Extension Builders in St James

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.4 (19 reviews)

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Some of our top rated extension builders in St James

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Lezha Building Ltd
Rating: 4.9 out of 5
Extension Builder in St James
LEZHA BUILDING LTD Hello my name is Astrit. I’m the Director of the company We have a lot of experience in different trade so my business started in Italy but from 2015 we are based in london do not hesitate to contact no matter small or large work, we will reach you wherever you are.Thanks 🙏
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Latest review:
Tiling- 10 May 2019
As per the previous reviewer I don't usually hire tradesmen when there is only limited feedback, but given the glowing report I took the risk. And it proved to be a great decision. Astrit was great - clear communication, arrived when he said he would, sought our opinions on the key decisions and gave some great advice, before ultimately doing a great job for a reasonable price. A pleasure to deal with and will hire again for any future tiling work. Thanks Astrit.
MAG
Rating: 5 out of 5
Extension Builder in St James
We are a professional painting and decorating company based in London, delivering high-quality services for residential and commercial properties. We specialise in full bathroom renovations, including complete strip-outs, wall and floor tiling, waterproofing, and modern, high-end finishes. Alongside this, our skilled team also provides all types of painting, wallpapering, and interior decoration, with strong attention to detail and a clean, modern result.
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Latest review:
Handyman- 21 Mar 2026
Excellent communication throughout. Responded very quickly & kept me fully up to date. Needed a minor job doing, but ended up asking him to do more jobs.
Krots
Rating: 5 out of 5
Extension Builder in St James
Wood carpenter for doors, external rooms, ceilings, stairs, bedrooms, kitchens, railings and gardens
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Latest review:
Carpentry- 28 Sep 2025
Great handywork,
VORTEX SERVICES LTD
Rating: 5 out of 5
Extension Builder in St James
Vortex Trading Corporation Ltd, with over 25+ years staff and associates experience behind can offer our clients the best value for money in the property refurbishing fields. Our staff and associates having background with the Institute of the Federation of Master Builders, LABC (Local Administration Building Control), CSCS (Black Card), Party Wall Surveying, NTC-7 Qualifications, Masters in Project Management, and Qualified Architectural Designer and QS/Estimators. Offering turnkey project to clients.
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Latest review:
I had an extension built. The job was of a high calibre and professional standard and went to plan. Ross is well-organised, highly knowledgeable about building and construction, creative, dexterous, industrious, talented and has excellent problem-solving skills. He works professionally and is highly reliable. I strongly recommend Ross of Vortex Services Ltd to whoever is seeking building work done to his or her property.
Firfield Property Services Ltd
Rating: 5 out of 5
Extension Builder in St James
We specialise in renovations & refurbishments of residential properties in London. Our team arrive on time, are highly professional & polite and leave your home in pristine condition. **Free quotation and advice **All work guaranteed **Fully insured ** References available
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Latest review:
Handyman- 26 Aug 2014
The job went very smoothly and there were no problems. Twana, from Mark's team was punctual, professional and did the job exactly how we wanted it. We will certainly be using them again.
Yida Design and Construction Ltd
Rating: 5 out of 5
Extension Builder in St James
Yida Construction is a limited company based in Central London. We are a very reliable and professional team of tradesmen with over 10 years of experience in the building industry, committed to delivering the highest levels of quality and service to our clients.
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Latest review:
Restoration & Refurbishment- 26 Jun 2022
Tommy was a wonderful perfectionist and has done beautiful work in our stairway and hallway which had needed refurbishment for a very long time. It feels brand new. The flooring is perfect both in the hall and staircase, and the walls are now perfectly smooth and painted immaculately. Friendly and accommodating, we will be hiring again for more jobs in the future, undoubtedly. Thank you.
ALBERTHALL CONSTRUCTION LTD
Rating: 4.7 out of 5
Extension Builder in St James
I am and my team are all highly skilled builders with vast knowledge and skills. We have been in the construction industry for 15 years, specialising in extensions, loft conversions and whole house refurbishments. We are new to the MyBuilder portal, so are short on feedbacks. Therefore we will provide references from previous clients.
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Latest review:
Extensions- 13 Oct 2023
Sagar and Sanjeev are incredible- they are very diligent and really well versed in what they do! They know what they are talking about and are very friendly and incredible to work with. There was no issue that they weren’t able to help me through when it came to a complete renovation, extension and garden landscaping of my house. They are experts in what they do and they’re the only contractors I want to work with for any other works in the future. Would always recommend them. 100/100!
Planetium Construction Ltd
Rating: 4.5 out of 5
Extension Builder in St James
Im Adrian based on South West London and surrounding area ,Planetium Construction Ltd Will be your favourite .We have a trusted, friendly and professional team of tradesman with +10 years experience. Our aim is to provide on time full property maintenance and refurbishment to a very high standard at a competitive price ensuring our customers are completely satisfied.
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Latest review:
Bathroom Fitting- 2 Jan 2025
Extremely Disappinted with Planetium Construction- I hired Planetium for a 59k renovation job. Initially, the workmanship was acceptable only because I supervised closely and had them redo substandard work multiple times. However, before the job has been complete, I discovered already a roof leak in the master bedroom, direcly under the newly renovated bathroom. Despite my repeated requests, Planetium refused to take responsiblity or fix the issue. Just telling me need additional charges for the work. Worst still, Adrian the owner, demanded I pay the final balance of 1840 before they would address the GF heating which stopped working after they installed the new controller. When I reasonably refused to pay before they complete the job , Adrian swore at me over the phone the most offensive language. Furthermore, they promised to replace a new Miele microwave for the one they damaged during installation but now just walked away. Leaving me unresolved issues and additional repair cost!
Be-Studio Ltd
Rating: 5 out of 5
Extension Builder in St James
bé-studio is an award-winning interior design practice specializing in contemporary residential and commercial projects. We collaborate with a broad range of professionals to bring diverse projects to life, no matter the size, no matter the scope. Services Provided Architectural Design,Home Renovation, Interior Design, House Extension, Kitchen Design, Garden Design, Living Room Design, Home Extensions, House Plans, Complete Bathroom Renovation, Design & Build
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Latest review:
Bilal and his team designed the plans for the extension of the ground floor of our house. He invested time in understanding our ideas and needs, and translated them into something that is both inspiring and practical. They provided amazing visualizations for us to imagine the final look.I recommend Bilal and his colleagues for a hassle free and highly professional service.
Besar Construction Ltd
Rating: 4.8 out of 5
Extension Builder in St James
Hello from Besar Construction Ltd. With over 15 years of experience in construction and landscaping, we specialize in creating spaces that are both functional and inspiring. Our construction services cover everything from Building, Extensions and Renovation to high-quality finishing, always with attention to detail and durability. In landscaping, we focus on designing and building outdoor living areas — including decking, patios, fencing, driveways, pergolas, and garden structures — that bring comfort and character to every space. Each project is guided by craftsmanship, sustainability, and a vision of blending beauty with everyday living. We are proud of our dedicated team, who have successfully delivered over 100 landscaping projects and more than 40 construction projects, always with a commitment to craftsmanship, durability, and client satisfaction. We can’t wait to meet our new clients and start their next project. Thank you.😊
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Latest review:
Landscaping- 16 May 2026
Very professional quotation, I chose over two others because he was very clear on where extra costs may arise and was very straightforward. He advised a different finish than I originally thought I wanted with cut stone edges and it looks even better with his suggestions. His crew were very friendly and professional. Would definitely work with him again in the future.
Artnavix Design Limited
Rating: 5 out of 5
Extension Builder in St James
With over 20 years in the trade, we deliver high-quality refurbishments and finishes for both residential and commercial clients across London, mainly South Kensington, Chelsea, Mayfair, Surrey. I started on the tools as a labour with all trades, after decide work as a fully-qualified painter & decorator, spray painter and joiner, so I know exactly what good workmanship looks and feels like. After progressing into supervisor, site manager and project manager roles on projects ranging from high-end homes to large commercial fit-outs, I now run my own professional team. What we offer: Full internal & external painting and decorating, Airless spraying (fast, flawless finishes), All aspects of plastering, dry-lining and repairs, Bespoke joinery, skirting, architraves, doors and flooring, Complete refurbishments and renovations, Commercial office and retail fit-outs. One-stop solution Because we’ve built long-standing partnerships with trusted, fully-certified plumbing, electrical and home-automation specialists (including Lutron, Crestron systems), we can manage and deliver every aspect of your project under one roof – no juggling multiple contractors, no delays, one point of contact from start to finish. We pride ourselves on clear communication, keeping to programme, protecting your home or business, and leaving every job spotless. All work is fully insured, £10M liability insurance, completed to the highest standard and backed by genuine customer reviews. Whether it’s a single room refresh or a whole-property transformation, get in touch for a free, no-obligation quote – we’d love to help bring your project to life!
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Latest review:
Painting & Decorating- 13 May 2016
Alex and his team were amazing workers - worked late into the night on several occasions and always left everything so tidy They are all so skilled - they can do anything u need done - anything - brilliant all rounders The spraying of the kitchen is unbelievable it's like a brand new kitchen They also tiled for us and put up a new hood, installed a new worktop and put a new sink in - anything u need doing they can do and nothing is ever too much trouble for them In all the years we've been using tradesmen ( and we've done up several properties) they were the best, most hardworking, reliable, dedicated tradesmen I would recommend them to anyone We are so glad we found them as we will be using them for every job we need doing round the house Amazing!!!!
Tawfik Werfalli
Rating: 5 out of 5
Extension Builder in St James
At Miko Construction, we specialise in high-quality residential refurbishments, extensions, and fit-outs. We’re a small, experienced team that takes pride in delivering well-crafted work with clear communication throughout. Whether it’s a full home renovation or a bespoke interior project, we bring a personal, hands-on approach from start to finish.
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Latest review:
Tawfik’s team was very professional and very knowledgeable, they done a great work including helping me with the design and understanding the process required to complete a project at this size, he completed the electrical work tested it and also included great ideas with the LED lights that made A beautiful design at the end, he also recommended a lot of subcontractors in the area are very competitive in their price and practically manage the project with me from inception to completion.
Vision House Construction
Rating: 5 out of 5
Extension Builder in St James
What makes Vision House Construction the best option? At VHC qualified, experienced professionals are committed to delivering high-quality work in all aspects of home improvement with a satisfaction guarantee and affordable prices. We believe that strong buildings make strong communities. Our purpose is to help people enhance their space to live in safe, more efficient, and environmentally friendly houses.
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Latest review:
We’ve been really pleased with the work Samir has done for us. Throughout the project he was reliable, professional, and paid great attention to detail. The quality of the work was consistently good, and it was clear he cared about getting things done properly. What we appreciated most was that Samir was always willing to help and often went the extra mile to make sure everything was completed to a high standard. Communication was good throughout, and he was approachable and easy to deal with. Overall, we’d happily recommend Samir to anyone looking for a dependable builder who takes pride in his work.
Velvet Construction
Rating: 5 out of 5
Extension Builder in St James
About Velvet Construction: 5+ year experience in the building trade. CSCS Black Card Holder All health and safety certificates. Velvet Construction has a large team of qualified tradesmen, delivering a high standard of workmanship at a competitive price. For more information on our services please contact us. We offer free quotations and all work is insured and guaranteed.
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Latest review:
Restoration & Refurbishment- 10 May 2019
Velvet Construction are a friendly and professional contractor who work hard to deliver an excellent service. We have worked closely with them and their practical and dynamic approach is refreshing to work with in a professional capacity and we would highly recommend them. Their quality of workmanship is excellent which is largely driven by their own high standards which they monitor closely and consistently. They are organised and communication is always great. A big thank you to the whole team and Specially Negedet being a joy to work with . Highly recommend him and his hard work time. Thank you
Prodec Construction ltd
Rating: 5 out of 5
Extension Builder in St James
With over 16 years experience our reputation has developed very soundly as a specialist building contractor. We work on many types of projects including domestic houses, health care sector, and housing developers. Our service is designed around delivering the highest standard and quality.
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Latest review:
Painting & Decorating- 18 Jun 2025
Martin has done an excellent job for us. He is professional, polite and helpful.
3 plastering guys
Rating: 5 out of 5
Extension Builder in St James
London home developers take care and pride in our professionalism. We ensure minimal fuss for our customers and provide them with an end project of their exact want. London home developers are able to complete clients jobs such as Loft and extension, brick work, steel work, partitions, plastering, plumbing, luxury bathroom and much mor.
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Latest review:
Plastering- 12 Jul 2026
Rami did a great job repointing our walls and fixing cracks in our kitchen. Very pleased, quick and processional. Highly recommend. We will definitely use him again.

4.4

Top rated Extension Builders

Our Extension Builders in St James, are rated 4.4 out of 5 based on 19 reviews from customers like you.

Quality screening

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.