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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Blueprint Builder UK
Rating: 4.4 out of 5
Extension Builder in St James
I’m a local builder with over 25 years of experience, specialising in high-quality brickwork and home extensions. From start to finish, I take pride in delivering reliable, professional service and strong attention to detail. Whether it’s a full extension, garden wall, or any kind of brickwork, every project is completed to the highest standard. Customer satisfaction and honest workmanship are at the heart of what I do.
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Latest review:
Conversions - General- 3 Apr 2026
I originally left Stuart a five star review because the workmanship and communication were excellent, and I booked him to return to complete the internal works on our extension. After paying a deposit, the work was due to start on 27 June, but Stuart never turned up and stopped communicating. His partner later asked if I could delay the work for a few months because he couldn't contact me. When I explained I couldn't wait and politely requested my deposit back, I was blocked. I have now been left with no option but to take him to the Small Claims Court to recover my money. It's a real shame because the original work was of a high standard, but I cannot recommend someone who takes a deposit, fails to return, and then ignores all communication.
LJS construction
Rating: 5 out of 5
Extension Builder in St James
Extensions, lofts, kitchens, refurbishment, driveways and patios
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Latest review:
Landscaping- 6 Jun 2023
We are so happy with our new patio and garden. They were on time, very helpful and did a fantastic job, for a very competitive price. We will definitely use LJS for any future projects.
Nick
Rating: 5 out of 5
Extension Builder in St James
With 14 years experience in construction I undertake all kind of jobs: built, repairing and maintaining. I'm a reliable and a good communication person. Delivering great results within the planned time frame and budget is at the basis of what we do. We work closely with our clients, providing advice, discussing alternatives and taking on responsibility for the execution of all activities. We arrange orders, deliveries and returns of materials.
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Latest review:
Carpentry- 26 May 2024
Nick is fantastic and a highly skilled professional. I am very happy with his work. He communicated very clearly. He understood what I wanted and the end result went above and beyond my expectations. I am so happy I’ve found him and definitely using him for future work!
A2Z Property Improvement Ltd
Rating: 4.9 out of 5
Extension Builder in St James
A well establish Building Contractor with 24years experience, Dealing with all kind of Home Extensions, Loft Conversions, basement conversion, out buildings, electrical wiring, plumbing & boiler fitting, tiling, kitchen and bathroom fitting, roofing, K rendering, property refurbishment and decorating
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Latest review:
Extensions- 10 Apr 2021
Although I posted for a kitchen extension quote I decided that I would proceed with this at a later date. I did have a lot of other building work such as chimney removal that was undertaken by A2Z Property Improvement Limited. I am happy with the the work that was carried out. I'll certainly be reaching out to A2Z again for the extension once I'm ready to proceed. I would definitely recommend this company.
Shelomack designs
No reviews yet
Extension Builder in St James
I used to watch while others built but i have spent 18 years doing what I used to pay others for. I am a very physical person and consider quality to be my aim. I holds a 127 iq score because of my quick and efficient way of creating the possibilities to satisfy and bring dreams to reality. I am located in Hackney of London where I grew up. My practical experience extends beyond building houses but also conversion of cars and using recyclables for design. I am very open minded and inventive. Ready to satisfy.
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London sky construction
No reviews yet
Extension Builder in St James
Dear customer I happy to introduce my self , I do all domestic and commercial construction job , new build , full refurbishment include electricity, plumbing, carpenter , flooring, decorating, tile work , roofing , gardening and structure job as well . Our objective to satisfy the need of the client to get the maximum benefits that he can get it from the project . Our quote is realistic and competitive price according to the market .
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FBF Construction Ltd
Rating: 5 out of 5
Extension Builder in St James
We take all types of jobs from demolish a house and rebuild at the highest standards.
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Latest review:
Florin extended and completely refurbished our 4-bedroom semi-detached house. This included extensive steelwork, underfloor heating, complete re-plumbing and rewiring, excavation, and an entirely new slate roof as well as varying extensions up to three floors high. I cannot say enough good things about his workmanship, professionalism and reliability. His workmanship makes a perfectionist like myself happy. He is also completely professional: even with our difficult neighbours he was always courteous and understanding, and even helped them sort out issues at a moment’s notice that had nothing to do with his building work on our property. And he is also thoroughly reliable. I cannot think of any instance where he committed to something and did not deliver — he even managed to finish all the work on our house ahead of schedule and on budget. We have been so happy with his work that we contracted him to build us a summer house as well, from scratch, and to complete revamping our front garden including elements of hard landscaping. Again he delivered flawlessly and we are very happy with the result. We also continually receive positive comments from people passing by and just seeing the front garden. We have used several other builders in the past on other properties, including far more expensive ones, and none compare to his level of competence, attention to detail in his workmanship, his complete professionalism and thorough reliability. Now that we have found Florin, we will never look for another builder again. I just hope once others experience what he delivers for themselves he will still have some availability for us in the future!
BWH Construction
No reviews yet
Extension Builder in St James
Hi my name is Brian, I have been working in the construction industry for over 20 years, in this time i have worked with various big companies on projects from the Channel tunnel, to demolishing houses digging basements then rebuilding. References available upon request
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JJPeachey Carpentry
No reviews yet
Extension Builder in St James
A qualified carpenter, competent in all aspects of carpentry. Site and residential work experienced. Happy to look at any types of work.
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Safe build contractors ltd
Rating: 5 out of 5
Extension Builder in St James
My name is Gezim and I have 10 years experience in the building trade working in a variety of jobs such as extensions, lofts, specialising in garden walls etc. I am a professional bricklayer with a handy and professional team behind me. I deliver exceptional, friendly, and fast service. I have good practical skills, with the ability to read plans, and work in a well organised and accurate way.
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Latest review:
Bricklaying- 25 Mar 2022
I found Gezim a very polite and well mannered person. He is very reliable with a professional approach to the tasks and a good listener.He build a new wall for me at my property. I am extremely happy with his works. He explained to me exactly what he was doing and why he has to do the job in such away which is very rare nowadays. I would recommends him 100% to anyone looking for building works.
Daniel
No reviews yet
Extension Builder in St James
👋 We are a small Italian family-run business based in North West London, specialising in tiling, kitchens and bathroom refurbishments. 🧱 With over 25 years of hands-on experience, we take pride in delivering precise, clean and long-lasting results. ✅ All our work is guaranteed and carried out with attention to detail and respect for your home. 📍 We cover West Hampstead, Kilburn, Camden, and surrounding areas. 📩 Feel free to request a quote – we respond quickly and are happy to visit for a free assessment.
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G.W.Builders
Rating: 5 out of 5
Extension Builder in St James
My name is Gavin. I have been a bricklayer since leaving school and have over 25 years experience in the building trade. Feel free to check my excellent feedback. Working area Sutton Coldfield and surrounding areas. Willing to travel further for bigger jobs. Free Quotes within a 5mile radius of Hardwick.
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Latest review:
Extensions- 20 Sep 2023
GW builders did an amazing job building my porch. Gavin and the team were friendly and professional throughout. Would definitely recommend to others and use again
Memaar Construction
Rating: 5 out of 5
Extension Builder in St James
Our Expertise MEMAAR Construction is a business specializing in refurbishment, renovation, extension, painting, flooring, decoration, tiling, and demolition services. With a commitment to quality craftsmanship and a customer-centric approach, MEMAAR emphasises personalised service and priorities client needs. The business is supported by an expert team in the construction industry and aims to use sustainable practices while offering affordable pricing without compromising quality. Refurbishment is about improving or refreshing existing structures without making major changes to the layout. It often involves repairs, repainting, replacing fixtures, or upgrading finishes to bring a building back to a good condition. For example: updating office interiors, repairing walls, replacing windows, or modernizing outdated spaces.
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Latest review:
Extensions- 16 Jul 2026
They did fantastic Job.
Plumb4All
Rating: 5 out of 5
Extension Builder in St James
With over 20 years’ experience in the plumbing and building industry, this has enabled our team at **Plumb4All** to become a well-known and trusted company. We offer a 24/7 call out service and long term support for existing clients as a single point of contact for any future queries and issues. Our many happy and repeat customers find us through word of mouth and being fully qualified gives you the peace of mind that quality of service and very high standards are at the core of our values.
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Latest review:
Bathroom Fitting- 7 Mar 2021
Very professional and very thorough Solved the problem efficiently Would definitely recommend.
BOTNARI CONSTRUCTION
Rating: 4.4 out of 5
Extension Builder in St James
We at BOTNARI CONSTRUCTION provide a service of maximum quality and client satisfaction . Having over 25 years experience in the field we have completed jobs big and small to the best standard .
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Latest review:
Electrical- 26 Jul 2026
Genuinely one of the worst builders we have come across. David rewired the flat and Stefan plastered the hallway. David is NOT qualified as an electrician and cut corners wherever he could. David leveraged us for money mid job and in the end left the job without finishing and without providing a certificate. David ran cables behind door frames (awful idea), got the cheapest material, forgot where holes were for spotlights and switches among many issues which meant we had to constantly ask our builders to fill the holes and make good. Stefan did the hallway plastering without putting on mesh. The plaster cracked within 2 weeks and the paint keeps cracking and will be a constant problem. When asked to come back and fix the issue - he point blank refused. They were the cheapest quote but we really hope we had gone to someone else
Handy Man - Radek help you
Rating: 4.7 out of 5
Extension Builder in St James
There is always something that needs doing!
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Latest review:
Restoration & Refurbishment- 17 Oct 2019
Radek is a friendly hardworking young tradesman,he turned as he agreed and completed the various jobs I originally asked him to do, my wife & I were so p[eased with his work we asked him to build an extension garden room for us.he has nearly finished that and we are very pleased not just with the quality but also the cost.we would not hesitate in using him again or recommending him to others.

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.