Extension builders in St James

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.6 (20 reviews)

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Some of our top rated extension builders in St James

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Renovations.Tm
Rating: 5 out of 5
Extension Builder in St James
We are an experienced and reliable company specializing mainly in extensions, basements, conversions, skylights. We can carry out renovations or building works to your dream home. As we say, Well Done Is Better Than Well Said, come and check us out now !!!
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Latest review:
Tomasz and team did various jobs for me (wooden floor, skirting boards, acoustic wall and floor insulation, plastering, painting, electric work etc). Top finish and workmanship, extremely professional and reliable, friendly, helpful, considerate, punctual, honest, tidy worker.
Rcm Buildrs
Rating: 5 out of 5
Extension Builder in St James
RCM Builders is an insured construction company which offers a multitude of services. Loft conversions, extensions, painting, plastering, fencing, building renovations, and bricklaying are a few specialities we covers. We have over 28 years worth of experience and are well versed in providing high quality work, great customer service, great costumer satisfaction and great communication.
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Latest review:
Conversions - General- 7 Mar 2023
Have completed the job extremely well. Did a new door opening. Door fittings and plaster work . Very good finish. On time. Polite. Very pleased. Would hire again.
365 BUILDING LTD
Rating: 5 out of 5
Extension Builder in St James
At 365 Building, we focus on quality over quantity. With many years of experience across a wide range of construction and carpentry projects, we take pride in delivering work that is done to a high standard, completed on time, and kept clean and tidy throughout. What We Do We offer a full range of building services, including: • Carpentry & woodwork • Kitchens & renovations • Flooring & doors • Roofing • Extensions • General building and property improvements We approach every project with care, precision, and professionalism—whether it’s a small repair or a full home improvement. Why Customers Trust Us Our customers appreciate our attention to detail, respectful working style, and strong workmanship. We aim to make every client happy, and many of our projects come through recommendations from homeowners who value the quality of our work.
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Latest review:
Hard Flooring- 23 Jan 2026
Great and honest work, very quick and flexible. Would 100% recomend
Cole and Son decor ltd
Rating: 5 out of 5
Extension Builder in St James
I'm a very honest, reliable and hard working person. I always leave the job I started in very good condition and completed in the allocated time. I always provide the client with the best solutions for the job and keep my costs clear and fair.
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Latest review:
Victor (Vica) laid some engineered oak wood flooring for us in a house that we bought at the end of 2013. The house needed lots of work doing and the new flooring was just one of the many jobs undertaken by Victor and carried out to a very high standard for us. He always paid attention to detail, ensured that the flooring was level and that the new skirting board fitted flush to the floorboards. He was also always able to provide a solution to any problems encountered during the renovation works. I would have no hesitation in recommending Victor as he takes the same pride in his work for others as if he was carrying out work in his own home.
Patrick JR
Rating: 5 out of 5
Extension Builder in St James
Experienced Tradesman who enjoys providing a friendly and reliable service to customers. No job too small from Demolition and groundwork’s to first fix of structures to second fix finishing jobs such as hanging TVs and mirrors. Please get in touch for a no obligation quote and estimated timescale.
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Latest review:
Handyman- 4 Aug 2021
Great during the pandemic, able to change appointment due to isolation. Job completed in a timely manner and work space left clean. Job completed a month ago and still perfect. Thanks
Jozeph
Rating: 5 out of 5
Extension Builder in St James
I am a professional and reliable tradesman who works to very high standards, these standards have helped me to build up an excellent reputation with regards to all work that I have carried out. Please request a quote through mybuilder.com for a free and honest estimate ,painting decorating ,loft ,extension ,kitchen ,bathroom ,carpenter etc.
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Latest review:
Handyman- 3 Oct 2015
Fast, efficient, friendly builder. Very skilful, quality work at a reasonable price. Couldn't be happier. Fully recommend Jozeph. Emma & Emanuel
Bass Construction Ltd
Rating: 5 out of 5
Extension Builder in St James
A multidisciplinary construction firm with a focus on custom construction, Bass Construction/Design was established in 2013. Our team provides services for residential and commercial properties from the planning to construction stages with the goal of creating spaces where functionality and aesthetics coexist.
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Latest review:
Extensive work including a double height extension, reconfigured layout on two floors, large area of glazing, roof lights, kitchen and bathroom fitting, laying of a patio and other ancillary work. The work was carried out by Bruno, Roberto and the team to the highest standards with great attention to detail and with care. The completed project was beyond our expectations.
Mario Services
Rating: 5 out of 5
Extension Builder in St James
Mario & Alex Construction LTD specialise in construction and building services, complete property refurbishment, house extensions and loft conversions. Provides unmatched customer service. Our commitment to small,hudge integrity, providing the highest value and satisfied customers, has been the ingredient that has fueled our growth from the beginning. We ensure that all our work is professionally managed so that the result is of outstanding quality, cost-effective.
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Latest review:
Bathroom Fitting- 20 Jan 2023
We highly recommend Mario & his team. They fitted a new kitchen & bathroom to a really high standard within a short, timeframe. They work hard, are friendly, professional & honest, my neighbour even commented on how considerate they were! Upon first meeting Mario we were impressed by how organised he was. He arrived on time with the description we’d posted on my builder & went through it methodically. We had A LOT of questions! He answered all of them & didn’t rush us. We received a competitive quote within a day as promised. It included everything we discussed & he quickly answered our follow up questions. We wanted an accurate idea of the cost of electrical work & Mario arranged for his electrician to come & inspect/quote before we’d appointed Mario the job. Our kitchen & bathroom is complicated, with lots of difficult angles. Damp, unlevel floor, unlevel windows, a low ceiling were uncovered in the bathroom. Mario did well to identify solutions, giving us expert advice. Pipes were neatly chased into the wall. Underfloor heating & LVT, tiling, grouting & painting all done to a very professional finish. He kept us informed of progress, checked our preferences & was patient when we had supply delays, finding ways to ensure the job finished on time enabling us to move from our temporary accommodation back home in time for Christmas. He promptly fixed some minor issues after the job finished. We highly recommend Mario & would use him again.
James Murdoch
Rating: 5 out of 5
Extension Builder in St James
Construction company with 27 years experience in the industry between us and a team of other qualified tradespeople necessary to undertake projects.We are new to this site so please ask us to provide you with reference from previous clients. We have experience in timber frame homes, apartment blocks, extensions, renovations and commercial works.We take great pride in our work and make sure every job is completed to the highest of standards on time and on budget. Our aim is your satisfaction.
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Latest review:
Carpentry- 31 May 2017
Was really impressed with these guys. Helped me order the correct garden door and then went to pick up extra bits when the order didn't turn up correctly, for no extra cost and couldn't have been nicer about it, even though it was a pain for them. Really cheerful and helpful - nothing was too much trouble. Would use them again, for sure.
Lux Development LTD
Rating: 5 out of 5
Extension Builder in St James
With a BSC Hons Degree in Construction management and having worked for larger reputable building contractors in the UK. We will Ensure you get the highest Quality of Work at reasonable Prices. Customer Satisfaction is our First Goal of any Project we Undertake. We undertake all types of construction and building projects from Painting and Decorating, Flooring, Roofing, Plastering to More Complex Projects such as extensions.
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Latest review:
Painting & Decorating- 12 Feb 2019
He truly showed professionalism that I had struggled as a guest house operator to get from handy people. He would go out of his way to satisfy. The finished redecorated room project was a masterpiece and took a little longer than planned because of the weather but he gave it his all! I am pleased I took a chance on him as there was no review on his profile when I hired him. I would however, pay attention to work and point out issues as they come up otherwise, you will have dirt and rubbish to content with as the workers leave all the mess after work.
Inspire Construction Solution LTD
Rating: 5 out of 5
Extension Builder in St James
We specialise in Loft conversion, House extension and all kinds of buildings works
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Latest review:
We did a lot of research ahead of our loft build, and spoke to customers of the companies we looked at. We were impressed with Toma and her team from the outset, especially in terms of clarity and communication. We sat down with the project team at the start and walked through the week-by-week plan for our build, then a whatsapp group and weekly meets meant we knew exactly what was happening throughout. Our endless questions were responded to swiftly. Additional optional trade-ups (eg top-hung windows, larger bathroom window etc) were discussed and explained with context, sound advice (and clear pricing where nec) but always still optional. Toma's communication with the teams also seemed strong and continuous, with materials always arriving in time and ahead of when needed, no down-days etc - and importantly, the teams all seemed happy and were just lovely people to have around. I realise with hindsight too that the team's care and workmanship really put them a cut above many others in my area and the project remained on schedule. I wouldn't hesitate to recommend ICS for the whole package and in fact we've also chosen to use them again for a kitchen extension.
Chris Building Services
Rating: 4.8 out of 5
Extension Builder in St James
Hello! We are a small family business of builders. Friendly & reliable, time-served tradesmen. We are always clean, tidy, respectful and considerate in your property. Qualified Tradesmen and sensible prices, we always aim for 100% satisfaction first time - every time. No job is ever too small, [or even too large!] We are a one-stop shop for anything building related. Take a look at our profile to see what we do..
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Latest review:
Restoration & Refurbishment- 2 Apr 2025
Chris did a wonderful job in the time given, super professional finish and quickly completed! Thanks Chris!
AP General Builders
Rating: 5 out of 5
Extension Builder in St James
Our company is based on the belief that our customers' needs are of the utmost importance. Our team is committed to meeting those needs. As a result, a high percentage of our business is from repeat customers and referrals. I would be more than happy to showcase the high quality of work I/we pride our self in and would welcome the opportunity to earn your trust and deliver you the best service in the industry.
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Latest review:
Extensions- 5 Sep 2019
The builders did an incredible job refurbishing my house. For my house I wanted to break the internal wall to create a bigger living room and also for them to refurbish the toilet. In the beginning they’ve set a period when everything will be done and they’ve stuck to it so they are trustworthy. Seeing the progress, I could definitely tell that they were working incredibly hard and I know that they have been working long hours to ensure that they manage to finish it within the timeframe that they’ve set. I would definitely recommend them.
Jx refurbishment
Rating: 5 out of 5
Extension Builder in St James
My name is James Jiang,I got more than 15 years experiences in the trade and my team has built good reputation in London area. Our aim is to deliver complete customer satisfaction with every project we undertake and ensuring our customer’s visions are met.
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Latest review:
Conversions - General- 22 Oct 2026
James and team were absolutely brilliant. Great price, turned up on time, worked nonstop, great attention to detail, and very tidy. Can’t recommend enough.
Robert Kastrati
Rating: 5 out of 5
Extension Builder in St James
Brick work
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Latest review:
Bricklaying- 18 Jul 2024
Robert is highly professional brick layer, He is polite and communicative. He did excellent job for me. Looking forward to work with his again
Axe Construction Ltd
Rating: 5 out of 5
Extension Builder in St James
Hello and welcome to Axe Construction Ltd. If you are thinking of renovating your home, building an extention or arranging general maintenance in your property, we are here to help. Our priority in job is to deliver high standard service to customer’s satisfaction.We offer a professional and friendly service to all private and commercial clients in and around London We are always go above and beyond to satisfy our clients.We are happy to provide references from our clients and arrange site visit
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Latest review:
Conversions - General- 7 Feb 2019
Paul and his team completed our project timely and at a competitive quote. The team was friendly and easy to communicate with. We had some specific requirement and they were able to find solutions for us quickly. Overall we are happy with their work.

4.6

Top rated Extension Builders

Our Extension Builders in St James, are rated 4.6 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.