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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HOME DESIGN 4 YOU LTD
Rating: 4.8 out of 5
Extension Builder in St James
Working closely with our clients, Home Design 4 You provides a Single Point One-Stop, Innovative Architectural, Creative Interior - Bespoke Design, 3D Visualisation, Project management and Design & Build services for all types of residential development and Home Improvement projects.
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Latest review:
Extensions- 19 Jun 2016
Neno is a very warm-hearted and genuine person. He gives his 100% to the job. He is also very prompt when it comes to communication and is always available by phone/text/email. He has a vast experience and good technical know-how and produced excellent plans and drawings. His quotes were very reasonable and offer excellent value for your hard earned money. Having been his client, I am genuinely inclined to believe he is a person who would never "rip off" his clients. He is a man of his word and does what he says. However, Neno's honesty and confidence can be a bit blunt at times. He can be quite “direct” with his opinions and this may rub off some people the wrong way, e.g. your local Council Planning officer may be an a**hole, but if you "confront" him, he will definitely not make things any easier for you- nevertheless, Neno dealt with all the Council red tape and followed up the Planning Permission Application to its conclusion. We finally got permission for extending the property much less than what we had expected initially- apparently our local Council (Hillingdon) has its own set of Draconian conservative rules that we were unaware of- but we have postponed the actual project work due to a recent change in personal circumstances. Summary: Based on my personal experience, I would DEFINITELY RECOMMEND Neno as a bona fide Tradesman on MyBuilder.com.
FSB Company (UK) LTD
Rating: 5 out of 5
Extension Builder in St James
FSB is a well-organized contracting company with a team experienced in large-scale development projects with leading UK construction companies. Based primarily in London, we offer a variety of self delivered services, including complete extensions, and conversions, small works, structural alterations, steel work installations, ground work (foundations, drainage, concrete sub and superstructures), hard landscaping and paving and soft landscaping. We manage our sites carefully and have a digital site management tool kit. Our fully managed service connects skilled tradespeople with experienced construction management directly ensuring attention to detail that begins with our Contractors Proposals and continues through to practical completion and aftercare.
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Latest review:
Extensions- 17 Nov 2025
Freddie, Kaz and Dan are a great team. I felt they were friendly and professional throughout. Any slight niggles were discussed and solutions found, quickly and professionally. They were respectful and went out of their way to get on with all the neighbours. Over all I would say they are a team of very nice people, who care about what they do and take pride in achieving the result their clients are after.
Designs and Developments
Rating: 5 out of 5
Extension Builder in St James
At Designs and Developments we have a wide variety of services ranging from bathrooms, kitchens, flooring, decorating loft conversions and extensions.
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Latest review:
Kitchen Fitting- 31 Jul 2019
To say Nick is just a kitchen fitter isn’t doing his work justice, he’s a fantastic project manager and craftsmen as well. When we first met Nick he took 2 hours of his time running through all the options which was when we realised we were actually quite clueless! Although we hadn’t hired him at this point his advice was invaluable. We assumed this would mean Nick’s professionalism would mean he would be very expensive, this was not the case and he was actually a little cheaper than the other parties who quoted. Once Nick started it became apparent that he and his assistant Chow to great pride in their work and worked hard to get the job finished as quickly as possible to the highest standard. They left the site spotless at the end of each day. The result is a fantastic kitchen and flooring which we are extremely happy with. We are already thinking about the next renovation piece in our home and would love to use Nick again. Thanks Nick! Niall & Hannah
Sam
Rating: 5 out of 5
Extension Builder in St James
Comprehensive Experience in Construction, Kitchen Installation, and Other ServicesDear Sir/Madam,I would like to share with you my extensive and comprehensive experience in the field of construction, including kitchen installation and repair, tiling and carpentry, plumbing, electrical work, as well as building and bathroom renovation.I have been working in this field for several years, successfully executing a variety of projects, both small and large, in different sectors such as residential, commercial, and educational buildings. I have provided my services to several satisfied clients and have always strived to achieve their complete satisfaction by delivering high-quality work within specified deadlines.My experience is characterized by skillful leadership of work teams and coordination of efforts among different technicians to ensure efficient and effective project execution. I am constantly seeking to develop my skills and learn from my experiences to deliver the best in every project.If you are looking for a specialized and reliable professional to execute your project, I am here to serve you. I am honored to offer you my services in the fields of construction, kitchen installation, and others, and look forward to working with you to achieve your goals and meet your needs.Thank you for your trust, and I look forward to the opportunity to collaborate with you.Best regards, [sam]
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Latest review:
Good job.Outstanding worker.
Cambridge group
No reviews yet
Extension Builder in St James
We are a trusted construction team with over 10 years of professional experience delivering high-quality building services across residential and commercial projects. Our goal is simple: to provide reliable workmanship, clear communication, and results that exceed expectations. Over the past decade, we have successfully completed a wide range of projects, including: • Home extensions & loft conversions • Full property refurbishments & renovations • Kitchen and bathroom installations • Carpentry and joinery work • Plastering, painting, decorating & tiling • Roofing, brickwork & structural modifications • Driveways, patios & landscaping • General maintenance and repairs Our portfolio includes dozens of completed projects, each finished with attention to detail, high-quality materials, and a commitment to customer satisfaction. We take pride in our craftsmanship and treat every job—big or small—with care and professionalism. Why choose us? • 10+ years of hands-on industry experience • Skilled, fully insured, and reliable team • Transparent quotes and regular updates • Clean, safe, and well-organised working practices • Strong portfolio and repeat customers We work closely with every client to understand their needs,
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Tap 2 Loo Plumbing Services Ltd
Rating: 5 out of 5
Extension Builder in St James
I am a tradesman that has fifteen years of experience in all aspects of construction. Building extensions, loft conversion, kitchen fitting , bathroom fitting, refurbishments and fiberglass roofs
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Latest review:
Kitchen Fitting- 13 Apr 2023
Thank you Kyri (and team), I’m very pleased with my new kitchen and highly recommend your work, your attention to detail is outstanding and made a huge difference to the finish. A lot of preparation work was needed but it was worth it in the end and I’m very happy.
GM Construction
No reviews yet
Extension Builder in St James
Our range of construction projects include kitchens & bathrooms, refurbishments, loft conversions and extensions. We project manage our work and believe that good clear communication with our clients is key to a successful project- from our first consultation visit, throughout the quotation and build process. We want our clients to be delighted with both the quality of our work, and the manner in which it is carried out. We look forward to hearing from you soon!
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Interior design project ltd
Rating: 3 out of 5
Extension Builder in St James
Company business interior design project Ltd ,and we undertake loft conversion extensions plumbing electrical Ensuite Kitchen fittings bathroom fittings for timber framing carpeting Ground works gardens and landscaping driveways Gard walls suspended ceiling joist framing RSJ framing And many more
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Latest review:
Extensions- 3 Oct 2022
I gave him the opportunity as I was desperate to find someone fast,and didn’t have much success on here.Soon as he accepted,he was already asking for cash beforehand to get materials.I thought you know what,his company details are online,what can go wrong so I did.As his team started the job, they told me I needed to have 2 fences erected as they were badly damaged and deteriorating.I thought heck,why not,might aswell do it now so I gave him again, the opportunity to make some extra business with us.Again,was asked for some pre payment to get the materials,all in cash.All was finished within 2days of the weekend.Fence looked fine,but the roof just looked like a cowboy job.I didn’t complain,as it was done fast,with all the stress with opening a new business,it was one less headache out of the way.After 1 day of rain,the roof was already leaking,like absolutely everywhere.Called him, and he got someone to come by a few days after to fill in more silicone.(Very suspect job again).I thought fine, aslong he’s responding and trying to fix the situation.Fast forward few days later, bearing in mind the shop isn’t open and I’m not always there when it’s raining,it rained again and it was leaking in some areas again.Whatsapped him which is how we normally communicated,called him,read my messages but no reply. Now he has blocked me.Seriously, how he knows I’m opening a business soon this is how he wants to treat his customers. Simply give me back my money or fix the problem, simple!
Lombardo Constructions Ltd.
No reviews yet
Extension Builder in St James
Our target is the full client satisfaction. Lombardo Construction has been trading for more than thirty years in the construction and restoration market. We have been always oriented towards the research and the innovation during design and construction phases with a precise care for details and quality control process. The company is able to offer to the client the know how in restoration, renovation and new built works for the required M/E services along with the statutory certification.
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Dariusz Zaczkowski
No reviews yet
Extension Builder in St James
Extension Loft conversion Bricklaying Roofing Demolition Porches and Conservatories Kitchen fittings BENCHMARX, HOWDENS and much more Floors, doors, windows, wardrobes, partition walls, shelving, fittings Decking Any aspects of plumbing Bathroom refurbishment Any aspect of electrical work Also interior and exterior decorating, plastering, painting All our work is insured For free estimates
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Builds the thrills LTD
No reviews yet
Extension Builder in St James
Hi
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Safeway Build Ltd
Rating: 5 out of 5
Extension Builder in St James
At Safeway Build Ltd, we pride ourselves on delivering exceptional craftsmanship and reliable service in every project we undertake. Led by Florin, a highly trained professional with over 20 years of experience in the construction industry and a proud member of the Federation of Master Builders (FMB) since 2014, our company is built on trust, quality, and attention to detail. Working alongside trusted electricians and plumbers, we offer a complete service that ensures every aspect of your project is handled with care and expertise. Much of our success has come from referrals and repeat clients, a testament to the satisfaction and confidence our customers have in our work. At Safeway Build Ltd, we don’t just build — we build lasting relationships, turning your vision into reality with professionalism, transparency, and dedication. Whether you are looking for loft conversions, extensions or a refurb, all our services are carried out carefully, efficiently and to an exceptionally high standard of quality. We are happy to undertake any domestic work. At Safeway Build Ltd, no job is too big or too small.
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Latest review:
Kitchen Fitting- 10 Feb 2026
Florin and team were a joy to work with. Very communicative and worked to a great timeframe. Lots of little extra jobs were completed at no extra charge. Cost for job was reasonable and the tiling was immaculate - would definitely use Florin again. Would highly recommend!
Huseco Limited
Rating: 3.7 out of 5
Extension Builder in St James
HUSECO Limited is a well-established family business specialising in domestic renovation and construction projects. Our portfolio of skills also includes architectural design, interior design, and planning, which allows for stylish renovations, extensions, lofts, and modern living spaces. We have a loyal team of highly skilled builders, and the dedicated project manager personally oversees all our projects
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Latest review:
Extensions- 14 Sep 2025
How long should a 3m extension take if drawings were approved in April, the conservatory was demolished, the foundation completed, and the steel structure was already on site by May.?
Nice Design & Build
Rating: 5 out of 5
Extension Builder in St James
Quality general builder
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Latest review:
Decking- 16 Apr 2022
Adam is firstly a really lovely guy and we felt comfortable with him from the moment he came and did a very thorough assessment of the job. His work was very neat and clean. The job was done perfectly and we will definitely be using his services for other work on the flat.
Nilo Construction Ltd
Rating: 5 out of 5
Extension Builder in St James
Nilo Construction LTD is a 🏗️DESIGN & BUILD company specialising in FULL HOUSE RENOVATION, EXTENSIONS, LOFT CONVERSIONS & BESPOKE JOINERY With our in-house team of highly skilled Multitraders, project managers, designers and architects, we have the expertise to bring even the most complex projects to life. We are fully insured and qualified, ensuring both safety and quality in every aspect of our work. The feedback from our previous clients speaks for itself, reflecting our commitment to excellence and customer satisfaction. With a wealth of experience and a team of professionals, we are the ideal partner for both residential and commercial development projects.
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Latest review:
Conversions - General- 3 Nov 2024
Igor, Zhan and team were fantastic. Communication was great start to finish and they completed the job to a high standard on schedule
Diti building & Construction Ltd
No reviews yet
Extension Builder in St James
Our company takes pride and joy in the high quality that we prove. We strive to achieve highest levels of work for our clients which has been the case for over 20 years of experience in construction. We do everything from loft conversion, extensions, full refurbs, bathroom, kitchens. We are proud to say that our work has spoken for us throughout the years and will be glad to show older projects of our quality works. So feel free to contact us for any questions or query’s, we’ll be happy to accommodate you and take your projects on. We have a full team builders , electricians, plumbers, carpenters, tilers, painters and we have our architects and engineers that we works closely with. We hope to take on your projects and give you an amazing experience throughout the process and give a top quality finish all all works taken on. TikTok name DBC Instagram name DITI Building & Construction Ltd Where you can see my jobs some of them
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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 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.