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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Miri G construction LTD
Rating: 5 out of 5
Extension Builder in St James
Hello everyone, I have 20 years experience in construction handyman, I have my team. We do Loft conversion Extension Brickwork Landscaping
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Venus Constructions Ltd
Rating: 5 out of 5
Extension Builder in St James
Hi, thanks for taking time reading.. our team at Venus Constructions specialises in all types of residential works and our range of services covers complete refurbishment, conversions, external buildings, patio, turf, driveway, decking, fencing, brickwork, blockwork, rendering. Depends of team member we have years and the necessary experience based on the works needed. Listening to the clients needs we assure with punctuality high quality results and workmanship of our friendly team.
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Latest review:
Landscaping- 28 Mar 2022
Gianni and his friend did an amazing job on our garden grass and planter. They came to see the garden before providing us with the quote. They were very professional, punctual thorough and quick. We were very impressed that they started the job the following day and that they were able to provide all the materials. We will definitely recommend them to friends and family.
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!
ArtInFacade
Rating: 5 out of 5
Extension Builder in St James
I’ve been working in the construction industry for 15 years, building a strong foundation of hands-on experience in both residential and commercial projects. Throughout my career, I’ve taken on roles ranging from general laborer to skilled trades, including roles like Roofing, Kitchen & Bathrooms fitting, framing, drywall, concrete work, etc. I’ve worked with a variety of crews and contractors, always contributing solid work and a strong work ethic. I’m currently based in London, but I’m available for jobs in surrounding areas and willing to travel for the right projects. I’ve worked in and out of London and have no problem taking on Projects of London when needed. My skill set includes: Reading and interpreting blueprints and site plans Extensions Loft conversion Kitchen & Bathrooms Framing, drywall installation, and finish work Concrete pouring and formwork Operating power tools and heavy equipment safely Site prep, demolition, and cleanup Strong knowledge of safety procedures What sets me apart is my reliability, attention to detail, and ability to stay productive without needing constant supervision. I take pride in my craftsmanship and believe in doing the job right the first time. I’m punctual, easy to work with.
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Latest review:
This contractor is very professional, friendly, and has a smooth finish. They’re probably one of the best in town, and they’re also affordable.
ALSOAA CONSTRUCTION LTD
Rating: 5 out of 5
Extension Builder in St James
⸻ Hello! I'm [mohammad], owner of [alsoaa construction ltd]. We have years of experience in home renovations and construction, and I pride myself on providing high-quality, exceptional customer service. Whether you need kitchen and bathroom renovations, painting and decorating, or custom tiling, my team and I are committed to making your vision a reality. We listen carefully to your needs and offer honest advice to ensure long-lasting results.
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Latest review:
Tiling- 29 Nov 2025
Recently had some tiles and splash backs put up. Excellent communications with Mohammad, his team was very punctual and professional the work was done to a very high standard. Pleased with the end result and will be using his service again. Highly recommended thanks again to Mohammad and his team.
professional polish builder(london)
Rating: 5 out of 5
Extension Builder in St James
I'm a builder (carpenter) with 19 years of experience in England. I do loft conversions and extensions - all building works. Carpentry and joinery is my main profession. I have a qualified bricklayer, electrician, plumber and others on my team who are happy to help. All works done by us coming with warranty and insurance.Dear potential client beware that we do not undertake structural building works without architectural drawings, structural engineer calculations etc. No time wasters please!
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Latest review:
Extensions- 26 Apr 2018
Professional Polish builders (london) ltd,?this is a suitable name for this company. They built an extension and loft for me in the time standards set. They aren’t a cheap service but the professionalism of this boys goes beyond and above. I’ve seen a lot in my life and it was the third extension I designed for myself as I’m architect. It is hard to find an honest builder who will tell you the truth about what is waiting for you during the works. The job was done relatively quickly even when I changed my mind a few times and the weather this winter was cruel but Adam and Martin were always positive so do not believe any one who gives a fixed price and time - it’s impossible to do. Adam and Martin are fantastic organizers and skillful professional builders, his team are friendly,very funny and hard working guys. Open minded guys who will tell you straight on what things you can save money on and what not to. My dog has fallen in love with them. Safety and common sense is a priority to the crew. I would recommend these boys to everyone. thanks for your help and hard work!
Elite Contracting Group LTD
No reviews yet
Extension Builder in St James
Transforming Spaces with Exceptional Decoration Works. With over 35 years of experience, Elite Contracting Group ensures the delivery of premium-quality finishes, with relentless attention to detail and reliable adherence to timelines. From designing possibilities to building realities, we work towards elevating interiors and exteriors and transforming your project into an exceptional work of art. Ultimately, we are devoted to the realization of your vision, as our mission is your satisfaction.
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22g construction limited
Rating: 5 out of 5
Extension Builder in St James
Hi , we are here on this platform to make your dream house into reality , with 20years of experience in all trades and expertise we will make sure you get the best service , so chose us for any kind of construction work . Thanks
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Latest review:
22g construction did my bathroom refurbished they did very good job more than my expectation I am happy to recommend 22 G construction anyone who’s looking refurbishment extension or any other work
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.
MGR Construction
Rating: 5 out of 5
Extension Builder in St James
Hi i have 12 years experience on this sector jobs that we undertake are full house renovation ,loft conversion Extension and Landscape.
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Latest review:
Fencing- 7 Oct 2018
Straight forward, easy to deal with, tidy, even removed an old shed for us. Would definitely use again.
Prestige Build and Management Limited
No reviews yet
Extension Builder in St James
We are a South-East London-based company that specialises in design, bespoke property redevelopments, refurbishment, extensions and loft conversions. We also do roof replacements and create stylish bathrooms and amazing kitchens.
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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
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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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.
Pioneer Concepts Ltd
Rating: 4.8 out of 5
Extension Builder in St James
Pioneer Concepts aim to improve the style, design and value of your property by offering design and build services that cater to all those needs. Pioneer Concepts can provide all building work services & technologies you require to transform your ideas and dreams into reality.
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Latest review:
Extensions- 24 Aug 2020
The end result was OK however there were numerous trust issues along the way which left a very bitter taste. For example we had rubble from another job they were working on, dumped outside our home and they denied knowing where it came from. Also they built over a sewer pipe without blocking it at all, which allowed rats to enter our property - they then blocked the hole with a black bin liner that the rats obviously gnawed through - then we were told the rats came in because of our standard of cleanliness! This would be a negative review however the end result was ok - it did come with a hell of a lot of stress though.
W&T Building Maintenance LTD
Rating: 5 out of 5
Extension Builder in St James
WT Construction Service LTD. has been in business since 2002 and we`re specialists in design, planning, structural, building service, house extensions, loft conversions, joinery and renovation work covering whole of London.We guaranteed high quality finish on competitive price. We`re signed FMB,TRUSTMARK
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Latest review:
William and his company fitted a new kitchen for me and did the painting and wallpapering as well. They did a professional high quality job within a short time. I was absolutely satisfied with their service and their prices. They work fast, clear and precisely. I would highly recommend them to anyone.

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.