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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H&M Construction
Rating: 5 out of 5
Extension Builder in St James
We do carpentry and roofing works. We present our work professionally. We strive to please the customer. We have experience over the years. Our prices compete with everyone. Our headquarters is in London
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Latest review:
Carpentry- 27 Mar 2022
We were very happy with Hesham’s work on a tricky job mending our Victorian window shutters.
RBS CONSTRUCTION UNIT
Rating: 5 out of 5
Extension Builder in St James
At RBS we specialise in commercial/domestic building work such as garden rooms, extensions, and renovation work. Whether the job is big or small, we take pride in the work we do and your best interest is always our priority. If you are in London or surrounding areas get in touch for a free quote, it would be our pleasure to help you be a step closer to having your dream home.
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Latest review:
Bricklaying- 6 Jul 2023
Very happy with the job done. Completed to a high standard.
Surwilo Construction ltd
Rating: 5 out of 5
Extension Builder in St James
Surwilo Construction cover all aspects of general building, construction and refurbishment works. Our aim is to exceed our client's expectations, it is around this philosophy that our reputation has been built. We pride ourselves on high attention to detail in the execution of every job undertaken.
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Latest review:
Kitchen Fitting- 2 Jun 2025
Karol was an excellent tradesman and really takes pride in the work he does as if it’s his own place. Highly competent and hard-working and always suggesting the best approach. It’s clear that he wants to ensure his customer is completely satisfied with the work that he completes. He is also very friendly and a great chat. He did a fantastic job in the kitchen and I highly recommend him to anyone looking to do similar work.
AVR Construction
Rating: 5 out of 5
Extension Builder in St James
I have a 10 years in construction industry ( landscaping) dancing paving foundations and many more For a fare quote contact me .
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Latest review:
Garden Maintenance- 21 Jul 2026
Arrived on time. Job completed to a high level. Very satisfied with the work done.
GB Works Ltd
No reviews yet
Extension Builder in St James
GB Works Ltd is a family-run construction company operating across London and the South East. Established in 2008, we deliver reliable, quality-led construction, refurbishment and maintenance services for both residential and commercial clients. We pride ourselves on a professional, hands-on approach, offering tailored solutions to suit each project’s requirements. Our team is committed to delivering high standards of workmanship, clear communication, and safe project delivery from start to finish. A portfolio of completed projects and references can be provided upon request. We welcome enquiries from both new and existing clients and look forward to building long-term working relationships.
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T&S Construction
Rating: 5 out of 5
Extension Builder in St James
Ive been in building work all my life and im very good so people say theres not many builders like me ,try me and i bet you have me back i can show my work .
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Latest review:
Extensions- 2 May 2018
Tom is a very competent builder, who has attention to details. Tom continuously went out of his way to find ways to meet my requirements, Whenever we had atypical challenge during my extension Tom's default position was "let's find a work around." He was creative and efficient in doing so, and most importantly cost effective, as I was running on tight budget. Fantastic experience working with Tom, he estimated the work to complete in 6 weeks, the work was done 5 and a half weeks and handed over. The works speaks of itself, very urban finish with high level of professionalism. I was almost hands off the project due to work travel, and Tom took care of all the aspects without me being involved day to day and micro manage. He is surely being to be big league builder in no time. I would recommend him whole heartedly.
FERARU GROUP BUILDERS LTD
Rating: 4.7 out of 5
Extension Builder in St James
I've worked in the UK for 8years now and I do my job to a high standard.
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Latest review:
Extensions- 15 Jun 2024
My advice is avoid. Poor communication Poor workmanship Poor quality finish Create 'issues' during build to make you pay more than quoted Left project incomplete We pursued through the Court and won the case, but of course he is unable to pay, so we are pursing further through the Court. He will respond to the review with some excuse, but there is absoultley no excuse for poor workmanship and quality. Happy to share pictures and videos on request.
Gluh Inc Ltd
No reviews yet
Extension Builder in St James
GLÜH INC LTD is a specialist facade and cladding contractor based in Essex, operating across the UK. We work with principal contractors, developers, and housing associations to deliver expert facade installation, cladding compliance, fire remediation, and site support services. Our core services include: - Labour-Only Facade Installation (curtain wall, rainscreen, SFS systems) - Labour & Materials Package (supply and fix, single-point delivery) - Cladding Compliance & Fire Remediation (post-Grenfell building safety regulations) - Site Support Services (facade managers, site supervisors, H&S oversight) - Defect & Snag Surveys (snagging, inspections, close-out reports) All operatives are CSCS-certified. We provide full RAMS documentation and work in full compliance with UK building safety regulations. We pride ourselves on quality workmanship, professional site management, and transparent communication from enquiry through to project completion.
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Future Shapes
Rating: 4.9 out of 5
Extension Builder in St James
We are a company who believe in building an outstanding relationship with each and every one of our clients. We pride ourselves on achieving impeccable standards of work, earning trust with our clients through our friendly, reliable, thorough and clean work. We now have an exceptional reputation for delivering fantastic results and over-delivering on expectations with our clients.
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Latest review:
Restoration & Refurbishment- 31 Aug 2020
It was a pleasure dealing with Peter and his team from start to finish and we couldn’t be happier with the work that they did. I was impressed with Peter’s previous work and we developed a good rapport from the first meeting and I felt that I could trust him with the work. He was clear about the detail of the work that needed doing upfront and his quote was itemised to reflect what each element would cost. The work was done on time and of a high quality and Peter was responsive at all times to any questions or concerns we had. He also made great suggestions of how we could do things better and was open to our ideas and realising our dream. His team were punctual, friendly and took care of the house ensuring the work that they did was of a high standard at all times and attention to detail which really has made a difference now that the project is completed. I wouldn’t hesitate to recommend Future shapes to anyone and would certainly use them again.
HNL Construction Limited
Rating: 5 out of 5
Extension Builder in St James
Home improvement company. Experience since 2005.Our job is our passion.Let us make Your dream project.Every job its important to us from small to big. We do: -kitchen -bathroom -loft conversion -extension -refurbischments -electric -plumbing -gardening …and many more
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Latest review:
Conversions - General- 23 Mar 2026
Pawel and his team are great - got them in for a few things now, from damp repair, knocking through an internal brick wall, moving a fuse box, installing a wood floor. Always good workmanship, easy comms and decent value! Have recommended to a few friends who are equally pleased.
Multiservice Solutions LTD
Rating: 4.9 out of 5
Extension Builder in St James
At Multiservice Solutions LTD, we pride ourselves on being a team of multi-skilled, experienced, and reliable handymen and service providers. We are dedicated to delivering top-notch services across London, ensuring your needs are met with efficiency and professionalism. Whether you require sash window installation and refurbishment, end-of-tenancy cleaning, or comprehensive property management, we've got you covered.
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Latest review:
Windows & Doors (Wooden)- 30 Mar 2026
I hired Endri for 1 double glazed unit replacement, repair and repaint my wooden windows. He was professional and well mannered from the start. He did a fantastic job on the windows, now they look as good as new from the inside. I'd be happy to hire him again in the future.
Rose and Stone Limited
Rating: 5 out of 5
Extension Builder in St James
Whether it is an extension or large-scale scheme, we take dignity in taking the client’s vision through to delivering a quality project at the right time and cost. This is made possible by the company being excelled by a Chartered Architect with broad construction experience and a fine eye for detail. A valuable understanding of both traditional and modern techniques along with a firm grasp of materials enables us to provide the client with opportunities to make their concepts a reality.
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Latest review:
New Builds- 7 Jun 2022
Sohail worked closely with me on this project. Providing detailed costings, work schedules and build timelines. Filling my knowledge gaps with his extensive experience he was able to assist over and beyond what I expected from him. Unfortunately due to circumstances out of my control this development project didn’t go ahead. However when the next opportunity for a new build comes up I will definitely be using Rose and Stone. I did have another job going at the time where the other builder badly let me down and left me with a big problem on my hands…. Sohail and his team stepped in and took on the project. The team finished the job exceptionally well, which was a full on top to bottom conversion, some internal reconfigurations and with the addition of a loft and new downstairs WC. The workmanship and overall quality of the job was excellent. My wife is over the moon with the results, taking the house from a three bed one bathroom to a four bed 3 bathroom house. We would definitely recommend Rose and Stone for this type of extensive refurbishment/loft conversion work and look forward to working with them in the future on bigger development projects.
Sukhvir
No reviews yet
Extension Builder in St James
Bathroom,tiles,plaster, extension, new build,
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Restora Developments LTD
Rating: 5 out of 5
Extension Builder in St James
Hi! Here at Restora Developments we pride ourselves in having a diverse range of skills. Our bread and butter is new build homes and large developments, however we have formed a sub division aimed at end clients and home owners for smaller taks. With all in house; - carpenters - roofers - plumbers - electricians - brick layers - landscapers Etc. We take on all work from simple bathroom refurbishments to building your dream property from the ground up!
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Latest review:
Groundwork & Foundations- 18 Feb 2022
they did for me a good job and very high standard and price wise
Oakley Renovations LTD
No reviews yet
Extension Builder in St James
We pride ourselves on being a luxury refurbishment company, with your experience at the heart of everything we do. We started as a property development company now with a GDV of £6million, it was the struggle to find a construction company which matched our expectations of service which led to this arm of the company being formed. Our vision is built around 4 pillars; - Professionalism - Organisation - Communication - Quality Craftsmanship
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Capital Loft Conversions Ltd
No reviews yet
Extension Builder in St James
Our company specializing in high-end residential construction, property refurbishments, designing and installation of high-quality custom loft conversions and house extensions across London and the M25. While offering a personalised service, we bring the skills and experience required to ensure your loft conversion is completed to the highest standard and agreed timeline. Whether you are looking to add value to your property or create more space, our team will handle everything from planning permission to architectural design and construction. Use our experience and free initial consultation to understand the value we can add to your home.
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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.