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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Christian Andrews
No reviews yet
Extension Builder in St James
Carpentry and construction Fitted wardrobes Kitchens Extensions Renovations
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Prime Construct Ltd
No reviews yet
Extension Builder in St James
Prime Construct Ltd are a Building Contractor in South London. Company Founder, Sam, set up the company having worked for a number of years at a large commercial developer in London. As a team we have a wealth of experience delivering projects from initial concept through to completion. As a small Contractor we provide great attention to each Client, to deliver high quality projects on time and budget. We look forward to working with you soon!
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HCI CARPENTRY & CONSTRUCTION LTD
Rating: 4.9 out of 5
Extension Builder in St James
HCI CARPENTRY & CONSTRUCTION LTD has a proven track record of innovative designs, effective problem solving and attention to detail and our goal is to meet and exceed the expectations of every customer. We take on all types of jobs from small domestic work to larger commercial projects, all carried out to the highest standards, and at very competitive prices.
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Latest review:
Carpentry- 9 Oct 2024
The guys did a great job installing our bannisters and cleaned up afterwards which was brilliant! Will be using them again if we need anymore joinery.
Beam Developers ltd
Rating: 5 out of 5
Extension Builder in St James
Unlocking a world of possibilities, BEAM Developer Ltd specializes in an array of dynamic property services. From sleek architectural designs for planning applications to robust structural packages, we've got your project covered. Our expertise extends to seamless renovations, repairs, and captivating new extension and conversion builds. Elevate your vision with BEAM Developer Ltd – where excellence meets innovation!
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Latest review:
Ahmad and the Beam Developers team did an amazing job on my rear extension. We were very particular with our requests and are generally picky people but they were very patient and accommodating to our every request. We were shown the drawings, made adjustments and managed to tailor the project exactly to what we wanted. The finished results were amazing. No big project for us soon but should we plan to do the loft will definitely use Ahmad and his team again.
A1 home improvement London Ltd
Rating: 4.9 out of 5
Extension Builder in St James
Welcome to A1 home improvement London ltd, Our family-run company is dedicated to providing top-quality construction, renovation, landscaping and roofing services to our clients. With a focus on integrity, excellence, and customer satisfaction, we strive to bring our clients' visions to life while exceeding their expectations. Combined our team has more than 35 years of experience. We provide all our clients with the highest standard of workmanship, unbiased advise and competitive pricing.
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Latest review:
Roofing (Flat)- 24 May 2026
Martin came and saw the job promptly. His quote was a little more than another I had had but he made a couple of suggestions and generally demonstrated he knew what he was talking about so I chose him. The job was done quickly and well in a day. It hasn't rained heavily yet but the roof seems perfect. Martin did say that if there were any problems to call him. I am sure everything will be fine but it's nice to have that kind of customer service. Highly recommended!
R baciu
No reviews yet
Extension Builder in St James
Designer and artist who conceives, design and creates luxury dwellings and runway clothing. in addition to dwellings Ramadan has designed restaurants, lounges and Luxury Clothing. If you have any questions, get in touch Flooring Tiling Plumbing Electrical Kitchen fitting Wardrobes fitting TV mounting Locks changing Shower fiting Taps changing And more
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Ferati & Sons
Rating: 5 out of 5
Extension Builder in St James
With over 25 years of experience, we provide reliable, high-quality building services across the local area. We’re known for our attention to detail, clear communication, and getting the job done right first time. We specialise in: • Extensions • Groundworks & drainage • Conversions • Structural steel work (RSJs) • Rendering • Underpinning • Plasterboarding & internal works From small improvements to full property transformations, we manage every stage professionally and efficiently. We keep sites clean, stick to agreed timelines, and make sure you’re informed throughout the project. Most of our work comes from repeat customers and word of mouth - something we take great pride in. Get in touch today for a free, no-obligation quote and friendly advice
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Latest review:
Groundwork & Foundations- 11 May 2026
Excellent timing , communicated well explained everything clearly . Completed the job on the same day .
Singh Delivers Ltd
Rating: 5 out of 5
Extension Builder in St James
I love to install carpets. Carpet isn’t just a floor but a lifestyle. I specialise in carpet fitting and maintenance. I tend to provide quality work for clients through years of experience. Every job requires a coordination between client and company, and this is how I work by coordinating with client because end of the day client would be looking at work and shouldn’t have any second thoughts.
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Latest review:
Painting & Decorating- 23 Feb 2026
Good job, delivered fast at a good price. Many thanks!
Bono Construction
Rating: 4.9 out of 5
Extension Builder in St James
BONO CONSTRUCTION is a family run building and construction company based in south east. 20 years experience in business we pride ourselves in the service we offer. We have our own in house drawing office and structural engineers. BONO construction will guide you through your project from very start to finish. ********We design cafes, shops restaurant from start to finish include extractor systems electrical fire cctv and even logo printed on your plates,cups get in touch for a quote
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Latest review:
Bathroom Fitting- 25 Sep 2018
Mustafa is excellent! He did a fantastic job on our bathroom - so much so, that when we decided on a more extensive construction project, he was our first call. He is communicative, friendly, and hardworking. All his team are sweet guys and they did a great job for a great price. I cannot recommend him enough.
JKBC
Rating: 5 out of 5
Extension Builder in St James
By having 20 years of experience in the business, no job is too challenging. My team specialises in both small scale repairs and decorating, as well as major projects such as refurbishments, extensions, and home renovations.
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Latest review:
Jerzy carried out several jobs for us. He has completely refitted our bathroom, he's rebuild a wall, laid front of house path, restored old front door, installed solid wall internal insulation, rebuild window frames, plastered a room and few other bits and pieces. He is extremely reliable and trustworthy. He's always been on time, works really hard and has always been honest about things and up front with any issues. Always consulted us for possible solutions. His work is to the highest standard and if I want a job done well, I always go to Jerzy.
Mark
Rating: 5 out of 5
Extension Builder in St James
A professional service with over 10 years experience, covering all areas of London and surrounding areas. Gardening. Painting. Bathroom fitting. Fencing. Carpet cleaning. Etc. Free quotes and a 24/7 call out available.
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Latest review:
Fencing- 26 Mar 2022
Mark was polite and friendly, and did the job of repairing our fence really quickly and very well. Happy to recommend
Akili_handyman
Rating: 5 out of 5
Extension Builder in St James
Hi, I’m Akili — a friendly, reliable tradesman with over 8 years’ experience. I take pride in high-quality work at fair prices, and I guarantee all my jobs. Skilled in plastering, tiling, decorating, roofing, and full refurbishments — no job too small or big. Quality, honesty, and respect in every project. 👍
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Latest review:
Restoration & Refurbishment- 8 Jul 2026
Very happy working with Akili. Love his attention for details. Highly reccomended!!
Naksh construction ltd
Rating: 4.3 out of 5
Extension Builder in St James
We are a highly skilled, competent, and professional team of builders at Naksh Construction Ltd. We offer all the building services you could require, including additions, new construction, basement conversions, new residential or commercial construction and renovations of your existing bathrooms, kitchens and residences. Not only do we complete this task quickly and professionally, but we also take care to ensure that every job we complete is sophisticated, elegant, and meets your demands and specifications."
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Latest review:
Extensions- 7 Apr 2025
Quotes were provided and the job was agreed upon. The project involved a full house restructuring and extension build. However, after several stages of work, communication with Jas was lost, and his co-worker took the lead on site. Several issues arose, such as recommending smart plumbing equipment for purchase, but their plumbers were unable to install it. The tiling, skirtings, and tiles were not completed. Tiles around the columns were cracked. After Jas's team abandoned the project, another plumber had to install all the remaining items. The job was left unfinished, and we had to find alternative contractors to complete it. Significant time and money were wasted due to persistent communication problems, failure to issue invoices, and numerous other issues. Eventually, Jas and his main labourer stopped responding and disappeared, ignoring phone calls and WhatsApp messages. Be aware of these potential issues.
PD Construction Services Limited
No reviews yet
Extension Builder in St James
We deliver high quality domestic refurbishment services in all of London and the surrounding areas. We undertake all building work include: House Extensions and Conservatories Loft Conversions Full House Refurbishment General Building Joinery and Carpentry Painting, decorating Bathroom remodeling Kitchen refurbishment Foundations Garage conversions Residential Renovation Electrics and Plumbing Patios, paving and fencing
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Fk skyline LTD
No reviews yet
Extension Builder in St James
FK Skyline is a London-based construction company specialising in loft conversions, extensions, and full property renovations. We deliver high-quality workmanship, reliable timelines, and clear communication from start to finish. Our team is experienced, professional, and committed to meeting clients’ expectations while maintaining excellent standards of safety and cleanliness. We take pride in providing honest pricing, attention to detail, and customer satisfaction on every project.
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Ceca Developments LTD
Rating: 5 out of 5
Extension Builder in St James
Hael Construction Ltd, a proud member of the Federation of master builders, is a trusted construction company based in North London, delivering high-quality building services across the region. We specialise in new builds, extensions, loft conversions, renovations, groundworks, electrical installations, and plumbing. With a skilled team of qualified tradespeople and experienced project managers, we provide a complete service from design to completion. Our focus is on quality workmanship, transparent communication, and delivering projects on time and within budget.
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Latest review:
Extensions- 23 May 2022
Ceca Developments have done an outstanding work on our side and rear extension project, and we would definitely recommend this company. Firstly, they have offered a really competitive quote for the work and have been very transparent and detailed in regards to how long it will take to complete the project. Sebastjan has been a pleasure to deal with and was very helpful during the project, providing honest and useful recommendations and being available every time we needed anything. All the work has been completed to a very high standard and to the agreed timelines. We did not have to worry about anything during the whole project, which made this a very pleasant experience.

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.