Extension Builders in St James

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.2 (19 reviews)

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Some of our top rated extension builders in St James

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Alexis Vedere
Rating: 4.6 out of 5
Extension Builder in St James
+20years experience in high end work. Very creative and open to uncommon projects.
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Latest review:
Handyman- 26 Oct 2025
Excellent tradesman, competent with amazing skills, professional,trustworthy and honest.
Belgravia Property Solutions Limited
Rating: 5 out of 5
Extension Builder in St James
Belgravia Solutions is a trusted provider of professional handyman and building services, based in Belgravia. We specialise in a wide range of trade services, including painting and decorating, carpentry, bathroom and kitchen refurbishments and most skilled work needed in a home or office. Our mission is to make your life easier by delivering high-quality work on time and within budget. With an experienced team and a commitment to customer satisfaction, we’re here to help with projects and works of any size.
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Latest review:
Had an emergency when a pipe burst in the flat above causing flooding damage. Struggled to find a responsive option when I luckily game across Belgravia Property Solutions. They promptly inspected my flat, got me an estimate, and executed the works with a multidisciplinary team - walls plastered and painted, electrical repaired, floor recarpeted. Works were finished within one week of the first phone call. BPS will be my first call next time.
Bespoke heating and cooling
Rating: 4.5 out of 5
Extension Builder in St James
Hello my name is Robbie, I am a qualified plumber and heating engineer, that’s also trained in electrics. I enjoy working out problems and helping customers come to the best resolution to their problems.
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Latest review:
Plumbing- 11 Apr 2026
Had my bathroom plumbing changed they did a very good job very happy with the results would recommend
FM Building
Rating: 4.8 out of 5
Extension Builder in St James
Honest and friendly company, we here at FM Building focus on complete customer satisfaction and make a promise to our clients to offer best quality services at competitive rates. All projects considered and dealt with in a professional manner regardless of the size or duration.
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Latest review:
Handyman- 12 Oct 2018
The flat was left in a very bad state after the tenants left. Marius was able to undertake all the jobs, from changing carpets, redecorate, repairs and clean up. Also gave good advice as I was not able to attend the site in person so Marius kept me updated with photos. The price was also good. Thank you. Will use these guys again.
WHG Consultancy Ltd
Rating: 5 out of 5
Extension Builder in St James
Award winning builders in South West and Central London. We offer a complete range of design and build services for residential and commercial customers include new build developments, renovations, refurbishments, reconfigurations, extensions, bathroom and kitchen fitting, as well as bespoke carpentry, joinery and electrical work. We think your property is as individual as you are and help you to achieve your ideal home through our highly skilled & experienced team of designers and builders.
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Latest review:
Restoration & Refurbishment- 28 Dec 2015
I did quite a bit of research before choosing Battersea Builders. They didn’t come in with the cheapest quote but I never base my choice on price alone. And it wasn’t miles above the other quotes I got. Instead, I chose them because they ticked a lot of boxes including a) good independent reviews, b) a dedicated PM, c) qualifications, d) quick responses, e) a decent website etc. Overall, they did a fantastic job. The quality of the work and finish is really good. The PM, Tommy, was really helpful throughout and the team was very polite and conscientious. They were also on site every day as promised and didn’t play that old builders trick of getting the job and then going offsite to secure another job elsewhere (resulting in the deadline being missed). Was it perfect? No, but then not many projects are. I have a few minor comments including the fact there was a misunderstanding about the quality of bathroom cupboard I needed so the original quote was insufficient and costs had to be increased half way through the project. Despite this issue, Tommy did his best to keep the extra costs down. One other niggle was that I asked them to keep all the manuals and instructions for all the fittings but they threw them out. Not a big deal but quite annoying. Overall, it wasn’t cheap but I would use them again because the work was done to a high standard and the team were a pleasure to work with.
Ifa construction ltd
Rating: 5 out of 5
Extension Builder in St James
House extension, lofts conversion, house refurbished, and new build
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Latest review:
Restoration & Refurbishment- 2 Jul 2023
AJ was thorough, friendly and thought things through. I would recommend him.
E Building Services
Rating: 4.7 out of 5
Extension Builder in St James
Hi Everyone 👋 Please Note: I am New with "My Builder" but I am a very experienced, and on my other websites I have many ratings and all 5 🌟 🌟 🌟 🌟 🌟 I hope I will have the chance to show you what I can do I have a range of experience across the trade, with specialised expertise in the following areas,over 12 years: -in Drylining -in Carpentry - in refurbishing restaurants and houses. -Bathroom renovation -Loft Conversions -House extensions After all that I finally have the team wich we can do jobs form A to Z -Plumbing (gas safe certified) -Electrical (Certified) -Roofs -Groundwork -Gardening -Fencing -Waste removal I'm happy to help across all jobs and answer any questions. Thanks for passing by and I hope to hear from you soon 😊🙏
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Latest review:
Carpentry- 30 Aug 2025
This builder expects you to be able to list every single part of the job that needs doing. If it's not communicated through messaging that you need something doing as part of the job then he won't do it. For example - the partition wall that was put up, was not filled because he said that was not communicated in the messages. I would not know everything that should be done in order for a partition wall to look half completed. It is perfectly clear that this is a common occurrence as he repeatedly mentioned how he always shows people the messages sent back and fourth as proof of what they asked for. Bottom line - if you don't know all the tiny steps included in the job you want done then be expected to not get a full job done. He took off £100 off the agreed price due to my disbelief and disgust but this did not help as I then had to find another builder to complete what should have been completed. How can any builder put up a partition wall and not fill where plaster boards are joined
2AM Construction
Rating: 4.6 out of 5
Extension Builder in St James
Hi this is Ali I am electrical contractors with over 10 years of experience who covers all types of electrical work. I do both domestic and commercial installations, rewiring, fault finding, repairing, fire alarms, smoke alarms, emergency lighting, EICR Certificate
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Latest review:
Electrical- 3 Oct 2025
went very well - almost superb, maybe of 5 stars 4.9.
fedora and sons
Rating: 4.4 out of 5
Extension Builder in St James
I have started working for myself in Europe for 10 years, came over to England with my family and have been working here for 11 years getting business from word of mouth. In my business I manage lots of sub contractors covering a wide range of trades which I have experience in too.
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Latest review:
Painting & Decorating- 24 Feb 2020
Quite literally the worst tradesman I have ever worked within 25 years as a property developer! He came and quoted to paint my house (a good price I must say), little did I know that this meant he would spray everything that he can see, not prepare the surfaces by sanding them down or protects things. This included door handles, hinges, radiators, alarms sensors, tiles and my own furniture and cooking utensils. First time I confronted him about this he said that we would clean everything, and we agreed to carry own. However, it became apparent that we was doing the same as previously discussed. have paid hi 66% of what was agreed, I quickly realised that the damaged he has caused was going to cost me far more and I told him to leave. The next day he turned up at my house with his wife demanding the balance which I refused to give him, they were both shouting outside my house, threatening to call the police. I eventually agreed to pay the 50% of what was left, just so that they would leave. However, even once he had confirmed writing his acceptance of this, he walks over to me and threatened me one final time, saying that he will take me to court etc, there is god and he will see to me! I advise to stay away from this person, better to pay a little more and work with professionals who don't agree with one thing and do another. He paints using a spray, which means you can not touch anything up and he quite literally paints everything he sees!!
Kalafuldeco
Rating: 5 out of 5
Extension Builder in St James
❌ We Turn Houses Into Kalaful Homes ❌ 350+ REVIEWS / 5 STAR RATING X⭕️X - WE'LL MATCH ANY REASONABLE QUOTES - X⭕️X Hi, This is Cristina in The Office. We Specialise in Flooring / Painting Int / Ext Building Services - Kitchens / Bathrooms / Lofts / Extensions.etc +£25 Each - Plane / Trimming Doors if required +Removal £50 - £75 Each Room + Disposal £100 - £300 If Required FLOORING ESTIMATES / WE ALSO DO PAINTING Fitting Beading / Scotia is Free, Inc in the Job Fitting Skirting is Min £200+ / Hallway Min £250+ Kitchen / Bathroom Min £200+ Laminate / Lvt Click ( Sub Floor Must be Reasonablly Level ) Straight Runs - £20m2 / Inc Hallways £25m2+ MIN £100 UPTO 5m2 Engineered Click Straight Runs - £25m2 / Inc Hallways £30m2+ MIN £150 UPTO 5m2 Hardwood T&G / Tongue & Groove Straight Runs - £30m2 / Inc Hallways £35m2+ MIN £200 UPTO 5m2 Herringbone - £40 - £45m2+ Cash Deals + 20% on Bank Transfer or if Invoice is Required - Payments To be Made End Of Each Day ❌ Must be Able to Provide Off Street Parking / Permits as The Crew Needs Access to The Vehicle at all Times. Thanking you in Advance Christina & Kam @ Kalaful Deco PAINTING ESTIMATES PAINTING ONLY - NO WALLPAPERING We also do Flooring / Gardening / Man & Van + Handyman Jobs Single Room - £300 Inc Minor Filling & Sanding / All White ) + £75 / 2 Colours / Woodwork £50+ £150 Extra To Paint on Fresh Plaster Living / Double Room - £400 Inc Minor Filling & Sanding / All White + £75 / 2 Colours / Woodwork £50+ Hallways- £450 - £750 Inc Working around 4-8 Doors Thanking you in Advance Christina & Kam @ Kalaful Deco
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Latest review:
Hard Flooring- 11 May 2026
Kalafuldeco has installed some wooden floor in my laundry room, great communication and nice job 👍
Done By Tom Ltd
Rating: 5 out of 5
Extension Builder in St James
Welcome to Done by Tom – we offer a completely bespoke design and build service for the London private sector. If you’re looking for clever, stunning and energy-efficient construction as well as interior design, we are it. At Done by Tom, we’ve come up with a unique success formula when it comes to memorable design and construction: combining the interior design, architecture and construction process into one seamless dream to deliver according to our clients vision.
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Latest review:
Fireplaces & Flues- 13 Nov 2017
i was so so happy with the service completed by done by tom. I had a really urgent last minute job and they were able to complete all the work to a really high standard and with a great price. I would trust them to do any building work in my house and am happy to have found a trusted builder for future works. Would recommend to anyone
My Home Services London Ltd
Rating: 5 out of 5
Extension Builder in St James
My Home Services London Ltd is a professional construction and home improvement company specialising in bathroom and kitchen renovations, house extensions, loft conversions, and full property refurbishments. We also provide expert gas, electrical, electronics, and smart home (domotics) installation and maintenance services. Our team delivers complete, high-quality solutions designed to transform homes by combining functionality, comfort, style, and modern technology. From small upgrades to large-scale renovation and extension projects, we work with a safe, reliable, and professional approach tailored to each client’s needs and vision.
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Latest review:
Handyman- 29 May 2026
Absolutely fantastic service, they did a great job!!! Friendly and professional. I look forward to having them back for more jobs. 100% highly recommend!! Thank you very much!
Ion Soceanu Construction Ltd
Rating: 5 out of 5
Extension Builder in St James
My company offering high quality all-in-one building and home renovation services to customers. Our Services Include : Restoration & Refurbishment Carpentry Painting Decorating Flooring Electrical Plumbing Plastering Tiling Roofing Extensions Loft conversion.
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Latest review:
Joinery & Cabinet Making- 24 May 2025
The work done exceeded our expectations...we decided to build more bespoke carpentry with Mini and team which we did not originally planned for
Extension Kings Ltd
Rating: 5 out of 5
Extension Builder in St James
I've been working in building trade for over 20 years , I can undertake any job small and big from foundations to the roof and anything between. I can provide any references and I have insurance of £5 million. Me and my team take pride at what we do and we do it first time right .our work is second to none , and proof of that is that you don’t pay anything upfront till you are fully satisfied with the quality.
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Latest review:
Extensions- 8 Oct 2018
Alban completed a lateral kitchen extension for me in west London. Very happy with the results and to add my name to others that have given 100% positive feedback. What I particularly liked - (1) Alban took great care to protect the rest of my house while working (protection, covers etc), (2) his team were friendly and polite to neighbours. Building works are always noisy and disruptive, they kept others 'on side' and (3) they worked to the timing and schedule agreed (4) they cleaned up, every single day (5) they worked to a high standard and corrected for any issues, despite my inevitable last minute changes. Wish him and team best success... happy to recommend. Rob
ResidentDevelopments
Rating: 5 out of 5
Extension Builder in St James
Conceiving and delivering aspirational residences, for the Resident.
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Latest review:
We have previously been burnt working with self proclaimed tradesmen. The organisation is professional and customer focussed. Working with them was a pleasure, I couldn’t recommend them enough.
MM
Rating: 5 out of 5
Extension Builder in St James
We are a highly experienced kitchen and bathroom design and installation company with over 20 years of proven expertise in delivering exceptional results. We provide a comprehensive, end-to-end service—from detailed consultation and bespoke design through to precise, high-quality installation—or a dedicated installation service tailored to your specific needs. Our work is defined by technical accuracy, refined craftsmanship, and a deep understanding of both aesthetics and functionality. We deliver bespoke kitchen and bathroom solutions across a full spectrum, from well-specified standard projects to luxury, high-end installations, all executed with exacting standards and attention to detail. Operating throughout London and the surrounding areas, we are committed to delivering a consistently high level of service, underpinned by expert guidance and industry knowledge. Every project is approached with a structured, client-focused process, ensuring clear communication, efficient delivery, and outstanding results. Regardless of the size or complexity of the project, we work in close partnership with our clients to accurately interpret their vision and requirements—translating them into expertly crafted spaces that meet the highest professional standards.
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Latest review:
We initially hired Michael to convert a bathroom into an office. After meeting him and discussing our longer-term plans, we quickly felt confident moving forward with him on much wider renovation works across the property. Michael worked closely with us throughout the entire process—from early ideas and structural planning through to execution. He consistently provided insightful, practical advice that added real value. His ability to anticipate issues early not only prevented problems but also helped us save money by refining the plans to maximise our goals and avoid unnecessary costs. Michael’s broad knowledge and skill set were hugely beneficial on a project of this size and within a tight budget. He made the process far less stressful and, at times, genuinely enjoyable. He kept me informed and involved at every stage, which gave me a great deal of confidence in both the quality of the work and the decisions being made throughout. Michael helped us renovate every corner of our four-bedroom maisonette in West London—from bathrooms and structural opening-up works to a full kitchen renovation, hard landscaping, flooring, and carpentry. The list goes on. His wide skill set and depth of knowledge were truly impressive and exactly what we needed, particularly as we chose to stay closely involved in the renovation rather than hiring a larger construction and project management company. We genuinely don’t feel we could have made a better choice. It’s not always easy to find a builder who is reliable, honest, and trustworthy, so I feel very fortunate to have worked with Michael. I would recommend him without hesitation and will absolutely continue to work with him on future projects, big or small.

4.2

Top rated Extension Builders

Our Extension Builders in St James, are rated 4.2 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.