Extension Builders in St James

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.1 (17 reviews)

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Some of our top rated extension builders in St James

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Montrose builders limited
Rating: 5 out of 5
Extension Builder in St James
Montrose builders is family run having been established by 2 brothers Neil & Nick. Are expertise and knowledge makes us the first choice in providing building services for both homeowners and commercial enterprises. most of our work comes through recommendations providing an honest testament of the service we provide. our company is run on the cornerstones of being family run, providing quality work for the fairest price, with a company ethos of being approachable, friendly and honest.
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Latest review:
Waste Clearance- 17 Jun 2024
Excellent service, quick responses to messages and queries. Work carried out to a high standard, I wouldn’t hesitate to recommend or use them again.
The Gate Property Management
No reviews yet
Extension Builder in St James
Welcome to The Gate PM – Your Trusted Partner for Complete Home Transformations 📍 Where we work: We cover the wider London metropolitan area, bringing our reliable service to homeowners across London and the surrounding regions. 👷‍♂️ Our experience: With years of hands-on experience in the construction industry, we have successfully completed countless projects ranging from small refurbishments to full-scale extensions. Our portfolio includes everything from listed building renovations to modern loft conversions and new-build extensions. 🛠️ Our special skills: We offer a true one-stop shop for all your building needs. Our in-house team covers: · Full renovations and refurbishments · Extensions, loft conversions, and conservatories · Kitchens, bathrooms, and plumbing · Roofing, flooring, plastering, and tiling · Porch, driveways, and external landscaping · Electrical installations and rewiring · Painting and decorating ✅ Why hire us: We believe in honest communication, transparent pricing, and exceptional craftsmanship. Every project is managed personally from start to finish, ensuring quality control and peace of mind. We're fully insured, pride ourselves on cleanliness and reliability, and won't leave.
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MS builder
Rating: 5 out of 5
Extension Builder in St James
My company working in construction field from last 6 years. With the help of many years experience we finish our work with good quality on time and provide customer satisfaction.
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Latest review:
MS builder done our house refurbished and renovated, they provide very qualitative work. Their team members are very helpful.
Top Finish Ltd
Rating: 4.6 out of 5
Extension Builder in St James
We are a property refurbishment specialists with a wealth of experience in house extensions,basements,loft conversions,bathrooms kitchens and much more. We have built a reputation on the basis of providing clients with a quality service that is combined with excellent value for money. .
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Latest review:
Extensions- 16 Dec 2014
These guys were amazing!!! They have done a fanstasic job. There standard of work was extremley high. They turn up on time every day monday to friday and they also offered to work the weekends to speed up the project if needed...... which i did. The price was very competitive and i would definitely use them again always! Get them while you can!
RD PAINTING & RENOVATIONS LTD
No reviews yet
Extension Builder in St James
RD Painting & Renovation provides professional painting and renovation services for homes and businesses. We handle everything from interior and exterior painting to repairs and remodels, always focusing on quality, reliability, and customer satisfaction. Our goal is to make every space look its best and meet the unique needs of each client.
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AP Holloways
Rating: 5 out of 5
Extension Builder in St James
A P Holloway’s Construction Ltd is a leading and reputable Construction Company serving central London, Kent and Surrey. We take on all types and sizes of projects, and cover all aspects of residential and commercial construction.
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Latest review:
Plastering- 5 Sep 2023
Alfie & Paul were very friendly and gave good advice. They were efficient and on time. Did the job on time and within the specified time. I have no problems with their work and would recommend them to others.
A claire
Rating: 5 out of 5
Extension Builder in St James
Hi there I can do anything from A-Z with the best prices and to top quality finish, free estimations is available Best prices you’ll find from me 😜
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Latest review:
Tiling- 30 Apr 2026
Job was done to a professional standard. Very satisfied.
Darko
No reviews yet
Extension Builder in St James
I’m a skilled handyman, carpenter, and joiner with extensive experience in flooring and tiling. Known for building strong rapport with clients, I bring meticulous attention to detail and a deep respect for others’ time. I take pride in every project I undertake, consistently applying my knowledge and refining my craft throughout the week. Reliable, precise, and passionate about quality workmanship.
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Ava Constructions & Decors
Rating: 4.9 out of 5
Extension Builder in St James
Ava Constructions & Decors Ltd is a UK-based construction and renovation company committed to delivering top-quality craftsmanship and reliable project management. We specialise in full refurbishments, extensions, bathroom and kitchen installations, and commercial fit-outs — always tailored to the client’s vision and delivered to the highest UK building standards. With a keen focus on transparency, timelines, and customer satisfaction, Ava Constructions has earned the trust of homeowners, investors, and developers alike. Punctuality and completion of work on time are a priority .Our team always respect the client wishes and work with them to achieve the best possible results to their satisfaction. Thank you in advance
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Latest review:
Extensions- 16 Apr 2026
I would not recommend this builder based on my experience. Instead of using crushed concrete they used soil to fill the house flooring for underfloor heating. 1 The project suffered from poor communication, repeated delays, and a lack of clarity around responsibilities. There were serious issues with the foundation works, which failed Building Control inspection and now require remedial engineering input before works can proceed. The site was also left incomplete and not in an acceptable condition. Despite substantial payments being made, key documentation, technical responses, and follow-through were lacking, leaving me to resolve major compliance and structural issues independently. My experience has resulted in delay, additional cost, and considerable stress. I would strongly advise others to ensure there is a detailed written contract, clear scope of works, and defined accountability
STM Contractors
No reviews yet
Extension Builder in St James
STM Contractors is a leading construction and project management firm dedicated to delivering high-quality services to clients across various industries. With a team of skilled professionals and a proven track record, we specialize in providing comprehensive solutions for residential, commercial, and industrial projects.
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JIMGOS Maintenance LTD
Rating: 4.4 out of 5
Extension Builder in St James
Jimgos Maintenance Ltd is a London-based property maintenance company delivering reliable, high-quality services across a wide range of trades. We specialise in residential and rental property works, supporting homeowners, landlords, and managing agents with both reactive and planned maintenance. * Gas & heating – boiler installations, servicing, gas safety certificates (CP12), heating system repairs * Plumbing – leak detection, pipework repairs, bathroom installations, drainage solutions * General building & refurbishment – tiling, plastering, painting & decorating, kitchen and bathroom upgrades We understand the importance of compliance, safety, and clear communication, especially when working within tenanted properties. Our team ensures all work is carried out in line with current UK regulations and industry standards.
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Latest review:
Central Heating- 16 Jun 2026
The job was carried out efficiently by Kwizie who was also polite, kind and honest, he spotted the issue straight away as my electric boiler stopped heating up the water. Thank you again kwizie! PS: However, The company is not one of the best, a bit pricey as he did the job only for 1 hr changing only the fuse and checked if was working properly.
Row London Construction LTD
No reviews yet
Extension Builder in St James
We offer quality services at an advanced standard , We have a team trained to paint and decorate your home , For any details do not hesitate to contact us, and visit our website. Best team : Row London Construction
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builder
No reviews yet
Extension Builder in St James
14 years of experience in plastering, tiling, bathroom and kitchen fitting. I have my own team of skilled builders
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Simply Extensions and Lofts Ltd
No reviews yet
Extension Builder in St James
We're specialist’s in house extensions, refurbishments and Loft conversions in South London and all surrounding suburbs, with the aim to deliver. Everyone that we use for finishing, is a trade. This gives you a very high quality finish that is seldom achieved by a 'General-trade'. We are fast, clean and produce showroom quality. Our individual professionals are more than just people we work with, they are people we know. We make or exceed our deadlines to ensure client satisfaction!
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Blueprint Developments Limited
Rating: 5 out of 5
Extension Builder in St James
Welcome to Blueprint Builders, where your dream space becomes a reality. Nestled in the heart of London, our team is at the forefront of design and construction innovation. We specialize in transforming spaces into luxurious living experiences, with services that include: - Elegant House Extensions - Meticulous Loft Conversions - Comprehensive Renovations - Bespoke New Builds And a wide spectrum of commercial and domestic building projects designed with your luxury and comfort in mind. At Blueprint Builders, your satisfaction is not just a goal—it's our promise. We're dedicated to bringing smiles to our clients faces through meticulous attention to detail, unparalleled craftsmanship, and a seamless client experience from start to finish. Stay connected with our journey of transformation on Instagram @blueprintbuilder. Follow us for a regular dose of inspiration through updated photos of our latest projects. Dreaming of a space makeover? Don't wait any longer. Contact us today for a complimentary site visit and a personalized quote. Let's make your vision a living, breathing reality.
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Latest review:
We recently had our 3-bedroom house renovated, along with a new rear extension build and a garage conversion, and I couldn't be happier with the results. The team demonstrated exceptional craftsmanship and attention to detail throughout the project. From the initial consultation to the final handover, they were professional, reliable, and transparent about costs and timelines. The renovation completely transformed our home, enhancing both its functionality and aesthetics. The rear extension seamlessly integrates with the existing structure, creating a spacious and light-filled living area, while the garage conversion provides a versatile space we can now use as an office. The team was approachable, accommodating any changes we requested during the build, and always left the site clean and organized at the end of each day. I was particularly impressed with their ability to stay on schedule despite some challenging weather conditions. If you're looking for a dependable team that delivers quality work, I highly recommend Blueprint.
BATKHUYAG BALJINNYAM
No reviews yet
Extension Builder in St James
I working 20 years in the building. Started working labour and now can do plastering, kitchen and bathroom installing , carpentry and decorating jobs
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4.1

Top rated Extension Builders

Our Extension Builders in St James, are rated 4.1 out of 5 based on 17 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.