Extension Builders in St James

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 St James

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Sergiu B
Rating: 5 out of 5
Extension Builder in St James
first and second fix of carpentry, furniture, plumbing, ...
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Latest review:
Job well done. I am very happy with the outcome. He gave good advice, knows his business, does good work and also helped out with other little things in the house. 100% positive I would recommend him to friends and neighbours
Bono Construction
Rating: 4.9 out of 5
Extension Builder in St James
BONO CONSTRUCTION is a family run building and construction company based in south east. 20 years experience in business we pride ourselves in the service we offer. We have our own in house drawing office and structural engineers. BONO construction will guide you through your project from very start to finish. ********We design cafes, shops restaurant from start to finish include extractor systems electrical fire cctv and even logo printed on your plates,cups get in touch for a quote
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Latest review:
Bathroom Fitting- 25 Sep 2018
Mustafa is excellent! He did a fantastic job on our bathroom - so much so, that when we decided on a more extensive construction project, he was our first call. He is communicative, friendly, and hardworking. All his team are sweet guys and they did a great job for a great price. I cannot recommend him enough.
Singh Delivers Ltd
Rating: 5 out of 5
Extension Builder in St James
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!
SM Refurbishment Ltd.
Rating: 5 out of 5
Extension Builder in St James
SM REFURBISHMENT LTD. is a well established company that has been in business for over 10 years and provides a comprehensive suite of building services. Our carefully selected team have a broad range of experience. If you are looking to extend, convert, refurbish or redecorate your property, we are here to assist you all the way from concept to completion offering individually tailored services. We are also specialists in carpentry and joinery projects as well as kitchen and bathroom refurbishment. We are FENSA accredited windows and doors installers.
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Latest review:
Restoration & Refurbishment- 21 Nov 2023
Slawek and Andrew did an amazing job on the front and side of our terraced house. The quote was fair (and they stuck to it) and the attention to detail was refreshing. We were kept informed throughout the works - communication was excellent. I whole-heartedly recommend SM Refurbishment.
Renovaze LTD
Rating: 5 out of 5
Extension Builder in St James
0% Finance Now Available. Spread the cost of our services today! Welcome to Renovaze. We Build extensions and carry out Full property Refurbishments including Bathroom design & Installation, Shower room design & installation and Kitchen installation. We are Clear, Transparent and Act with Integrity. Our huge reputation in providing excellence ensures you have peace of mind throughout the Project Journey. Get in touch and let us Renovate and Amaze you!
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Latest review:
Bathroom Fitting- 25 Jan 2022
Happy with work done to quality and agreed time line. Good communication throughout the 3 day job. Happy to recommend to others.
Leonard goli
Rating: 4.7 out of 5
Extension Builder in St James
Highty skilled construction with 10 years experience. Expertise in planning construction projects,defining scopes of work and labord costs. With plenty of experience in all aspencts of loft convention extensions barhrooms,kitchens,tiles,floor etc
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Latest review:
Decking- 1 Jun 2026
Extremely helpful and professional. Thank you
Razvan Consttruction Ltd
Rating: 5 out of 5
Extension Builder in St James
Razvan Consttruction Ltd is a company with a solid team of builders with experience of 20 years!
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Latest review:
We had a lot of work done including a brand new roof, whole rear and side extensions. New driveway. Landscaping. Complete fit out works inside. I wouldn’t hesitate to recommend Razvan- he is a complete professional and a really nice guy. Honest and hardworking and takes pride in his work. Out of all of the builders I have used Razvan is the only one I would use again.
BKFS LTD
Rating: 5 out of 5
Extension Builder in St James
Work undertaking includes; Joinery, Kitchen and bathroom installation. Electrical NIC EIC approved contractor Gas safe Plastering, Painting, Tiling, Specialised in Bespoke wardrobes. Granite, Marble and Quartz Worktops. Wet room
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Latest review:
Tiling- 3 Jan 2025
Job completed in a very friendly and professional manner. Highly recommended. Once again, thank you Raghed!
Pro Construction London Ltd
No reviews yet
Extension Builder in St James
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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GREAT UK CONSTRUCTION LTD
Rating: 4.9 out of 5
Extension Builder in St James
Welcome to GREAT UK CONSTRUCTION LTD! With 6 years of experience, we specialize in interior and exterior renovations alongside meticulous maintenance services. Our commitment to quality and innovation ensures excellence in every project we undertake.Thank you for choosing GREAT UK CONSTRUCTION LTD! Your trust in us fuels our passion for excellence.
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Latest review:
Bathroom Fitting- 24 Mar 2025
Open, Honest and good workmanship. Have got numerous other jobs done by Madalin - he is our go to person for any house projects! Thank You soooo much
BOILER ACADEMY LTD
Rating: 5 out of 5
Extension Builder in St James
team of Gas engineers and plumbers with years of experience we capable of doing all type of plumbing an heating work from replacing simple tap to whole hose New pipework
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Latest review:
Plumbing- 8 May 2019
Very quick and good job.
Beam Developers ltd
Rating: 5 out of 5
Extension Builder in St James
Unlocking a world of possibilities, BEAM Developer Ltd specializes in an array of dynamic property services. From sleek architectural designs for planning applications to robust structural packages, we've got your project covered. Our expertise extends to seamless renovations, repairs, and captivating new extension and conversion builds. Elevate your vision with BEAM Developer Ltd – where excellence meets innovation!
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Latest review:
Ahmad and the Beam Developers team did an amazing job on my rear extension. We were very particular with our requests and are generally picky people but they were very patient and accommodating to our every request. We were shown the drawings, made adjustments and managed to tailor the project exactly to what we wanted. The finished results were amazing. No big project for us soon but should we plan to do the loft will definitely use Ahmad and his team again.
Prime Construct Ltd
No reviews yet
Extension Builder in St James
Prime Construct Ltd are a Building Contractor in South London. Company Founder, Sam, set up the company having worked for a number of years at a large commercial developer in London. As a team we have a wealth of experience delivering projects from initial concept through to completion. As a small Contractor we provide great attention to each Client, to deliver high quality projects on time and budget. We look forward to working with you soon!
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Christian Andrews
No reviews yet
Extension Builder in St James
Carpentry and construction Fitted wardrobes Kitchens Extensions Renovations
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Ferati & Sons
Rating: 5 out of 5
Extension Builder in St James
With over 25 years of experience, we provide reliable, high-quality building services across the local area. We’re known for our attention to detail, clear communication, and getting the job done right first time. We specialise in: • Extensions • Groundworks & drainage • Conversions • Structural steel work (RSJs) • Rendering • Underpinning • Plasterboarding & internal works From small improvements to full property transformations, we manage every stage professionally and efficiently. We keep sites clean, stick to agreed timelines, and make sure you’re informed throughout the project. Most of our work comes from repeat customers and word of mouth - something we take great pride in. Get in touch today for a free, no-obligation quote and friendly advice
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Latest review:
Groundwork & Foundations- 11 May 2026
Excellent timing , communicated well explained everything clearly . Completed the job on the same day .
R baciu
No reviews yet
Extension Builder in St James
Designer and artist who conceives, design and creates luxury dwellings and runway clothing. in addition to dwellings Ramadan has designed restaurants, lounges and Luxury Clothing. If you have any questions, get in touch Flooring Tiling Plumbing Electrical Kitchen fitting Wardrobes fitting TV mounting Locks changing Shower fiting Taps changing And more
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4.2

Top rated Extension Builders

Our Extension Builders in St James, 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 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.