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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POLISH DECORATING SERVICES LTD
Rating: 4.9 out of 5
Extension Builder in St James
We are not the cheapest but we are Master Builders experienced in all aspects of building works including bespoke services. Dedicated team of craftsmen always deliver jobs to the highest standards. We provide full certification for any gas or electrical works. City&Guilds- N.V.Q., P.A.S.M.A. and I.P.A.F. Over 15 years of experience in the UK.
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Latest review:
Extensions- 11 May 2018
After a rogue builder left me with 18 (eighteen) structural issues. Lez and his crew came in transformed my failed extension into a masterpiece. All aspects of the job was done to the highest quality and utmost care and attention to detail was shown to building control needs. They cleaned up after every day and made sure the house was habitable, as I had to live there. Every aspect of the build, from the carpentry, plastering and tiling was first class and their recommend electrician and plumbers were from the same stock. Total professionals. My only regret is that I did not use this builder the first time. The prices were reasonable and even building control had good word to say about their work. Thanks Lez
M4A construction LTD
No reviews yet
Extension Builder in St James
M4a Construction is a reputable construction company based in the UK, providing a comprehensive range of construction services to clients nationwide. Our team of experts is equipped with the latest tools and techniques to ensure that every project is completed to the highest standards, our service include all general construction work.
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Construction
Rating: 5 out of 5
Extension Builder in St James
Carpenter Joiner:level 2 Diploma (blue CSCS) 10 years experience in UK 10 years experience back home (Romania) Level 2 Diploma in Electrical &Electronic Engineering Technology (QCF) CERTIFICATE of Attendance Waterproofing in Buildings (Delta Membrane Systems) Certificate of Attendance GRP Roofing (fibreglass flat roof installation) Construction Industry Scheme (sole trader registered)
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Latest review:
Carpentry- 17 Sep 2021
Viorel quoted promptly, arrived on time and did a a great job of the required carpentry jobs at my house - a cat flap and alterations to cupboards. I'm already talking with him about doing other jobs in the future so would definitely recommend Viorel!
Louisduckettbuilding LTD
Rating: 5 out of 5
Extension Builder in St James
I run a construction company, with over ten years of experience covering all aspects of construction and landscaping. we cover anything from as small as plasterboarding too extensions, we have a brilliant team of carpenters/builders which can carry out anything you desire from bespoke decking to fully functional garden room!
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Latest review:
Decking- 1 Sep 2020
What a great experience we had with Louis. He is honest and gets the job done efficiently with great attention to detail. He did such a good job with our terrace. We had some problems that really needed a professional solution and Louis planned and executed it brilliantly. Instead of looking for excuses for things that could be a problem Louis had a great solution for everything we came across and was positive the whole time. Would highly recommend Louis, we already have him booked in for more jobs.
M&I builders
Rating: 4.7 out of 5
Extension Builder in St James
M&I Builders Do it once,do it right! With over of 15 years of experience we can offer the package to provides stress free, time saving and cost effective solution to our clients to make the renovation project as easy as possible, with clear costing and progress plan..We are fully insured and considerable trade people fully qualified by BS to make your project up to current Standards. Your home is very important to us and measures we take to protect it is in the highest standards.
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Latest review:
Tiling- 24 Jul 2024
Job done perfectly, both builders are very professional, they care about the work and very experienced. Everything went smoothly with the tiling and flooring. They even installed extra kitchen cupboards:) Thank you both. I will be in touch for other jobs in the future. And recommended to my family
Novus Construction Limited
No reviews yet
Extension Builder in St James
Novus Construction Limited is a trusted building contractor dedicated to delivering exceptional service, high-quality workmanship, and reliable project management. We take pride in completing projects on time, within budget, and with clear, consistent communication throughout the process. To ensure your complete satisfaction and seamless communication, we assign a dedicated project manager to oversee every aspect of your project from start to completion. We specialise in a wide range of services, including but not limited to: • New Builds • Extensions • Loft Conversions • Refurbishments • Bathroom & Kitchen Fitouts • Carpentry & Joinery • Tiling If you’re ready to discuss your project or need expert advice, don’t hesitate to reach out. We’d be happy to offer a free, no-obligation quote and help bring your vision to life.
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Total Interior Solutions
Rating: 5 out of 5
Extension Builder in St James
Are you seeking a team who put your needs first? Then Total Interior Solutions is the team for you. We listen from the outset to what you would like your end result to be and this continues throughout the job which is completed to your complete satisfaction. Our team is ready to help you.
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Latest review:
Bathroom Fitting- 9 Jan 2015
Aggi and Pedro were excellent. They helped me to decide what fixtures and fittings I needed (including also doing some research themselves) and when it came to fitting the new bathroom they did it to a high standard and were tidy/cleaned up after themselves. I would recommend them.
Highpoint roofing and building contractors
Rating: 5 out of 5
Extension Builder in St James
At Highpoint roofing and building contractors we have over 40 years of experience Collectively, we take pride in our work to ensure 100% customer satisfaction With our free no obligation quotation you will be given all the advice you need to ensure total piece of mind our goal is to meet and exceed expectations of every customer all work carried out to the highest Possible standards and at very competitive prices
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Latest review:
Roofing (Flat)- 6 Jan 2026
Completed the job as promised and was very tidy in his job
One Take Solutions Ltd
Rating: 5 out of 5
Extension Builder in St James
Experienced plumber and handyman. Happy to provide fixed price, guaranteed work for tenants and homeowners alike.
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Latest review:
Plumbing- 4 Aug 2018
Able to fit an outside tap for us quickly and finished to a high standard. Very professional and passionate about the job. Also took a look at another plumbing issue we had and gave us an honest reply on what our best options were.
Mansarda Ltd
Rating: 4.9 out of 5
Extension Builder in St James
We are professional family run business. Our company specialised in loft conversions, house extensions home renovation, custom furniture and wood flooring in London. We have big experience in building industry with a lot of satisfied customers. Our service delivered by experienced people who will respect your property. All of our work is carried to the highest standard and we guarantee you a good price.
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Latest review:
Loft Conversion- 22 Sep 2021
Mansarda completed the work to a very pleasing standard and were reliable and well organised bringing in various specialists as and when required. Mykola was very flexible on making agreed variations to original plans to improve the final build. He is very knowledgeable and skilled in many aspects of the work. I would recommend him to anyone looking for a loft extension.
Brando Developments Ltd
Rating: 3.7 out of 5
Extension Builder in St James
Brando Developments, with a solid decade of trading since its establishment in 2012, has become a trusted name in the industry. Specializing in a range of services, we proudly collaborate with local estate agents, addressing diverse needs such as maintenance issues, end-of-tenancy work, and expert painting and decorating services. Our dedicated team includes skilled professionals, including gas engineers, electricians, and roofers, ensuring that we offer comprehensive solutions for our clients. With a proven track record, we continue to provide top-notch services, making property management and development a seamless experience for our valued customers.
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Latest review:
Bathroom Fitting- 10 Oct 2024
Really good team. The work was excellent. The only thing to comment is that the team could have finished the work faster but overall I’m happy with their work. Very involved and caring team. It felt like they were doing their own bathroom. Good price as well.
The london Loft and Kitchen Company
Rating: 4.5 out of 5
Extension Builder in St James
We are a southwest London Based loft and kitchen extension specialist. Our working area is very small with 90% of our jobs in Wandsworth and any work outside this area is never more than a mile or two away. With over 15 years experience in this area we know inside and out how these properties were built so when it comes to structural alterations you couldn't be in safer hands.
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Latest review:
Extensions- 16 May 2017
Initially apprehensive about using mybuilder, we found David easy going, clear and concise from the offset. The work carried out was to a high standard and any changes or questions that arose he was all to happy to answer. We found him to be pro-active in his approach, open and honest with how much items cost and sensible when agreeing monthly valuations. Both of us work in the construction industry and it is enjoyable and a breath of fresh air when you get to work with people as straight forward a David. We hope to do work with him again and would be happy to talk with anyone who is considering taking him on for additional work. Many thanks, Rob and Brom
Vukaj Construction
Rating: 5 out of 5
Extension Builder in St James
I have expertise in both formwork and finished carpentry. I excel in formwork, ensuring precise and sturdy structures, as well as in finished carpentry, where attention to detail is crucial to achieve high-quality, aesthetically pleasing results. My skills cover the entire spectrum of carpentry tasks
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Latest review:
Carpentry- 29 Jan 2026
I contacted Ekland and his brother Bes for some light refurbishment. I was so impressed with the work and speed that they ended up doing all the works I intended to do. Starting with latex screed, flooring using LVT system, architraves and skirting boards, installation of 9x heavy duty fire doors, carpets in 2x bedrooms and finally decoration. Prices were very reasonable considering the time and effort they put into installation but not only that, as I am a first time buyer they advised me on design as I didn’t really know where to start. They are honest and reliable, where I tried to save money they said it was not the right thing to do and took additional hours to make something right without a hidden extra. They turn up at 8am everyday and so easy to work with, I left them the keys to my flat and I didn’t need to check in on them at all. If you are thinking to do any refurbishment and are either hesitant or not knowing where to start these are your guys. 5* to Vukaj and thank you!
Fatos Shira
Rating: 5 out of 5
Extension Builder in St James
I have over 10 years experience in construction, I’m multi trader, I normally do brick work,extensions ,lofts, and ground work and more...
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Latest review:
Bricklaying- 18 Aug 2020
Fatos was an excellent choice. We agreed on a price and a date that was within the week and the price was very reasonable. Fatos also did an extra job for that he didn't charge me for even after I offered to pay him for. I was so pleased with Fatos job and experience that I am going to hire him to do more jobs for me. He was definitely one of the good ones excellent workmanship and trustworthy
R3 PLUS LTD
No reviews yet
Extension Builder in St James
R3Plus is a small construction company based in England, founded with the goal of delivering high-quality services in the construction industry. Since our inception, we have aimed to build with dedication and care, creating projects that reflect professionalism and a commitment to quality. With a dedicated and experienced team, we serve the needs of our community and clients by providing customized construction solutions
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M&J Home Construction LTD
Rating: 5 out of 5
Extension Builder in St James
Dedicated team, hands-on everything with more than 15 years experience on the market, we can prove that small things can creat great expectations. Our team is dedicated to perform the perfect job for you from simple handy work to Plumbing, Electrical, Kitchens and Bathrooms, , Flooring, and many others. We cover London and 10 miles radius,
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Latest review:
Bathroom Fitting- 23 Apr 2026
M&J done a great job redoing my whole bathroom and fitting in all the new tiles and shower units along with basin and toilet. If you are in doubt take this review as your reason to book this team in to get a fantastic job done.

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.