Extension Builders in St James

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.4 (19 reviews)

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Some of our top rated extension builders in St James

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A1&PM Ltd
Rating: 3 out of 5
Extension Builder in St James
In our focus, we are interested in customer satisfaction, we provide guaranteed quality, we have the capacity to start work for the customer when he wants it at any time, and undoubtedly we have the most competitive prices in the market A1&PM is your home company, we are ready at any time, for any type of work and at any price, we will do your work
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Latest review:
Bricklaying- 28 Jan 2025
I recently hired A1&PM to carry out structural repairs on my house, including replacing window lintels and providing complex temporary works to support the structure during the repairs. They also patched plaster, skimmed a wall, rendered, and repointed an external wall. From start to finish, the team was professional and reliable, turning up on time with all the necessary tools and materials. Protecting carpets and covering furniture. Their knowledge and expertise were evident throughout, and they completed the work exactly as promised. The pricing was very competitive, and the quality of the work exceeded my expectations. I was initially sceptical due to some past review, but my experience couldn't have been better. I would definitely use their services again and wouldn't hesitate to recommend them to others. Fantastic work—thank you!
Don & Dorian Limited
Rating: 5 out of 5
Extension Builder in St James
We are Don & Dorian Limited. We are a family run business based on the corner of Central London in Islington. We have a combined experience of 40 years between us. We specialise in interior renovations, loft conversions, extensions and new builds. We usually undertake a project fully from start to finish as we have many in-house trades from plumbers and electricians to carpenters and painters. We pride ourselves with the quality of work we produce and thoroughness.
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Latest review:
Extensions- 17 Feb 2022
Don and Jake were terrific. Nothing was too much trouble and they provided work to a very high standard. They were extremely competent and I cannot recommend them highly enough. I have done many building projects and they were the first builders that I didn't fall out with!
Regal Construction Services Ltd
Rating: 5 out of 5
Extension Builder in St James
Free Viewing & Quotation Contact us to arrange a free viewing by one of our managers. After the viewing, all the information obtained will be handed to our Quantity Surveying team, who will assess the extent of the work and produce a detailed Quotation, including a full break down of labour, materials and plant. This will be sent to you via email for your perusal. If you are not happy with any aspect of the quotation, we can arrange a second visit and go through the quote with you.
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Latest review:
Conversions - General- 3 Aug 2021
Regal have been absolutely brilliant. They carried out the work professionally and to a very high standard. The willingness to go the extra mile was greatly appreciated and we will be using Regal for all our projects going forward. Could not recommend them highly enough!
B&CE CONSTRUCTION LTD
Rating: 4.9 out of 5
Extension Builder in St James
I am versatile carpenter with a background in residential, commercial, and municipal construction and remodeling. With a strong foundation in carpentry and woodworking, I have expertise in framing, trim, windows, doors, and siding. I possess in-depth knowledge of the construction process, from material selection and techniques to tools and equipment.
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Latest review:
Carpentry- 14 Apr 2026
Great
LDN Construction
Rating: 4.6 out of 5
Extension Builder in St James
With over 20 years of experience, we specialise in loft conversions, roofing, extensions and more. We primarily operate in Greater London, Our team possesses diverse skills and knowledge, ensuring top-quality results. We take pride in delivering exceptional customer service, professional workmanship, and thorough aftercare. Choose us for your next project and experience the best in the business.
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Latest review:
Bathroom Fitting- 28 Nov 2024
in my place, everything looks fine. but they used long screws penetrated the downstairs pipeline, which made my life very hard, intense relationship with neighbors, neighbors tries to break in. and this problem is still going on. i don't know how to fix it.
Toma Construction Limited
Rating: 5 out of 5
Extension Builder in St James
I have over thirty years experience undertaken all type of building works including extensions, loft conversions, refurbishments and conversions. No job to big or to small.
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Latest review:
Groundwork & Foundations- 18 Dec 2020
Had three quotes for a base for a garden shed, Toma was the cheapest by far. We arranged a day for the work to be done, bit apprehensive because I never knew anything about the company. Mr Toma and two others turned up, what lovely people they were, especially Mr Toma, the job was highly professional, everything was tidied up. Would I use them again.........100%. I would highly recommend them.
RQ Brickwork
Rating: 5 out of 5
Extension Builder in St James
bricklayer, undertake new builds, extensions ,garden walls stone work and repointing
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Latest review:
Bricklaying- 21 Jul 2025
Really nice guy to deal with. Job was done on time, looks good. I will definitely work with him again and would recommend.
Sheila Build & Design Ltd
Rating: 4 out of 5
Extension Builder in St James
SBD Contractors was established in 2022, with roots firmly anchored in the vibrant city Central London. We provide comprehensive services that extend across all areas of Greater London. Our forte lies in orchestrating a symphony of simplicity, adeptly navigating the intricacies of acquiring, planning, designing, building, and harmoniously managing your properties. We specialise in transforming complexity into effortlessly straightforward processes, ensuring a uniquely smooth and tailored experience for you. Founded with the vision of offering clients a lifelong point of contact, we guarantee a simple journey and all the associated benefits throughout your property development and real estate experience. Our solutions redefine industry standards in property development, with a primary goal of simplifying the process for our clients. We ensure a hassle-free experience that saves you both time and money.
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Latest review:
Painting & Decorating- 9 Aug 2024
Sheila was very professional and she recommended a professional floor specialist part of her team who did a wonderful job. Will definitely use her services in the future!
ABETA GROUP LIMITED
Rating: 5 out of 5
Extension Builder in St James
ABETA GROUP LIMITED covers a wide range of construction services offered by our team of professionals.
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Latest review:
Kitchen Fitting- 30 Nov 2020
Aurenc was very helpful and accommodating. The work was well done. All the persons were respectful and clean.
First Int. Project Limited
Rating: 4.4 out of 5
Extension Builder in St James
Back on MyBuilder after 7 years !!! Design and build Architectural team Structural engineers team Build and construction Our business is based on TRUST | QUALITY | CARE Our company cover the following trades: -steel erecting - steel structures -roofing - loft conversions -plasterers - internal skimming -painters and decorators -kitchen installers -bathroom fitters -bricklayers - for extensions -landscapers -electricians -gas engineers -carpenters - floor, doors, structural -windows installers -bespoke furniture
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Latest review:
Bathroom Fitting- 15 May 2017
We hired Inside/Outside to re-do our bathroom. New sink, bath, toilet, tiles, lower ceiling, re-hang the door and move the radiator. They were polite, honest, professional and very hard working. When they came round to quote they were noticeably more thorough and showed more attention to detail than others. Their quotes were very competitive, their work was good and they removed all the rubbish as well. They also came back afterwards to check everything was working and to deal with a couple of 'snags'. We will be using them again.
Swift Building Masters
Rating: 4.9 out of 5
Extension Builder in St James
General Builder of over 40 years Experience. Carpentry & Joinery Background. I have worked on large and small Projects, Repair, Refurbishment, Extensions, Loft conversions and New-builds. Recently become a member of Federation of Master Builders. ALL WORK QUALITY ASSURED
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Latest review:
Extensions- 5 Nov 2016
Leslie carried out the following works: chemical damp injection to walls on rear extension, reroute down-pipe, repair fracture on rear wall, install gutter hedgehog. Hopefully, this will resolve some of the issues we had with damp, a blocked down-pipe and an overflowing gutter. Leslie arrived on time on the first day but was delayed a few hours the next day. However, the work still was done within two days as expected. Thank you!
Edward Fox Building
Rating: 5 out of 5
Extension Builder in St James
We are a family company in which we have been in the industry for over 20 years. We specialise in all aspects of construction such as renovations, loft conversions, new builds, and extensions. We like to give our clients affordable and competitor rates and work closely with the to insure the works and their ideas are turned into reality and make it as stress free them as possible.
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Latest review:
Restoration & Refurbishment- 31 Jul 2023
We put the ad up on Saturday morning, Ed popped over in the afternoon and gave us a quote and the job was completed on Monday! Super quick process. For a job that was causing us stress and we quickly realised we couldn’t do ourselves, Ed came in and sorted it really quickly as well as giving us advice on next steps for our redecorating. Will be contacting again when we need further help!
K&L Construction
Rating: 5 out of 5
Extension Builder in St James
We are a group of experienced contractors specialised in brick work, block work,tiling,rendering,plastering&decorating also in structure work,installing new beams, forming new floor levels & stud walls.We are more than happy to take on board all types,sizes & shapes of works & well prepared for a challenge.We as a team cover all building sector(BUILDING,PLUMBING,ELECTRIC,DECORATING,ALL IN ONE & MORE) so please don't hesitate to give us your trust and we promise you that we will deliver
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Latest review:
Conversions - General- 21 Jun 2025
Working with Petrit was a very pleasant and enjoyable experience. He and his team are friendly and open for discussions. They’re quick, affordable, and help with decision making. Would hire again! Have to say as well, as a woman, Petrit and his team treated my husband and I equally, unlike my experience with other tradesmen who direct all their conversations to the men. Petrit knocked opened up our living kitchen area, laid herringbone floors, replastered the property, installed new radiators, added a built in ladder to our attic, and re did our bathroom. He also helped us match the floor boards from an existing room and helped us source front and back doors for much better price than what we were getting quoted in East London. The painting of the entire house was done in a rush as we needed to move in, so the attention to detail fell down a little here compared to everything else that was done, but I wouldn’t hesitate to work with Petrit again!! After and before pics included!
First Choice Builders
Rating: 4.9 out of 5
Extension Builder in St James
Christopher Graham -Level 1,2,3 in Bricklaying Trowel Occupations. -NVQ Level 1,2,3 -Professional Development Diploma in Historic Building Conservation and Repair -Stone and Brick Repair for Historic Building Restoration -Building and Pointing with Lime Mortar In 2010 I started up First Choice Builders and haven't looked back since. Taking on all Bricklaying works, Fully Qualified with 15+ years experience. Have done extensive courses on Repointing and Brick Restoration. Mastering Tuck, Weatherstruck, Flush and all other types of pointing. Top quality brickwork guaranteed. Also have tower scaffold £150 per week hire. Which should save on getting a proper scaffolding which is a minimum of around £400. Please give me a call for a free quote.
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Latest review:
Bricklaying- 11 Mar 2026
Great Job by Chris, fairly priced and completed on time. Thanks
Em
Rating: 5 out of 5
Extension Builder in St James
Hey I’m Emrah professional builder for 6 years but my experience date way back. I do mostly refurbishments and maintenance. You can see some of my work below
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Latest review:
Conversions - General- 4 May 2025
I Hired Em to do my ground floor reno, which included a garage conversion and remodel of my kitchen where 2 internal walls were removed. Very glad I found Em to do the job. Him and his team was efficient, friendly, tidy and hard working. We encountered obstacles along the process (which is normal for any renovation) but Em gave his opinion, listened and we came to the best solutions. Very happy with the result. Em is a reliable, punctual, knowledgeable, fair, down to earth guy and one of the best if not the best contractor I have hired. Highly recommend. Some before and after pictures.
Design Build Deliver London LTD
Rating: 5 out of 5
Extension Builder in St James
Design Build Deliver London Ltd At Design Build Deliver London Ltd, we provide high-quality building and renovation services across London, delivering exceptional workmanship from concept to completion. With a strong focus on reliability, professionalism, and attention to detail, we work closely with homeowners and property developers to transform properties into modern, functional, and beautifully finished spaces. Whether it’s a full property renovation, a bespoke bathroom installation, or a complete extension project, our experienced team manages every stage with precision and care. We pride ourselves on delivering projects on time, within budget, and to the highest standards. Our Services * Full House Renovations * Bathroom Renovations & Refurbishments * House Extensions * Garden Design & Landscaping * Roofing Services * Plumbing Services * Electrical Installation & Repairs * Kitchen Renovations * Property Refurbishments * Interior & Exterior Improvements * General Building Works * Design, Build & Project Management Services Design Build Deliver London Ltd — transforming properties with quality craftsmanship and dependable service.
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Latest review:
Bathroom Fitting- 7 Jun 2026
Excellent service and outstanding workmanship! I recently had my bathroom renovated by this company and I couldn't be happier with the results. From start to finish, they were absolutely professional in every way. The quality of their work is truly perfect - they paid such close attention to detail and did an amazing job with everything. What's more, the price they quoted me was very reasonable and they stuck to it without any hidden costs or surprises. The whole process was smooth, efficient and stress-free. I would highly recommend them to anyone looking for building services - they really are top class and provide excellent value for money. Thank you for such a fantastic job! To Abdullah and his team.

4.4

Top rated Extension Builders

Our Extension Builders in St James, are rated 4.4 out of 5 based on 19 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.