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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London city builder
No reviews yet
Extension Builder in St James
London City Builders (LCB) is a professional who specialises in designing and creating stunning interiors for high-end homes. We have a deep understanding of the latest trends, materials, and techniques in interior design and can transform any living space into a beautiful and functional work of art.
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Botnari Construction
Rating: 5 out of 5
Extension Builder in St James
Botnari Construction. Every project is unique to every homeowner with small details having significant importance. What matters to our clients is what matters to us and these are the problems that we like to solve. We specialise in all Construction works with many years being in the industry, making sure we deliver a fast, efficient and well-organised project at its best.
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Latest review:
Botnari Construction recently completed a project for me and I was extremely impressed with the way they work. From the quality completed to great time management I was very happy with the works carried out. Will definitely be using in the future. 10/10
B&K
Rating: 5 out of 5
Extension Builder in St James
B.K. Building & Renovation is a family-run building and renovation business based in South Harrow. We provide reliable, high-quality work across extensions, brickwork, blockwork, plastering, painting and decorating, tiling, flooring and general property improvements. We take pride in clean workmanship, clear communication and attention to detail from start to finish. Whether it is an internal renovation, plastering and finishing work, brickwork, flooring or a larger building project, we aim to complete every job safely, neatly and to a professional standard. Customers choose us for our reliable service, respectful approach, tidy working habits and commitment to quality. We treat every property with care and work hard to deliver results our customers are happy to recommend.
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Latest review:
Benjamin and his team did a fantastic job on my property building a 6m by 6m Extension walls in only 2 days, it was done ahead of time and on budget. He was very conscientious and nothing was to much trouble. Done all the pictures of each step along the way needed for Building Control Guy. The quality and workmanship was first class and I would definitely recommend him for all types of building/refurbishment work.”
Bendev Construction 2018 Ltd
No reviews yet
Extension Builder in St James
Family business with experience in new builds, extensions and refurbishments
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Damian Construction
No reviews yet
Extension Builder in St James
We are experienced building company with over 20 years of experience specialising in high quality, luxury renovations and buildings extension projects, serving all London private and commercial home owners. Using only best materials available, together with our innovate designs with traditional values and workmanship, we make sure that we offer the highest build quality at an affordable price.
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M R CARTER BUILDERS Ltd
Rating: 5 out of 5
Extension Builder in St James
I have been trading since December 2015 and personally have over 25 years of electrical and civil engineering and construction experience. The Company has been NICEIC reg from March 2016 and undertakes all electrical work and Certification services . We are fully insured and we have a fully qualified team of construction experts , we undertake full renovations and extensions , with all building control and certification adhered to by the letter , working with you to give you what you want .
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Latest review:
Extensions- 21 Jun 2020
I found Mark to be a thorough professional always on top of things. Most enjoyable and a pleasure to work with him . I will definitely recommend him. ⭐️⭐️⭐️⭐️⭐️
OGC LANDSCAPING LTD
Rating: 5 out of 5
Extension Builder in St James
Welcome to OGC Landscaping, I'm based in South East London/ Kent and have experience in landscaping and general handyman work, I pride myself on my work and always strive to deliver the best customer service, I treat your home as if it was my own and I am honest, friendly and very reliable, please take the time to have a look at my work and the finished job can really transform your home or garden. I provide free estimates and helpful friendly advice. Here are some of the services I offer and look forward to hearing from you. Services Indoor/Outdoor Landscaping and groundworks Turfing Brickwork Shed bases Decking Hard landscaping Garden design Summer house design & construction Garden sheds Sleepers Flower beds Tree planting Soft landscaping I'm happy to offer a flexible service at a time that suits you, please don't hesitate to get in touch. If for any reason you are unable to contact me send me a text and ill get back to you as soon as possible. Many thanks Oliver
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Latest review:
Landscaping- 5 Oct 2025
Amazing work and communication
Plumber
No reviews yet
Extension Builder in St James
Hi my name is Gledis. I am a plumber, also I am very good at landscaping, flooring, extensions, bathroom fitting, painting and gardening. I have a lot of experience on the construction industry, also I do a bit of carpentry (installing doors, partitions etc) I am always on time, very good at communicating and understanding whats the budget of the costumer and knowing what they want.
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LIVAHAUS
Rating: 5 out of 5
Extension Builder in St James
We are a professional team and we are very responsible, punctual and on time with our work .
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Latest review:
Tiling- 16 Feb 2026
Luis did an excellent job on my bathroom. He had to do a lot of prep work before starting the tiling, including rebuilding the floor and repairing the walls. At every stage he explained what needed to be done, ensured that I wanted to go ahead, listed the materials that would be needed, and the cost. It made a huge different to me that Luis was willing to source and purchase all materials; he checked in with me from the suppliers as to choice and cost, and sent receipts for every penny. I cannot recommend him highly enough, for his knowledge and expertise, his honesty and hard work, and also for being such a lovely person, nothing is too much trouble. I am delighted with my new bathroom, and am planning more home improvements with Luis, when he is free again!
Home Renovations Ltd
Rating: 5 out of 5
Extension Builder in St James
We're a building company specializing in house extensions, loft conversions and refurbishments. Our clients come from New Malden, where we're based, but also surrounding areas. The vast industry experience enables us to provide valuable advice, professional services and individual approach, benefiting our customers. As we understand trust and credibility are crucial when undertaking such projects, we arrange viewings and provide customers with references and photos of our most recent projects.
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Latest review:
Extensions- 24 Jun 2017
We had a large piece of work done by Johan and his team. It was a 4m single storey rear extension with new kitchen installation, converting the old kitchen into a downstairs bathroom and utility room, plus other bits and bobs like new boiler, rear patio. We got quotes from a few builders, Home Renovations weren't the cheapest, they were actually towards the higher end. But we went and saw their previous work and spoke to some of their other clients. The work was done to a high quality and the clients seemed to be happy so we decided to go with them. Johan's team are very hard working, professional and polite. Pawel and his team of builders, bricklayers, plumbers, electricians, etc. would turn up before 8am and finish at 6pm working solidly throughout the day. There is Magda as the project manager who keeps you in the loop, and answers any of your questions (which we had many). There is Michaela on the finance side who keeps you up to date with the budget. Our budget went over by 5% with "variations" (extra work or materials) but it was always communicated why and the work wasn't done without our approval. Pawel would give his recommendations but the final word would always be ours. But these things can add up. Overall we were very happy with the build, it was done to a very high standard. They also finished it before time. They said it would take 12 weeks in fact they finished it in 10 weeks which was amazing as you would normally expect these things to go over.
Sort Project Management Limited
No reviews yet
Extension Builder in St James
Based in London Sort Project Management Ltd is a construction company with over 10 years experience. Since we established in 2010, we have built over 100 new homes, extensions and conversions. We specialise in refurbishments, constructing new homes, loft conversions and extensions for greater living spaces. We also offer a full-service residential Design and Build service. We also offer the following services: Landscaping & Gardening Garage & Garden Room/Summer House Construction Roofing
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Lusha construction ltd
No reviews yet
Extension Builder in St James
LUSHA CONSTRUCTION LTD A reliable and readily available who has been operating for the last 10 years. We pride ourselves in providing a professional, friendly, and high-quality service to fulfil the needs of our clients. These include: Ground work Refurbishment Remodelling Tile work installation Bathroom Fitters Bathroom design Bathroom refurbishment Bathroom renovation Carpentry Carpentry and Joinery Commercial builds Decorating Electrics Extensions Kitchen Fitting Landscaping Loft conversion Plastering Plumbing Rendering Restoration Underfloor Heating Fencing etc.. Our professional and friendly team members are happy to talk you through your needs and give you a free quote, so why not give us a call to get a free quote.
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Buildswell ltd
Rating: 5 out of 5
Extension Builder in St James
my name is sehaj the main contractor of buildswell ltd.We are a full facilities management and installation company,If you are thinking of renovating your home,building an extension, or changing your roof. Sehaj from buildswell has a local and trusted construction business to provide maintenance and building services of the highest standard at competitive prices. Very friendly and professional
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Latest review:
Extensions- 20 Jan 2021
Trusted person good quality extension with no delays
P R Henry
Rating: 5 out of 5
Extension Builder in St James
PR Henry Building Ltd. Member of Federation of Master Builders. 30 years of experience in the building industry with a strong commitment to meticulous attention to detail. Our forte lies in comprehensive property refurbishments and renovations, covering a wide array of services such as extensions, structural repairs, kitchen and bathroom refurbishments, plastering, rendering, brickwork, bespoke carpentry, painting and decorating. Please kindly refrain from considering us for shortlisting if your primary criterion is the lowest cost rather than quality.
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Latest review:
Plastering- 24 Nov 2020
Pat was absolutely fantastic he came over to quote very quickly, gave a fair price and the did the work quickly and to a very high standard. He also offered lots of other advice and went above and beyond. I would really recommend him for building work
SPEKT GROUP LTD
Rating: 4.8 out of 5
Extension Builder in St James
We are a team father and sons, with over 30 years of experience in Wood Occupations and construction sites, who's goal it's to provide our customers with quality services.
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Latest review:
Carpentry- 11 Mar 2025
Great work and would recommend!
10/ten construction ltd
Rating: 5 out of 5
Extension Builder in St James
Hi I am Landi, 33 years old, I’m in construction industry over 15 years. Build your future with us! We are constantly developing our skills and expanding the knowledge, so as to provide you with modern and effective services. Our team is always up-to-date with all the most important novelties in the field, what makes it possible for us to apply innovative techniques and use professional tools. Thanks to that, we can perform complete refurbishment perfectly. If you choose us to be your building contractors, you can be certain that every project will be precisely planned and carried out. 10/TEN CONSTRUCTION LTD
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Latest review:
Carpentry- 6 Dec 2024
We recently had Landi around to quote on a number of jobs we needed doing around our house. We booked him to fix our roof, which was leaking water - he and his team did an absolutely fantastic job. They were responsive, thorough and did a great job. We won't hesitate to recommend him to anyone and get him back for any work we need doing.

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.