Extension builders in St James

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.6 (22 reviews)

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Some of our top rated extension builders in St James

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96 Degrees Carpentry Ltd
Rating: 5 out of 5
Extension Builder in St James
We undertake all aspects of Carpentry and General building works. Specialising in refurbishments and loft conversions we have a team of qualified and experienced carpenters, plumbers and electricians available for both residential and commercial works.
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Latest review:
Decking- 23 May 2021
Excellent and professional job completed as quoted. Would highly recommend to future Clients.
Jeffery and Wilkes Ltd
No reviews yet
Extension Builder in St James
Jeffery and Wilkes are an award-winning, leading construction company in London.Jeffery and Wilkes have numerous positive reviews & testimonials from their previous clients. As a family run, boutique business working on London's finest properties & based in Kensington, we know how important quality is and creating beautiful, elegant spaces in our clients home.
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Bardy construction ltd
No reviews yet
Extension Builder in St James
IBardy Construction Ltd, a skilled team of building and home improvement specialists with over 10 years of experience in the trade. We handle all types of home renovations, including loft and basement conversions, room extensions and kitchen and bathroom remodelling. Our goal is to provide a high-quality, affordable service that exceeds our clients’ expectations every time.
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Reva Projects Ltd
No reviews yet
Extension Builder in St James
We take pride in offering outstanding quality services in an array of sectors in which we operate. With over 25 years of experience in the building industry, our highly experienced team ensure a comprehensive and uniquely personal service, embracing both public and private work in the residential and commercial sectors.These include design, planning and construction of residential and commercial projects. We provide an unmatched level of service from the first enquiry until final handover.
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Eliana Solution Ltd
New on MyBuilder
Extension Builder in St James
13+ years of loft conversion experience. Quality workmanship,honest service and attention to detail.From start to finish,I deliver loft conversion built to last.
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ABS 23 Ltd
No reviews yet
Extension Builder in St James
we are working in the industry for the last 15 years we provide every type of building works
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Morris Carpentry & Construction ltd
Rating: 5 out of 5
Extension Builder in St James
Morris Carpentry & Construction are a family run business with over 40 years experience within the building industry. All our team are fully qualified in their own individual trades, which covers all aspects of building projects. We take the upmost pride and satisfaction in all of our work and treat your home like our own. We are more than happy to provide free estimates for any work you may require.
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Latest review:
From start to finish perfect, very good communicator, no hidden extras, very clean, can't knock him or the lads at all Many thanks Jack for a job egoless done Highly recommend
Bulbuilder
Rating: 4 out of 5
Extension Builder in St James
I am from Bulgaria.
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Latest review:
Lovely father son business, professional, friendly guys. I asked them to build a plasterboard wall in order to create an extra bedroom in my house, the wall was finished well, within two days and they charged me a very reasonable rate, as a young women in business I find that tradesmen often try to overcharge me but these gentleman did not. They also took a look at leak that had occured which another professional plumber failed to solve and tried to charge me over £200 just to take a look! I have and will book them on a number of other jobs.
SRK Constructions London Ltd
Rating: 5 out of 5
Extension Builder in St James
We offer a plethora of construction services and are known for excellent k-rendering, electrical fitting, plumbing, and carpet service. We have been in the industry for more than 14 years and our work varying from small to large projects speaks about our experience in the field. We believe in creating with heart and building with the mind. We are trustworthy contractors and always strive to meet the quoted budget. Clients’ satisfaction is the topmost priority of the SRK constructions.
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Latest review:
Bathroom Fitting- 12 Apr 2022
Sandeep was the first builder who I ever met who finished job before time . His team has worked very hard and did job as per our expectations . Before this I used 3 different builders and no one finished job on time . I will recommend him for any building related job .
A&z
Rating: 4.7 out of 5
Extension Builder in St James
Hi I’m Zan, I have 12 years of experience working as a groundwork engineer. I am offering good discounted prices whilst I establish my business! I offer the following services: -Digging foundations and all general groundwork -Gutter cleaning -Roof damage repair -Demolition -Pipework
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Latest review:
Groundwork & Foundations- 25 Oct 2026
Good work and communication, came back and finished the job
Jim building services ltd
Rating: 5 out of 5
Extension Builder in St James
Great Team over 20years experience, we specialise in Lofts, Extension, Bathrooms, Kitchen & Full Refurb, We pride ourselves in what we do, we are dedicated team consentrating a project at the time making sure always deliver Quality & ontime. Clean,tidy & attention to detail panctual, always friendly & great costumer care Thank you
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Latest review:
Extensions- 30 Dec 2024
I am extremely happy with Jim and team's work. Their work is of high quality and they give attention to details too. I received a lot of positive feedback from friends/family on the extension work they have done. I can confidently say that he's delivered a quality work for a very reasonable price. Jim consulted us throughout the building process making sure we're happy with the decisions. If he found out anything outside the project work, he'd inform and fix it. I agreed to carry out some additional work including front side rendering, bathroom refurbishment and changing some internal doors. He completed all additional work timely and for a reasonable price. I highly recommend Jim for any building work. I'll be going with Jim for any building project in the future.
Emerald london building solutions fixed
Rating: 4 out of 5
Extension Builder in St James
Refurbishment and building contractors/carpentry Contractors we are master builders and a reputation of being excellent at a reasonable Price all work is backed by guarantee on all works
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Latest review:
Restoration & Refurbishment- 15 Jun 2020
Left the job unfinished after many days of chasing to complete. Quality dependent on individual tradesman. Initially good quality but other workmen poor. In the end I had to throw them offsite.
Builders World Supplies Ltd
No reviews yet
Extension Builder in St James
The company specializes in total home or flat renovations and house extensions. The team has actively participated in both large and small scale construction projects in London over the last 15 years. The quality of the work is outstanding and we can fit any budget. Our experience and our extensive contacts in the industry enable us to offer solutions suitable for the customer's needs. The founder and Director of the company is a qualified Civil Engineer.
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Area Property Care LTD
No reviews yet
Extension Builder in St James
If you are looking for a company providing comprehensive construction and renovation services we have the skilled team. Area Property Care provides refurbishments in general and construction of extensions and loft conversions. Engineers on the road help clients for small repairs / maintenances. We cover London area. Please contact us and get a quote for free.
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Spekbilt Limited
New on MyBuilder
Extension Builder in St James
Spekbilt Limited, alongside its partners, is a building contractor specialising in high-quality residential conversions, home extensions, structural alterations, and full internal refurbishments. We bring commercial-grade precision, safety, and project management to private domestic projects. Whether you are looking to execute a loft conversion, garage conversion, open-plan structural knockout, or complete luxury home renovation, our experienced site teams deliver exceptional craftsmanship from start to finish. Why choose Spekbilt? • Total Structural Expertise: Specialists in RSJ steel installation, load-bearing removals, wall reconfigurations, and space optimization. • Full Building Regulations Compliance: Fully versed in UK Building Control requirements, thermal efficiency standards, acoustic insulation, and fire safety. • Turnkey Project Management: Complete care from initial site setup to first/second-fix carpentry, plastering, electrical systems, kitchens, and bathrooms. • Clear Communication & Reliability: We work transparently alongside homeowners to ensure projects stay on schedule, within budget, and built to exact specifications.
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Building life uk limited
Rating: 4.8 out of 5
Extension Builder in St James
My skills are :Tiling :brickwork :extensions :loft conversions :partition : painting :carpentry E.t.c :you name it we do it I've got a team together who are hard working men who are very motivated on working together with our clients we always keep everyone who we do work for happy and still get recommended I work references that I can provide (We haven’t been online at my builder over a year now but we have been working out from my builder we got lots of work to prove)
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Latest review:
Bathroom Fitting- 9 Oct 2018
Ozay arrived on time and finish the job to a high standard I've used the shower for over a month now and no leaks! Would use again!

4.6

Top rated Extension Builders

Our Extension Builders in St James, are rated 4.6 out of 5 based on 22 reviews from customers like you.

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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.