Extension builders in St James

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.6 (22 reviews)

Easily find verified St James Extension Builders. Just post your job to get quotes from MyBuilder's Extension Builders in St James.

Select a service

How it works

Post your job for free

Tell us about your job, and we’ll alert suitable tradespeople in your area. It’s simple and free.

Tradespeople respond

Once your job is posted, you’ll get responses from interested tradespeople through the website.

Review profiles and choose

Browse profiles, work history, and feedback, then choose who you wish to share your details with.

Some of our top rated extension builders in St James

3760 Results

Sort by:

Arka Developments
No reviews yet
Extension Builder in St James
Arka Developments is a London-based design and build company specialising in residential and commercial refurbishment, house extensions, and new build projects across North West London. With a background in architecture and construction project management, we deliver well-planned, high-quality projects with a strong focus on design, cost control, and efficient execution. We offer a fully integrated service from planning and design through to construction ensuring a smooth, transparent process and consistent results. Whether you’re upgrading your home, extending your space, or delivering a development project, Arka Developments provides reliable, hands-on delivery at every stage.
Get in touch
M & G Home Improvement
Rating: 5 out of 5
Extension Builder in St James
With over 12 years of experience in the construction industry and an admirable track record, M&G Home Improvement can have confidence in providing remarkable levels of competence and expertise from new-builds to all refurbishment projects. We are very well recognised within the construction industry for our broad-mindedness, honesty and accuracy in our work. We recognise the needs of our clients and our devoted team that can accomplish even the most complicated challenges with confidence.
Get in touch
Latest review:
Extensions- 4 Jun 2021
We needed a kitchen extension, and after getting 10 quotes from local builders, M & G were extremely competitive on price. The whole process was made simple, mainly due to the knowledge and communication from Miri and his team. Before I chose M & G, I was invited to see other jobs they were working on and after seeing the first extension, my mind was made up. Miri and his team are Punctual, Tidy, Knowledgeable, Professional, Hardworking and I cant recommend them high enough. I will be hiring Miri and the team for our Loft conversion soon.
paul king
Rating: 5 out of 5
Extension Builder in St James
With 20 years experience of quality through excellence has established our company as one of the leading providers of building services in the London area We specialise in home extensions, damp proofing , interior and exterior refurbishment for the modern and traditional home. we know our client focused culture, our commitment to quality services and our passionate approach to execution of works is a proven formula which gets the best results.
Get in touch
Latest review:
My partner and I are so pleased with the extension work which Paul & team carried out, not just what was done but also the way it was done. All of the team were great - they turned up when they said they would, and simply got on with their work, They were all polite, friendly, helpful, conscientious, and made several suggestions to improve the finished work. They frequently checked on details with us as the work progressed to ensure that we was satisfied and our needs were met, we was extremely impressed with how they understood & handled our neighbours, will definitely use again in future projects!
Cocis Construction Group
Rating: 5 out of 5
Extension Builder in St James
Cocis Construction Group LTD is a family-run construction company with over 25 years of hands-on experience in the trades. We specialise in home renovations, extensions, bathroom and kitchen refurbishments, and property development across London. As a young, ambitious company, we combine traditional craftsmanship with fresh ideas and modern techniques to deliver projects efficiently and to the highest standards. Our team takes pride in attention to detail, clear communication, and building lasting relationships with homeowners, landlords, and property investors alike. At CCG, we don’t just build structures—we bring visions to life, turning ideas into beautifully finished spaces. Contact us today for a free quote and see how our expertise and dedication can make your next project a success.
Get in touch
Latest review:
Cocis Construction Group done the full interior painting of our 5 bedroom house and we are really happy with the result. The team was polite and worked very hard every day. They kept things clean and finished everything on time like they said they would. The paint finish looks great and the whole house feels fresh again. Would definitely recommend them if you need painting done.
Kuci max construction ltd
Rating: 5 out of 5
Extension Builder in St James
Kuci Max Construction Ltd. brings over 15 years of experience in the building industry, specialising in residential and commercial construction and renovation. Our services include, extensions, driveways, brickwork, garden & design, tiling, refurbishments, kitchen and bathroom installations, and landscaping. We are committed to delivering high-quality, customer-focused solutions with transparent pricing and full accountability. Our experienced team is dedicated to transforming spaces and bringing your vision to life. For review you can check on my website: KUCIMAXCONSTRUCTIONLTD on google!!
Get in touch
Latest review:
Stonemasonry- 22 Dec 2024
Neatly finished job. Very cooperative team!
anova design ltd
No reviews yet
Extension Builder in St James
Full scale extensions, lofts, refurbishments and new builds. Qualified and experienced tradespeople, design services.
Get in touch
Antonio Abreu
No reviews yet
Extension Builder in St James
I have been working in construction for 20 years. I first started as a Carpenter did my NVQ Level 2 then worked for a company fitting kitchens and bathrooms for 2 years. After that started working on my own and then build a small team. We now specialise in lofts, extensions, full house refurbishment, kitchen fitting bathroom fitting and decorating. We are very professional, very easy to work with, and have loads of excelent references.
Get in touch
PRO-TECH BUILDING SOLUTIONS LTD
No reviews yet
Extension Builder in St James
PRO-TECH Building Solutions LTD undertakes a wide variety of refurbishment and renovation services. We provide a range of construction and renovation services in London area. We are renovation contractor specializing in residential refurbishment, building construction and internal reconfiguration services. We guarantee you'll be extremely satisfied with the result. With decades of experience in building, our skilled team has the know-how to create your perfect home. We offer a wide range of services to meet every type of projects. Book an appointment at a time to suit you and we will look at your refurbishment requirement and provide a free no obligation quotation
Get in touch
Eloah Israel security and construction Ltd
Rating: 5 out of 5
Extension Builder in St James
Hi, we are a company that prides itself on providing good work to our customers, making their dreams come true! we guarantee complete satisfaction and quality in carrying out our work, respecting the delivery times determined by our customers
Get in touch
Latest review:
Erick demonstrates remarkable thoroughness, reliability, and trustworthiness. His keen attention to detail is exceptional, and he leads a highly efficient team that promptly meets all demands and tasks. He successfully refurbished my entire house in Northampton, adhering to the projected timeline without any delays or setbacks. Throughout the project, he never dismissed any of my requests and fulfilled them all effortlessly. Erick is always easily accessible, promptly responding to calls and messages. I have enthusiastically recommended him to several of my friends, all of whom are immensely satisfied and grateful for his services. Furthermore, his pricing is fair and reasonable, leaving me extremely pleased with the quality of his work.
Shalva Simonishvili
No reviews yet
Extension Builder in St James
I have over 10 years of experience in the construction industry, having completed a wide range of projects, from residential homes to commercial buildings. I am based in the Canada Water area and am available to work across London and surrounding areas. I specialise in bricklaying, blockwork, and delivering high-quality finishes. I take pride in my attention to detail, reliability, and honest communication. I am committed to delivering high-quality workmanship, completing every job on time, and ensuring my customers are satisfied with the final result.
Get in touch
Co.35 Limited
New on MyBuilder
Extension Builder in St James
CO.35 | Design-led Renovation & Refurbishment CO.35 is a London-based design and refurbishment company helping homeowners improve, renovate and transform their properties. Combining professional backgrounds in interior architecture, civil engineering and construction project management, with experience dating back to 2019, we offer a practical, design-led approach to residential refurbishment. Our services range from individual room improvements and kitchen and bathroom renovations to comprehensive property refurbishments, covering everything from initial planning and design development to construction, specialist trades and finishing works. Based in North London, we undertake projects across Greater London, bringing design understanding and technical expertise together throughout the process. We believe a successful renovation should be thoughtfully designed, carefully executed and clearly communicated. Whether you're updating a single room or refurbishing an entire property, our aim is to deliver a result that works beautifully and practically for your home. Design • Deliver • Maintain
Get in touch
Leon building contractors limited
Rating: 5 out of 5
Extension Builder in St James
Hi.Welcome to our profile. We are well established building company working in London and surrounding areas. We are specialists in loft conversion and extension. All kind of building works undertaken.also happy to provide photographs and references of our previous happy customers.We offer free quotes.Fully insured,skilled trades men. Finish projects on time limit to suits you. We are proud member of Association of Master Tradesmen and check a trade. thanks for visiting our page.
Get in touch
Latest review:
Extensions- 25 Apr 2025
we recently had the pleasure of working with Leon building contractors limited, and i cant recommend them highly enough! They carried out a single story rear extension, an internal garage conversion and porch to the front of the house. On top of that they installed our new kitchen and toilet suite downstairs all finished to a high standard. From start to finish Vic and his team were amazing nothing was too much trouble and were always happy to do anything without a fuss. Their attention to detail was first class. It wasn't only us who was impressed but our neighbors commented how friendly, respectful and hard working they all were and have already asked for his contact details. Vic trade contacts also helped us with windows/bi-folds and quartz worktops all high quality at much cheaper prices i could find myself! Thanks again to Vic and the team for doing such a brilliant job, we have no hesitation to use again in the future!
BRANDON RENOVATION
No reviews yet
Extension Builder in St James
Quality is our hallmark with warranty
Get in touch
AN Imperial Build
New on MyBuilder
Extension Builder in St James
We are a professional construction and refurbishment company providing high-quality services across London. We specialise in full property refurbishments, including painting and decorating, flooring, drylining, carpentry, tiling, kitchen and bathroom works, and general repairs. We pride ourselves on reliability, attention to detail and delivering every project to a high standard. No job is too small, and we are always happy to discuss our customers’ requirements and provide a professional solution.
Get in touch
BSD Design & Build LTD
No reviews yet
Extension Builder in St James
🏗️ Build with Confidence – Build with Us! 🏡 B.S.D Design & Build is a proud member of FMB. Not every builder is a Master Builder! In an unlicensed industry, choosing a Federation of Master Builders member gives you peace of mind, knowing we meet strict entry criteria and undergo continuous monitoring. ✅ Expert Craftsmanship ✅ On-Time & On-Budget ✅ Built to Last Trust the professionals. Contact B.S.D Design & Build today! 📞🔨
Get in touch
Civiltech
No reviews yet
Extension Builder in St James
We pride ourselves for delivering work collaboratively to a high standard, in the agreed time frame and budget with full transparency and safely.
Get in touch

4.6

Top rated Extension Builders

Our Extension Builders in St James, are rated 4.6 out of 5 based on 22 reviews from customers like you.

Quality screening

Easily find verified local tradespeople. Just post your job to get quotes from tradespeople near you across the UK.

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.