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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GH Build Specialists
No reviews yet
Extension Builder in St James
NvQ level 6 construction manager with 20 years construction experience.
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Kingston Surrey Construction Ltd
Rating: 5 out of 5
Extension Builder in St James
We are a construction company with over 25 years experience. We Have worked on major projects including extensions, loft conversion and refurbishments. Including smaller projects, new bathroom and kitchens.
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Latest review:
Restoration & Refurbishment- 21 Apr 2024
Got my cloakroom re-done. They r friendly, professional, attention to detail, with clearly tens of years’ experiences. Reasonable rate as well.
Adrian
Rating: 5 out of 5
Extension Builder in St James
Ady Construction Services LTD is a full-service building company providing high-quality construction, renovation, and property maintenance solutions across residential and commercial sectors. From groundwork, brickwork, roofing, and extensions to full refurbishments, kitchen and bathroom installations, landscaping, and decorating, we cover every aspect of building work. With a skilled team, attention to detail, and a commitment to excellence, we deliver reliable and cost-effective services tailored to each client’s needs — from start to finish.
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Latest review:
Landscaping- 23 Mar 2025
Great job - promptly done and good quality!
d&n building construction ltd
No reviews yet
Extension Builder in St James
D&N Building Construction Ltd** Founded in September 2015, D&N Building Construction Ltd leverages over 30 years of industry experience. Our skilled team specializes in a variety of projects, including HMO conversions, loft conversions, home extensions, and kitchen fittings. Last year, we successfully completed a major HMO project in Norwich, overcoming challenges in collaboration with local council and building control. The project received full sign-off, and the landlord was highly satisfied with the results. The building is now nearly fully occupied, reflecting our commitment to quality and client satisfaction.
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Douglas carpentry and building
Rating: 4.9 out of 5
Extension Builder in St James
Douglas carpentry and building has over 10 years experience in all aspects of building work. We as a company have very high standards to accommodate all your building work needs from internal doors, skirting, architraves, built in wardrobes to all general building work. Hard working, dedicated, reliable, clean and tidy and here to give you a fair and honest quote. Please look at previous work on my Instagram page @douglascarpentry23
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Latest review:
Carpentry- 14 May 2026
Replaced a rotten external single door. The existing door frame was reused, as per request. This frame wasn't perfectly square which Alex had to compensate for. Alex arrived on time and completed the work without any unresolved issues, taking all offcuts and old door away for disposal.
Efficient construct ltd
No reviews yet
Extension Builder in St James
Efficient Construct prides itself on their extensive experience in construction management, with over 15 years of successfully completing various projects. Our team of professionals are dedicated to delivering high-quality results, ensuring that every project is completed with precision and attention to detail. We specialize in managing all aspects of the construction process, from design and planning to project completion.
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TNK CONSTRUCTION LTD
Rating: 5 out of 5
Extension Builder in St James
Experienced quality builders. You can rely on us to complete your project weather it’s a straight forward small job or a complicated bigger project with attention to detail.
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Latest review:
Conversions - General- 6 Dec 2024
Amazing builders. Very knowledgeable of building methods and solutions. Very strong and tough guys. Work really hard. Very courteous and patient. Very good results. They replaced a ceiling; built an extension; laid paving stones. All done to complete satisfaction.
Luminous builders ltd
Rating: 3 out of 5
Extension Builder in St James
At Luminous Builders we bring design, build, and refurbishment together under one roof. We treat every property as a living structure — crafted with care, precision, and integrity. Whether you need a bespoke renovation, detailed interior finish, or full property transformation, our mission is simple: to deliver spaces that inspire, endure, and shine.
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Latest review:
Bathroom Fitting- 26 Feb 2026
Worst job ever. The first day he came at 10.30am started the job left at 9pm said it would take a day & a half. The next day he said he would be here at 8.30am again he came at 10.30am & his words were I’m going to finish in 2 hours maximum. By 3pm he still hadn’t finished & I heard him speaking to someone on the phone saying that he would be there in 45 minutes.then he told me he needed a part for my job & he would be a couple of hours, he came back 4 hours later without a part.Again he was here till 9.30pm. He said he had finished. I went to look and his work was bad. I complained he said he would come back the next day. the next he said he had finished & I told him I wasn’t happy he came back the next day. He tidied up his mistakes.he shaved the bottom of the door off a bit as it wouldn’t close coz of the new tiles & he left, as he was leaving he said please give me a good review. I said I’ll tell the truth & he said but the truth isn’t good. He didn’t stick the threshold back on.
AVBase Building Services London Limited
No reviews yet
Extension Builder in St James
Avbase Building Services London is an award-winning family business with a deep-seated commitment to transforming homes. With over 20 years of experience in the construction and home improvement industry, we specialise in creating additional space with bespoke house extensions and loft conversions, designed to your unique requirements. Our comprehensive services include meticulous design, thorough planning, and efficient build processes, ensuring a seamless experience from the initial concept to the final touches. Our expertise includes side return projects, offering creative solutions to utilise every inch of your property effectively. We are proud to be known for our reliability, attention to detail, and the impeccable cleanliness we maintain throughout our projects. Serving London, we are committed to turning your house into the home of your dreams.
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F&U Building Construction
Rating: 4.7 out of 5
Extension Builder in St James
All aspects of building work covered professionally. Always willing to go the extra mile. Very low prices. * Extensions/ Conversions. * Full kitchen fitting. * Full bathroom fitting. * Painting/ wallpapering. * Chimney removal. * Plastering. * Tiling. * Double glazing/bifolds. * All Diy handyman works Covering Barking, Dagnem, Romford, Ilford, Gant's hill, Leyton, Leytonstone, Walthamstow, Woodford, all areas in East London, please ask.
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Latest review:
Carpentry- 10 Oct 2022
Athar and his team did a brilliant job to a very high spec with a good price. I am very happy with work done. Would highly recommend
Paintworks
No reviews yet
Extension Builder in St James
We are a trusted painting, decorating, full house extension and loft conversion company dedicated to transforming homes with precision, creativity, and exceptional craftsmanship. With a strong focus on quality and attention to detail, we deliver complete property improvement solutions that enhance both the beauty and functionality of your space. From flawless interior and exterior finishes to bespoke house extensions and expertly designed loft conversions, we manage every stage of the process with professionalism and care. Our experienced team works closely with clients to understand their vision, ensuring every project is completed on time, within budget, and to the highest standards. We pride ourselves on reliability, clear communication, and a commitment to exceeding expectations. Whether you’re refreshing a single room or expanding your entire home, we provide results that add lasting value and style.
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House Doctor Services
Rating: 5 out of 5
Extension Builder in St James
House Doctor services is a new business operating in London,Berkshire and Bedfordshire. We are a team of 3 people with 7 years experience in demolition, painting and decorating, tilling,kitchen fitting, flooring,gardening. We are growing each day, with new clients added each week. Our clients are our friends so we treat everyone like family. we are available 24/7, we offer free quotes on all the jobs. Give us a try today.
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Latest review:
Demolition- 3 Sep 2020
Happy to recommend - completed the job very quickly and cleared up tidily after themselves.
NexLevel Contractors Ltd
Rating: 5 out of 5
Extension Builder in St James
We are a small, family owned, London based building company with an excellent reputation for workmanship and customer service. Our people hold many trade specific accreditations such as Gas Safe Register and NICEIC and should give you the comfort that you are dealing with professionals. We are accredited by the of Federation Of Master Builders & full members of TrustATrade. With a team of qualified professionals we offer a complete service for all of your domestic & commercial needs.
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Latest review:
Restoration & Refurbishment- 11 Jan 2018
Dorian Lula and his team completed in excellent terms full flat renovation. Dorian is very accommodating and his communication is fantastic as we didn’t have any misunderstandings ... I am glad I have met him and for sure I will be keeping in touch for my next project. Special thank you to this site for this fantastic opportunity as I feel I got a very good deal Yours truly Violeta Ku
BDS TM Limited
Rating: 5 out of 5
Extension Builder in St James
FULL REFURBISHMENT ,HOUSE EXTENSION AND LOFT CONVERSION SPECIALIST,PAINTING, ELECTRICAL&PLUMBING
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Latest review:
Electrical- 18 Apr 2020
Ben fixed my lights and electrics in garden. He took his time and was punctual. Hes very helpful and resonable. i was very happy with his work, i would recomend him to anyone what a nice man.
RABII
No reviews yet
Extension Builder in St James
carpentry/plumbing/painting/masonry work
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singhbuilder
Rating: 5 out of 5
Extension Builder in St James
Hi my name is Dil Singh, I'm a runing own business with 10years + experience, Multi skilled in all aspects of as a certified electrician, roofing and building.Able to deliver a high standard of work. All new work can be done guaranteed,References avalible on request. I done plenty jobs like electric work: change the consumer unit, wiring, design and inspection and testing, fault finding, loft conversion, extensions. I never let down my customers. Job done guaranteed from a to z by me.
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Latest review:
Electrical- 26 May 2021
Happy with replacement programmer. Dil came straight back the next day when there was a problem and rectified.

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.