French Doors / Bifold Doors / Conservatories / Roof Lanterns / Composite Doors All kind of Quality Windows and Doors at trade prices. We also deal with traders. Unbeatable prices with quality products
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Latest review:
Windows & Doors (uPVC & Metal)- 13 Jun 2024
Job done promptly and within the budget required. The window was put in place so quickly I didn’t have a chance to wipe the dust of it before it went in! Would suggest the fitter carries a cloth with him to wipe fingerprints and bits off the window before installation but really a small thing considering. Overall very happy with the job done. Thanks.
South London Rooms Ltd
Rating: 4.5 out of 5
Extension Builder in St James
We run a team of home Improvement professionals. We carry out all types of home improvement services. We specialise in Loft Conversion and Extentions. We are based in South London area. We aim to provide the best quality work for our customers.
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Latest review:
Extensions- 22 Dec 2022
Imran is a contractor who is personable and is trying hard, but at the end relies on different teams of builders to carry out the work. His knowledge of building work appears at time limited. In our case, this has often led to poor communication/hand-over, extensive delays and often poor (if not careless) craftsmanship. Very stressful. We now have builders (family business) finalising our project.
Agnuss Construction Ltd
Rating: 5 out of 5
Extension Builder in St James
We are a construction company that operates in the local area mostly, but we can also cover all the other areas of Greater London. Our Services include Extensions, Loft Conversions, Refurbishments, and basically all the aspects of building work. We specialise in residential and business projects.
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Latest review:
Agnuss Construction carried out and completed our house renovation, kitchen extension and loft extension successfully. Elio and his father, Mario were very communicative throughout and very reliable. The works were carried out on time and on budget. I would be happy to recommend Agnuss Construction and use them again in the future.
Nenad Jevtic
Rating: 5 out of 5
Extension Builder in St James
I've start working in the building industry 15 years ago. Over the years working in the industry I have moved up the lader and for last 4 years worked as project manager for different building company's . I have vast experience in designing and working on projects to highest standards to meet deadlines and within the budget . I have team of highly experienced tradesman and we always go extra mile to meet customers needs.
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Latest review:
Conversions - General- 6 Feb 2019
Nanad and his team have been wonderful from day one. We have had them with us a number of weeks doing all the jobs they quoted for and more, they are fast efficient and courteous of the fact we lived in for a lot of the work. Everything has been finished to a great standard and we are thrilled with our house which has been completely transformed. We have already recommended them to friends and will continue to do so and hopefully have them back in future. They are creative, solve issues that crop up easily and without fanfare extremely hardworking and all round an excellent team! Thank you for everything! Emma and James
Elgon Construction Limited
Rating: 5 out of 5
Extension Builder in St James
Be assured that your home is in good hands. We have provided building services for 18 years in London. The advantages of the company are a high quality of service and punctuality.
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Latest review:
Painting & Decorating- 17 Nov 2023
From connecting with Elgon to having the job done it was a smooth process. Elgon was professional friendly and put me at ease straight away. Will definitely use them again in future.
BRH
Rating: 5 out of 5
Extension Builder in St James
We are a professional home repair and maintenance company dedicated to providing high-quality services to homeowners and property managers. With a skilled team of technicians and years of experience, we specialize in a wide range of home improvement solutions, including plumbing, electrical work, carpentry, painting, drywall repair, and general handyman services. Our mission is to deliver reliable, efficient, and affordable repairs that help maintain the safety, functionality, and beauty of your home. Whether it’s a small fix or a major renovation, we are committed to getting the job done right the first time. Customer satisfaction is at the heart of everything we do, and we strive to build long-lasting relationships through trust, professionalism, and excellent service. Not : no advance payment
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Latest review:
Handyman- 17 Feb 2025
Very good job. Came quickly and did it well
Wall Done SP
Rating: 5 out of 5
Extension Builder in St James
We believe your home should evolve with your lifestyle. Whether you're expanding your living space with a loft extension or completely renovating your property, we turn your ideas into reality.
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rr.construction
Rating: 5 out of 5
Extension Builder in St James
Working with: simfonia kitchens,howdens kitchens,ikea kitchens,wren,benchmarx,magnet,b&q kitchens,selco,wickes homebase.8 year experience of building in uk
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Latest review:
Hard Flooring- 8 May 2019
I was very pleased with Igor’s work on the flooring and under floor heating, so decided to ask Raimundas to quote for a large bathroom, hallway, fitted kitchen, rewiring of all electrics and flooring throughout the rest of the flat. Due to work and my partner living overseas, I needed to trust somebody for a long length of time with my keys and my property. I was able to have a lot of the work done while not in the country, communicating with pictures, videos etc. Obviously this was important for me and made having the work done easier. There were also many problems with the kitchen delivery and other things that didn’t go according to plan. Raimundas was patient and polite at all times, even though it was sometimes rather frustrating. I highly recommend his services, and would definitely consider RR Construction for the next job
Home Renovation City Ltd
Rating: 5 out of 5
Extension Builder in St James
SKILLS 1 .Plastering 2. Lay Bricks 3. Tiles 4.Renderin 5. Painting decoration 6. Coving 7. Dry Lining 8.Flat Ceilings 9.Renderin 10 Extensions Hello, I am Eneo, proud owner of Home Renovation City Ltd and here’s a little about me: With many happy and returning customers over the last 10 years, you can be sure of being well looked after. My aim is to provide a stress free project, delivered in a manner that I am confident will exceed your expectations. I carry out all work myself and will be your single point of contact. My customers are accustomed with the outstanding quality of my projects, by sourcing quality materials with experienced craftsmanship I create truly bespoke masterpieces lasting my customers many years. Year guarantees are included as standard on all completed work.
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Latest review:
Painting & Decorating- 23 Jul 2022
Eneo painted One bedroom flat in a highly professional manner in a very tight schedule. He was very tidy and provided High quality service. Highly recommended
Petrit Gjoni
Rating: 5 out of 5
Extension Builder in St James
Welcome to my profile, My Company is Gjoni Contractors LTD and my name is Petrit, a hard working men with 10 years experience in landscaping, decking, fencing, extension, loft conversion, partition, plasterboard, plastering, painting decoration, tiling, laminating, plumbing and electrical. My company is Gjoni Construction and consists of 10 employees . I provide quality service to my customers and make sure we have satisfying results. BUILD YOUR DREAM HOUSE TOGETHER !
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Latest review:
Landscaping- 10 Jan 2026
Fantastic workmanship and finish will use again
Builder
Rating: 5 out of 5
Extension Builder in St James
Welcome to our versatile construction services. We specialize in: Bricklaying: Crafting sturdy and appealing structures. Blocklaying: Building strong foundations for your projects. Garden & Retaining Walls: Enhancing your outdoor spaces. Porches: Creating inviting entryways. Extensions: Expanding living spaces seamlessly. Landscaping: Designing captivating outdoor environments. With attention to detail and commitment to excellence, we're here to turn visions into reality.
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Latest review:
Blerim undertook the task of constructing a rear extension to my home, which involved creating additional living space while seamlessly integrating it with the existing structure. The project was quite intricate, requiring meticulous attention to detail and a deep understanding of construction techniques. Blerim's craftsmanship was truly remarkable. He demonstrated an unwavering commitment to quality, ensuring that every aspect of the extension was completed to the highest standards. His precision in measurements, choice of materials, and execution of design elements exceeded my expectations. Throughout the construction process, Blerim exhibited the utmost professionalism. He was always punctual and kept me informed about the project's progress. His communication skills are commendable, as he patiently answered all my questions and addressed any concerns I had. His ability to work collaboratively with me and the other contractors involved in the project contributed to a smooth and efficient workflow. One aspect of Blerim's work that I found particularly impressive was his reliability. He consistently met project deadlines and stayed within the agreed-upon budget. This reliability gave me peace of mind throughout the construction process, knowing that I could trust Blerim to deliver as promised. In addition to the extension, Blerim also transformed my outdoor space with his landscaping expertise. He took my vision for a beautiful and functional outdoor area and turned it into a reality. His landscaping work included planting trees, creating flowerbeds, installing a patio, and adding various hardscape features. The result is a stunning outdoor oasis that I now enjoy daily. In summary, I wholeheartedly recommend Mr. Blerim for any construction or landscaping project. His workmanship is exemplary, his professionalism is unmatched, and his reliability is unquestionable. Blerim's dedication to delivering top-notch results truly sets him apart, and I have no doubt that he will excel in any endeavor he undertakes.
ASC
Rating: 5 out of 5
Extension Builder in St James
Plumbing & heating — full professional range ASC HEATING & PLUMBING is based in London and works across London and the surrounding areas. With 6+ years in business, we offer everything from emergency call-outs and repairs to installations, leak detection, drains, bathrooms, boilers, central heating, underfloor heating and commercial plant rooms — planned so you know scope, timescale and cost up front.
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Latest review:
Plumbing- 1 Apr 2026
Aurel and his son did a great job, really knowledgeable and helped with a difficult job. Not only were the results fantastic but the guys were a pleasure to have around.

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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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 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.