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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Two Brothers Refurbishment
Rating: 5 out of 5
Extension Builder in St James
At Two Brothers Refurbishment, we don’t just build and renovate — we transform spaces, improve lives, and bring our clients’ visions to life. Built on trust, craftsmanship, and a strong work ethic, our company has quickly earned a reputation for quality and reliability in the UK construction and refurbishment industry. Two Brothers Refurbishment is a family-rooted construction company with a passion for building done right. With years of hands-on experience in a wide range of projects, we have built a team of skilled professionals — carpenters, builders, electricians, plumbers, and decorators — who share one goal: to deliver top-quality work, every time.Our mission is to provide comprehensive construction and renovation services that are tailored to the unique needs of every client. We aim to create functional, beautiful, and lasting spaces while maintaining the highest standards of professionalism, communication, and care. We specialise in a broad spectrum of residential construction services, including: -Home Extensions & Loft Conversions -All aspects of structural work -Full Refurbishments & Renovations -Kitchen&Bathrooms -Renovation&Refurbishment -we can Create/Design/Build -All insurances in place
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Latest review:
Extensions- 30 Jul 2025
We are delighted with the work done by Saby and Mikhail, very easy to work with, high quality finish and they listened to all our requests. 5 stars all the way.
Ben
No reviews yet
Extension Builder in St James
Over 10 years of experience in the building trade, building new and outstanding homes. Specialised in loft conversions, house extension, kitchen refurbishment, bathrooms, full house remodel and refurbishment, garden and pavements, roofing and repairs, certified plumbing, gas and electrician.
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Marble Line Interiors Ltd
Rating: 5 out of 5
Extension Builder in St James
Hi, I’m Ivan from Marble Line Interiors Ltd. We specialise in plumbing, heating, bathrooms, and property refurbishment across London and the surrounding areas. We take pride in delivering high-quality workmanship, clear communication, and reliable service from start to finish. Whether it’s a boiler installation, bathroom renovation, decorating project, or general property improvements, every job is completed with care and attention to detail. We provide free quotations and honest advice, and we’re fully insured for your peace of mind.
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Latest review:
Gas Work- 26 Feb 2024
Ivan and his colleague provided a very good service at a competitive price. They completed the job on time and left the site in a tidy state. Happy to recommend Marble Line Interiors
Urban Construction Management Limited
No reviews yet
Extension Builder in St James
We have been in business since 2015, and working with a number of leading contractors within the construction industry in the country. We have carried out works from new builds to refurbishments, and specialise in loft conversions and extensions, garden rooms, kitchens and bathrooms, and structural alterations. We have all the relevant insurance - employment liability, public liability and professional indemnity cover. We are certified by Construction Line, CHAS, Safe Contractor and BMTrada (Fire Door Installer).
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CSKA 1948 Ltd.
Rating: 5 out of 5
Extension Builder in St James
Using STAR Construction, gives you peace of mind that you are choosing a Contractor who uses properly trained and qualified operatives. All materials used are of the best quality and all work is fully Insured and Guaranteed. We offer a competitive price and our work is of the highest standard. If you have seen the home of your dreams, we at STAR Construction will make sure that this home will become a reality! Here to help, so do not hesitate to contact us.
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Latest review:
Kitchen Fitting- 21 Mar 2016
Vass and his team installed our Magnet Kitchen to perfection he utilised every space with great ideas I could not give enough praise for his craftsmanship and he takes great pride in his work, I would definitely recommend him. Thanks to Vass & Anthony
Inspired Creations London Ltd
Rating: 5 out of 5
Extension Builder in St James
We undertake residential and general construction projects including extensions, loft conversions and renovations. We also manufacture and install bespoke kitchens, bedroom and all kinds of fitted furniture.
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Latest review:
Extensions- 8 Dec 2021
Sukh and his team are tidy, experienced and skilled. The standard of work throughout the house is excellent. Will be keeping their contact details for any future projects. Would definitely recommend.
Peterbuild
No reviews yet
Extension Builder in St James
I currently work for my self as a solo trader all my work are by recommendation but i will like to try something new. work i undertake are general building work for example, bathrooms refurbishment , kitchens ,plastering etc.
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Home & Office Improvements Ltd
Rating: 5 out of 5
Extension Builder in St James
We are a long established family business based in Greenford, Ealing. We cover all aspects of Plumbing & Heating, we also install all types of boilers, boiler repairs, boiler breakdown, boiler service, central heating systems, AGA-Rayburn cookers repair & Service, quality kitchens and bathrooms.
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Latest review:
Arrived on time. Very professional. Gave consultation and did the job in good time.
worksite solutions ltd
Rating: 3.5 out of 5
Extension Builder in St James
HELLO MY NAME IS IULIAN NICULCEA AND I HAVE BEEN WORKING SINCE 2013 IN THE UK AS A CARPENTER / SITE MANAGER ...I HAVE THIS SMALL COMPANY AND I WOULD LIKE TO BE ABLE TO HELP YOU WITH DIFFERENT SERVICES....
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Latest review:
Groundwork & Foundations- 26 Jun 2026
Good
Danny construction
Rating: 5 out of 5
Extension Builder in St James
I have over 20years of experience in window fitting , during which I've gained experience and always worked on mastering my skills in installation, repair and customer satisfaction. I enjoy doing this job both independently and as part of a team( have worked for different companies before). I'm committed to meeting deadlines and delivering quality workmanship on every project and exceeding customer expectations.
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Latest review:
Windows & Doors (uPVC & Metal)- 9 Feb 2025
Excellent work, very professional, good price. I would use him again. Great communication and I was very pleased he was available the next day.
Muneeb Qamar
Rating: 5 out of 5
Extension Builder in St James
As a bathroom specialist, I have the skills to handle plumbing and electrical work. From fixing leaks to installing fixtures, I've got you covered. Let's work together to create a beautiful bathroom that meets your needs and exceeds your expectations!
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Latest review:
Bathroom Fitting- 6 Mar 2026
What a great team! Muneeb and his team finished the job in time, turned my tired old bathroom into a wonderful new space. Price quoted was half what we were being quoted by others. Muneeb just focused on this job rather than many others who leave the customer waiting whist doing multiple jobs. All materials used are top quality and nothing was too much for him. Muneeb kept variation minimum and agreed details in advance. Thank you Muneeb and team
Rc builders
Rating: 5 out of 5
Extension Builder in St James
Family run company with 20+ years experience using time served and fully qualified tradesmen Finishing to a high standard regardless of your budget. All work fully guaranteed
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Latest review:
Restoration & Refurbishment- 30 Apr 2026
Job was completed quickly and to a great standard. Reasonably priced and we would definatley use them ahain
Propertyxhub Limited
Rating: 5 out of 5
Extension Builder in St James
An experienced building trade specialist team with all qualified professionals. From new build to small work, we are happy to help you honestly.
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Latest review:
Plumbing- 2 Jun 2026
Thank you for doing that for me just give me a shout. I will do thank you very much. Thank you very much. I had in my car. Thank you for fixing my shower now I can have a shower without giving the whole bathroom a shower when I want a shower and for showing me that you have fixed my shower I very much appreciate you taking the time to come and fix my shower I am eternally grateful
Coulsdonbuilders Ltd
Rating: 5 out of 5
Extension Builder in St James
Coulsdon Builders has been successfully making home improvements for over 15 years. We are ready to fulfill your needs as a builder. Whether you desire a full renovation to create your new dream home or home improvements or general enhancements to add value and space to your property, we are here to assist as a contractor. Coulsdon Builders can propose and carry out the best building solutions for you to achieve your building goals, within your budget and in a short time-frame.
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Latest review:
I wanted a side infill extension, converting a one bed into a 2 bed. The works was undertaken by Coulsdon Builders which took around 8 months. I made several changes throughout the project hence the delay. They were so accommodating and never had an issue and was always happy to cooperate. The cost of build was £120k and we stuck to the budget. I am delighted with the works and am grateful they made my house a home. They were clean and tidy on a building site and always kept me updated on progress. This is one builder that I highly recommend and trust. Great work guys and thank you again!
Build tech
Rating: 5 out of 5
Extension Builder in St James
Welcome to our add. Professional Building Company Professional experts in all types of construction have worked on Victorian and Georgian properties, giving them a slick new light and converting them into modern and contemporary living spaces. Expect transparent open-book pricing, quality workmanship, and 24/7 communication.
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Latest review:
Extensions- 28 May 2019
Ayaz is a professional and a really nice man.
Griffithstown Group
No reviews yet
Extension Builder in St James
Time served builder who takes on general building works
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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.

Quality screening

Easily find verified local tradespeople. Just post your job to get quotes from tradespeople near you across the UK.

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.