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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mohamad abou ali
Rating: 5 out of 5
Extension Builder in St James
We deliver a wide range of design and build construction projects including: • Full House Renovations • Basement Installations • Extensions • Loft Conversions • New Builds Turn Key • Contract Site Fit Out Works • Commercial Premises Refurbishments
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Latest review:
Conversions - General- 19 Nov 2022
Very impressed with the work from Mohammad - very excellent work. Highly recommended.
VCKS
Rating: 5 out of 5
Extension Builder in St James
VCKS Professional service provided on time
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Latest review:
Tiling- 10 May 2025
Victor is excellent. Gave a competitive quote and stuck to it. Victor works quietly and thoroughly. The job was completed on time and to a high standard. I will use him again and I recommend him.
Complete Construction london
Rating: 5 out of 5
Extension Builder in St James
At Complete Construction we have a complete team to undertake all building and renovation works.We have been trading over 12 years,and forever growing.Priding ourselves on reputation and reviews and can offer plenty of references from recent clients.Having been known to have the team you want on your project,we are now being prided on our unbelievable Painting and decorating team
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Latest review:
Restoration & Refurbishment- 16 Jun 2023
Amazing job by Ross and his team! They're easy to deal with and the job was completed on time and to budget :) Will definitely use again! Thank you so much!
Pops Building Services Ltd
Rating: 5 out of 5
Extension Builder in St James
I am a city and guilds advanced craft qualified carpenter/joiner With over 30 years experience in the construction industry. I was the director of a property development company. I’ve managed contracts for NHS trusts as well as private contractors. The types of work I normally undertake are loft conversions, extensions, renovations, kitchen and bathroom installations
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Latest review:
Peter was the on-site foreman on our complete house renovation, which took just over a year. This included an additional ensuite pod bedroom in the roof and a side-return and extension to the kitchen. Peter was totally reliable throughout the project and thoroughly professional. Throughout this time we were living in the house with the children. He was always on time, managed the on-site team well and communicated clearly with us. His workmanship is high quality and he was also a stickler for checking the work of others and getting it updated if it wasn’t up to scratch. I have no hesitation in recommending Peter.
New Design
Rating: 4.7 out of 5
Extension Builder in St James
My name is Carlos, I have a construction company alongside my business partner and daughter Claudia. We are dedicated in everything related to painting, decorating, plastering, tiling, landscaping, flooring, interior finishings and general building works. We are professional, honest and hard-working individuals. Flexible and reliable builders with over 30 years of experience (operated in Spain and currently operating in London for more than 10 years). We guarantee we will not disappoint you. We offer ‘no obligation’ quotes. Photos and references upon request.
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Latest review:
Painting & Decorating- 3 Sep 2024
Great, reliable contractors. Had a full flat repaint job with some minor repairs (blinds fixing, handle replacement). Claudia was very efficient and responsive in communication. All was arranged pretty quick, appointment attended on time and kept to time schedule agreed. Had done a great job with repaint and provided reasonable rates. Also helped out with few minor repairs so I didn't have to get someone else. Very happy with the service , will certainly hire again. Thank you guys.
Victor & Co.
Rating: 5 out of 5
Extension Builder in St James
Victor & Co has operated throughout London successfully for over twenty years. We are determined to maximaze our customer’s satisfaction by fulfilling their wishes to their specification, rather than forcing a compromise. Our team is build up of successfully from disparate areas of the trade and together we have all the skills necessary to successfully carry out any work asked for us. We do have flexible approach to many issues ready to find solutions to most difficult matters.
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Latest review:
Extensions- 9 Nov 2021
I had a great experience hiring Victor & Co. They built a Rear Garden Extension in my house with excellent standards and finishing. Also they have done everything on time, which I know is quite difficult. I met Victor, the director of the project, every week to discuss the progress and any alterations to the original plans. He was great at explaining all the options and delivering the work. All the builders were very polite and you could see that they were very well organised with all the tools and building materials they brought to the house. When there were minor delays they were happy to come on weekends to catch up with the programmed finishing time. For the level of noise you could expect a building site can generate they were incredibly quiet. Last and not least, the quote I have from them was one of the most competitive ones I found in the market, so I can definitely recommend this company to anybody that is planning a big project.
Islington building services ltd
Rating: 5 out of 5
Extension Builder in St James
All building work undertaken (domestic only) Our company employees 12 people and fully qualified all skill men and 6 employees they have more then 15 years experience and 4 employees more then 10 years experience and 2 employees more then 18 years Jobs electrician and plumbeing and plastering and Joiner or Carpenter and Bricklay and roof .tiling (specialist kitchen and bathroom)
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Latest review:
Kitchen Fitting- 12 Sep 2021
Hassan and his team were excellent and worked really hard to complete my kitchen. I would recommend them to anyone. Thank you Hassan and team.
Estate Renovation (Al Huda Corporation Ltd)
Rating: 5 out of 5
Extension Builder in St James
Estate Renovation provides substantial building maintenance and development services, which include but are not limited to: kitchen & bathroom renovation, property refurbishment, extension, conversion, paint & decoration, electrical and plumbing services. Our main purpose is to provide your home with safety, comfort and beauty. We are prepared to face any challenges and always strive to achieve continual improvement of our values and standards during projects.
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Latest review:
Bathroom Fitting- 30 May 2022
Mohammed Huda and his builder were professional and quick to attend our job –– recommend! The communication was fast and professional. Mohammed provided a detailed quote (our job had to go through insurance) that is fair and transparent. The builder who came around, Jafa, was very respectful to our things. We were able to trust him from the get-go and had a peace of mind when he was working. He works incredibly hard and is methodical in his process (e.g. painting ceiling first, then walls, so to avoid splatter unevenness). They responded to our requests quickly and fixed things we weren't 100% happy with. The team finished the job ahead of time, and gave us tips for refurbishing in the future. Very happy and highly recommend!
Independent Building Services Ltd
Rating: 5 out of 5
Extension Builder in St James
We are an experienced construction company based in west acton. Quality work and reasonable prices, building maintenance, full renovation, extensions and loft conversions, design and advise plus much more . We will beat any prices and 100% customer satisfaction guaranteed.
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Latest review:
Extensions- 9 Feb 2019
I had the pleasure of working with Habib on the renovation of my house. My review of his work during renovation: 1- He has done excellent job in rewiring the house. he segmented each floor and kitchen and put them on separate ring, he expanded consumer box for future growth as well as installing wired smoke and security alarms 2,3 - He fitted pipe and installed unvented cylinder system with water softener perfectly including multiple heating control zones which I can control each floor individually (I love it). 4- he built a beautiful and prefect extension in garden, he considered all building regulations such as structural integrity, fire safety, energy efficiency, damp proofing, ventilation and other key aspects that ensure a building is safe. In addition to above he has very good personality and he is approachable to discuss changes or add new tasks to job (unlike some builders whom don’t like it). Throughout the course of the renovation, Habib was a consummate professional. He was accurate in his initial assessment of the scale and cost of my project. Good work takes time to complete. Patience is required when you work with a perfectionist. Although my project took time to complete, I have a wonderful outcome and a work of art now. I can recommend him highly and without reservation. Thank you, Habib, At the end I would like to thank Jake for his part and hard-working during renovation of my house. Hamid
Alpha Projects
Rating: 5 out of 5
Extension Builder in St James
I am a construction professional with a well-rounded background that spans from domestic refurbishments to super-prime residential projects. I began my career working on smaller projects such as bathroom and kitchen refurbishments, loft conversions, and house extensions, gaining hands-on experience in every stage of the build process. Over time, I progressed into managing and delivering high-end and luxury residential refurbishments, where precision, detail, and client expectations are at the highest level. My blend of architectural training and on-site experience allows me to approach projects with both design sensitivity and practical efficiency. I am skilled in budget management, construction programming with Powerproject, and the use of digital tools including Bluebeam, AutoCAD, and Revit to coordinate and deliver work to the highest standards. Whether working on a bespoke renovation or a large-scale development, I am committed to providing quality workmanship and a seamless client experience.
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Latest review:
We are absolutely thrilled with our recent kitchen renovation! The entire process, from start to finish, was incredibly smooth and efficient, issue that did arise were handled efficiently. The workmanship is truly top-notch, with every detail handled with precision and care. The team completed the project within an reasonable time frame and the quality of the final result has completely transformed our home. Thank you again to Umit and his team at Alpha Projects!
MB Healthy Design Ltd
Rating: 5 out of 5
Extension Builder in St James
* 3D Design * Bespoke Furniture * Kitchen/Bathroom Cabinets * Fencing * Shopfitting We provide high quality services with affordable prices.
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Latest review:
The price was very reasonable for the quality of work he delivered. He used high quality materials and tools, and did not cut any corners. I am satisfied with the final product.
pmlarc
Rating: 5 out of 5
Extension Builder in St James
We are RIBA registered architects with a wide range of experience of over 25 years within architecture, design and construction. We are experienced at new builds, full refurbishments, extensions and conversions, and have completed numerous residential and commercial projects in London and beyond.
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Latest review:
Architecture- 13 Apr 2015
We are extremely happy we chose to use Phil for our loft and extension design. Phil is professional, extremely accommodating and a pleasure to work with. He was always contactable, punctual and happy to spend a lot of time with us to discuss designs and the planning process. His design ideas were smart and he presented us with a number of workable options. We wouldn’t hesitate recommend Phil and would certainly use again for any architectural works.
Carl Mcinerney
Rating: 5 out of 5
Extension Builder in St James
Hi, I’m Carl. I’m 46 years old and have been in the industry since I was 16. We’re based in West London but have completed projects all over the UK over the last few decades. Our main clients have been predominantly based in Cobham on exclusive high end residence’s over the last 5 years, so we have a wealth of experience in fine detail finishing, cabinetry, structural and fit out, along with all other aspects. We’re happy to advise on all projects and complete to the highest standard.
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Latest review:
Carpentry- 31 Mar 2025
Very pleased now the job is completed 🙂
Dry lining and plastering.rendering
Rating: 3 out of 5
Extension Builder in St James
I have been doing this job more than 8 years for ather company And now i start working for my self nearly 2 years I guarantee 100% good job
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Latest review:
Plastering- 26 Jun 2025
Ben did a great palstering job at a very competitive price. It was very easy to deal with him. I have given him more jobs and will use him again
Vasile Balta
Rating: 5 out of 5
Extension Builder in St James
Thank you for reading this I’m Vas( owner of BALTA COMPLETE CONSTRUCTION LTD)from 16 started as a apprentice in construction industry, have work over the years on big projects also small ones , when I was about 30 years old whit lots of experience in house refurbishment, extensions and lofts , decided to open my business, it was the best idea I take Ower focus as a business is a hight quality service, on all projects(big or small) and the feedback from the profile prof this As a person in charge whit the projects, I’m very easy to talk to, friendly , also more than happy to sort issues out Thank you for reading this As a business ower focus is on quality, high end finishes and trat each coustumer whit respect, and live them happy after the project is finished
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Latest review:
Conversions - General- 24 Apr 2026
I recently had extensive work completed in my flat by Vas, and I couldn’t be happier with the result. The service was excellent from start to finish. Not only was the quality of the work consistently high, but the whole experience was smooth and stress-free. What really stood out was Vas’s level of skill and versatility. Every aspect of the project was handled with care and professionalism — from plumbing and new water heating pipes, to new electrics, installing a new kitchen, laying a beautiful wooden floor, renovating the bathroom, and even replacing doors with a sliding door system. Each element was completed to a very high standard. On top of that, Vas was friendly, proactive, and easy to communicate with throughout. Nothing ever felt like too much trouble, and it was clear he takes real pride in delivering great results. It was genuinely a pleasure to deal with Vas, and I would highly recommend his services to anyone looking for reliable, high-quality work. Thank you again!
Shpetim troka
Rating: 5 out of 5
Extension Builder in St James
Troka Construction specializes in home refurbishments, extensions, and a wide range of home improvements. With a focus on quality craftsmanship and personalized service, we bring our clients' visions to life with dedication and attention to detail.
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Latest review:
Carpentry- 30 Apr 2026
Great communication and was able to come and do the job quickly after first message. Job was completed to a great standard (skirting boards and some scotia)

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.