Extension Builders in St James

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.4 (19 reviews)

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Some of our top rated extension builders in St James

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AIA BUILDING CONTRACTORS LTD
Rating: 5 out of 5
Extension Builder in St James
Our Family run business is built purely on word of mouth and on our reputation with genuine authenticated reviews available on our website. we take pride in all aspects of our work from home improvements inside and out, Bathroom Refurbishment, New Roofs, Painting and Decorating, Loft Conversion, Rear Extension, Velux windows, Roof Repair, Gutters and Drain pipes unbloking
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Latest review:
Bathroom Fitting- 25 Mar 2022
Fantastic job very pleased with my bathroom under the stair. Thank you Ben. Pamela Robinson
D.S builders
Rating: 5 out of 5
Extension Builder in St James
Hi there I am a reliable tradesman and pay etention to detail. Been in the building industry for over 20 years.
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Latest review:
Tiling- 19 Apr 2023
Steve was very helpful and worked quickly to get the job done He is very knowledgeable and also completed another job for me I would definitely recommend him He helped me choose products and collected materials I needed Very glad I chose him to complete the work
GRANEROS IMPROVEMENTS LTD
Rating: 5 out of 5
Extension Builder in St James
Responsibility
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Latest review:
Carpentry- 21 Mar 2026
Adi has performed an excellent job, repairing couple of garden fences, very satisfied with his work and the way he has handled the job!
DK Home Refurbishment
Rating: 5 out of 5
Extension Builder in St James
Turn your property into the home you’ve always wanted — with DK Home Refurbishment Ltd. With over 25 years of experience, we specialise in loft conversions, house extensions, basements, full refurbishments, and property maintenance across London. We provide a complete end-to-end service, including: ✔ Architectural design & planning support ✔ Council applications & approvals ✔ Structural engineering ✔ Building control compliance ✔ High-quality finishes and attention to detail We take pride in reliable workmanship, clear communication, and high standards on every project — from concept to completion. 📩 Message us today to discuss your project and get a free quote. #LoftConversion #HouseExtension #FullRefurbishment #PropertyMaintenance #LondonRefurbishment
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Latest review:
Joinery & Cabinet Making- 13 Apr 2015
Daniel was excellent, incredibly friendly and happy to talk through various solutions for our problem and also helped with an unrelated issue we had. Can't recommend highly enough, thanks Daniel
Musawir Architecture Limited
Rating: 5 out of 5
Extension Builder in St James
We are fully qualified & established architectural design team, with high success rates in obtaining residential and commercial planning approval. A multi-disciplinary consultancy with 10 years combined experience. We provide services for all projects, new builds, extensions, conversion along with commercial projects and change of use. Musawir Architecture retains our competitive edge having exceptional approval rates for planning & building regulations submissions and offer outstanding quality.
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Latest review:
Extensions- 5 Feb 2021
Abul was very professional and went through our extension plans thoroughly, making sure he understood exactly what it was we were after and made some suggestions himself. He has been very easy to contact with any queries, a great service.
AVmen
Rating: 5 out of 5
Extension Builder in St James
We are AVmen Construction We provide a range of Design and Build services to Luxury Commercial & High-End Residential properties in a professionally estimated, planned, and controlled manner: Bathroom Design, Reconfiguration, Refurbishment/Renovation 2D/3D CAD drawings and services for complex refurbishments Extensions, Conversions, Modernisation from the scratch Kitchen Extensions and Complete Kitchen renovations Building Shell & Core, Mechanical, and Electrical Services.
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Latest review:
Carpentry- 7 Sep 2020
Amiran delivered an excellent job. The sauna was supplied devoid of full clear instructions and materials and Amiran was able to solve all the issues in a timely and satisfactory manner. Very good workmanship, attention to detail and create problem solving. Would hire again.
REALTOP LTD
Rating: 5 out of 5
Extension Builder in St James
Good morning, Realtop Ltd provides commercial and domestic full refurbishment services, helping clients bring their dream spaces to life through our experienced and professional team. Our services include painting and decorating, interior design support, bespoke fitted solutions, flooring installation, white walling, composite and hygienic cladding, door installation, and general refurbishment works. Please note that being shortlisted causes us to pay a lead fee, so kindly shortlist us only if the estimated cost I have offered is suitable for your budget.
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Latest review:
Hard Flooring- 21 Jun 2025
Brilliant job done by Vincento . Right from the first visit to the job completion very professional and done the job rightly . Will definitely recommend. Five stars.
creative solutions 4 you limited
Rating: 5 out of 5
Extension Builder in St James
a small building and restoration company, a builder with over 20 years of experience, we take proud of our projects building a good relationship with our clients.
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Latest review:
Bathroom Fitting- 10 Nov 2020
William and his team were very good and installed an entirely new shower cubicle in place on an existing cupboard in a bathroom with previously only a WC and sink. I am delighted with the result and will be using William and his team again for other projects across my rental portfolio.
Victoria Urban Contractors LTD
Rating: 5 out of 5
Extension Builder in St James
we pride ourselves on being builders and contractors that are synonymous with high-quality, skilled craftsmanship. We provide a full range of building services in London, from renovation to restoration and site management. No matter how big or small your project is, our approach is always the same – focused, professional and with true attention to detail.
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Latest review:
Extensions- 18 Sep 2024
I looked at 5 quotes and was so happy to have chosen Elvis and his highly experienced team. They did an excellent job of building a new 11sq meter garden rear extension. This was a bit complicated project because it’s a listed house. Elvis and his team were hardworking, always responsive and came up with great solutions when necessary. I am very pleased with the high quality end result. I would use them again and can't recommend them enough! Great job done
Constructum Code Ltd
Rating: 4.2 out of 5
Extension Builder in St James
****** Constructum Code building company ****** We offer various construction services, from fence building to renovation work, extensions, home building and loft conversions. We also provide a wide range of interior building and renovation services. We have highly qualified project managers with over 22 years of experience in construction & building industry. WE OFFER: *The Complete Service* *10 Year Guarantee* *Free Estimates* *Competitive Prices* *Full Building Control Approved Installer* *Excellent Designs and Unbeatable Workmanship* *Fully insured building service* Constructum Code, at its core, is a construction company through and through. We are general contractors who can provide a wide range of building services, both small and large. Services Provided: 3D Rendering, Basement Conversion, Building Design, Complete Bathroom Renovation, Complete Kitchen Renovation, Conservatory Design & Installation, Custom Build Homes, Home Renovation, House Extensions, House Plans, House Restoration, Interior Architecture, Interior Design, Loft Conversion, Loft Restoration, New Home Build, Project Management, Balcony Design & Construction, Concrete Construction, Concrete Repair
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Latest review:
I ordered repairs from the Constructum Code company, I wanted to create a play area. The guys tried to select all the materials and work technologies to suit my budget. The tiles on the walls and floor were laid well. The work was completed efficiently and on time. I recommend this company...
We Fix Your House Ltd
Rating: 5 out of 5
Extension Builder in St James
We Fix Your House is a family-run, small team of experienced industry specialists with many happy clients in and around London. We take pride in our work and ensure that our customers are always happy. So whether you're are looking for a little DIY help, or a complete renovation of your property, we're happy to help. You'll be pleasantly surprised by our competitive prices too, and YES, we can work around your budget.
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Latest review:
Plastering- 28 Apr 2019
Great job, very professional
All Aspects Group Ltd
Rating: 5 out of 5
Extension Builder in St James
All Aspects Construction is a multi-disciplinary contractor who specialise in the construction, refurbishment and maintenance of commercial and domestic buildings. We focus on delivering the very best craftsmanship in all services delivered and a quality end product through sustainable construction all within an approachable and professional manner.
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Latest review:
Painting & Decorating- 30 Apr 2019
Thoroughly recommend this Company, very professional, industrious, thorough, and exceptionally helpful, left the working areas clean and tidy, definitely value for money, delighted with the job of work carried out.
S.k Building & Decorating Services
Rating: 5 out of 5
Extension Builder in St James
S.K Building & Decorating Services Ltd is a London-based building company specialising in a diverse range of construction services. With a focus on delivering high-quality results, the company excels in Extension building, Property refurbishment, Bathroom installation and Kitchen installation. Renowned for their expertise and commitment to customer satisfaction, S.K Building & Decorating Services Ltd has established itself as a reliable choice for clients seeking professional construction solutions in the London area. Whether it’s expanding living spaces through extensions, revitalising properties with refurbishment, or creating functional and stylish kitchens and bathrooms, S.K Building & Decorating Services Ltd stands out as a reliable partner in the construction and renovation industry. Get in contact now for a free no obligation quote!
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Latest review:
Restoration & Refurbishment- 7 Apr 2025
Senad and his team did a great job. They completed the project quickly and left the flat and common parts clean and tidy. Really happy with their work and would recommend. Hope to use them again.
30 Day Extensions Ltd
Rating: 4.8 out of 5
Extension Builder in St James
COMPLETED 130 projects since lockdown•WIMBLEDON & SURBITON SHOPS now open. FREE- architectural and design services if you use us. •Fantastic reputation, reviews on google and webpage. • Speed, we build shell in 30 days. •priced by a QS and we add 15%. Simple! • •Highly skilled reputable teams. • Guarantees that mean something. • Peter snelson, the CEO has over 40 years experience in the industry internationally and nationally. A member of The Federation of Master Builders.
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Latest review:
Extensions- 30 Nov 2020
A really excellent set up of builders. Peter was great in evaluating the work and what we needed done. Sue was clear in her communication on costs, and then execution of the works by Taras and his team was superb. The extension was built in fantastic time-frame, and the end result is great. The work-ethic of the builders is what really makes them so good. They are on-time every day, and relentless with working hard each day.
Jt building
Rating: 5 out of 5
Extension Builder in St James
I have been a multi trader for over 12 years, with quite extensive experience working in majority of trade departments from kitchens, bathrooms, tiling, plumbing, doors, windows, joinery, carptentry, first fix, second fix, lofts and extensions, have seen through many projects and worked with many people. Can also assist with design ideas/plans as well as build. Happy working with small or large projects, take full responsibility and pride in my work.
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Latest review:
I couldn’t be happier with the work carried out on my home. The tiling on the ground floor, the laminate flooring upstairs, and the kitchen units were all completed to an exceptionally high standard. The attention to detail was outstanding, and everything was finished neatly and professionally. He was reliable, hardworking, and clearly takes great pride in his work. The end result looks amazing and has completely transformed my home. I would highly recommend him to anyone looking for quality workmanship.
REA Construction LTD
Rating: 5 out of 5
Extension Builder in St James
The company’s success is built on the strong belief of quality work, attention to detail and on-time completion. Rea Construction Ltd has an in house team of builders, architects, and interior designers with all the relevant skills and qualifications which enable us to offer a fully comprehensive design and build service. Get in touch today for a free on site consultation.
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Latest review:
Extensions- 8 Dec 2017
We couldn’t be happier with the professionalism and quality of workmanship from REA Construction. The project was delivered within budget and on time. We lived in the property during the work and we, our neighbours and the site were always treated with the utmost consideration. There were almost no hitches and, when they did occur, they were dealt with immediately and thoroughly. Our project team, led by Kristjan and Besi, were universally hardworking, organised and produced work to an excellent standard. Communication is great, the people are wonderful. Renato was someone I felt I could trust from the moment I met him and he never let us down. He and everyone at REA genuinely care about what they do and that their customers have a happy experience. We certainly did and would have no hesitation recommending them to others.

4.4

Top rated Extension Builders

Our Extension Builders in St James, are rated 4.4 out of 5 based on 19 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.