Extension Builders in Belsize

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.1 (18 reviews)

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Some of our top rated extension builders in Belsize

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Home Renovations Ltd
Rating: 5 out of 5
Extension Builder in Belsize
We're a building company specializing in house extensions, loft conversions and refurbishments. Our clients come from New Malden, where we're based, but also surrounding areas. The vast industry experience enables us to provide valuable advice, professional services and individual approach, benefiting our customers. As we understand trust and credibility are crucial when undertaking such projects, we arrange viewings and provide customers with references and photos of our most recent projects.
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Latest review:
Extensions- 24 Jun 2017
We had a large piece of work done by Johan and his team. It was a 4m single storey rear extension with new kitchen installation, converting the old kitchen into a downstairs bathroom and utility room, plus other bits and bobs like new boiler, rear patio. We got quotes from a few builders, Home Renovations weren't the cheapest, they were actually towards the higher end. But we went and saw their previous work and spoke to some of their other clients. The work was done to a high quality and the clients seemed to be happy so we decided to go with them. Johan's team are very hard working, professional and polite. Pawel and his team of builders, bricklayers, plumbers, electricians, etc. would turn up before 8am and finish at 6pm working solidly throughout the day. There is Magda as the project manager who keeps you in the loop, and answers any of your questions (which we had many). There is Michaela on the finance side who keeps you up to date with the budget. Our budget went over by 5% with "variations" (extra work or materials) but it was always communicated why and the work wasn't done without our approval. Pawel would give his recommendations but the final word would always be ours. But these things can add up. Overall we were very happy with the build, it was done to a very high standard. They also finished it before time. They said it would take 12 weeks in fact they finished it in 10 weeks which was amazing as you would normally expect these things to go over.
N&D Brickwork Construction
Rating: 5 out of 5
Extension Builder in Belsize
Over 17 years experience doing all building work, building houses, extensions, garden walls and paving. Customer guarantee satisfaction
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Latest review:
Extensions- 1 Jul 2021
Great job done by Naim and his team. He expressed interest in the job as soon as I posted. If it hadn't been for some wet weather the job would have been completed much sooner in the timescale he quoted. There was one small issue some time after the job was completed. I only called Naim once and he arranged a day to come fix it. We're very pleased with the finish, we would give future work to him and also recommend him to friends & family.
GH Build Specialists
No reviews yet
Extension Builder in Belsize
NvQ level 6 construction manager with 20 years construction experience.
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Portclean Services Solutions Ltd
No reviews yet
Extension Builder in Belsize
At Portclean, we specialize in a wide range of cleaning and professional services to meet your needs. Our offerings include: Office Cleaning: Our expert team provides consistent, top-notch cleaning services to keep your office spaces immaculate. We tailor our approach to fit your schedule and requirements, ensuring a clean and productive work environment. End-of-Tenancy Cleaning: Experience the power of our thorough deep cleaning services. Whether you need a fresh start in a new space or want to leave your rental property spotless, we deliver exceptional results that exceed expectations. Builders Cleaning and Handyman Services: Trust our skilled professionals to handle all aspects of post-construction cleaning and general maintenance. We tackle debris removal, dusting, repairs, and more, providing comprehensive solutions for a pristine workspace. With years of 15 experience, a dedication to quality, and a commitment to customer satisfaction, Portclean is the trusted choice for all your cleaning and handyman needs. Contact us today and discover how we can elevate your workspace with our unique and professional service
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Ad construction
Rating: 5 out of 5
Extension Builder in Belsize
Loft conventions ,new extensions, plumbing, painting, tiles, planning, renovation, electrical I have lots of experience on this types off the jobs , I will finish all the jobs on time , with guarantee inside and outside of the ,
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Latest review:
House refurbishment, plumbing, plastering, painting, electricity, building shed, kitchen fixing. He is one of the best builders. I would recommend him.
Igorotplumber and building services
No reviews yet
Extension Builder in Belsize
Hi I've been in the industry for more than 15 years . Reliable and friendly. No small and big job.
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Mirma Construction Ltd
No reviews yet
Extension Builder in Belsize
Since 2016, with a commitment to quality and customer satisfaction, we have specialized in a wide range of services tailored to meet your project needs. From comprehensive general Building Works to specialized services such as Piling Foundations, Drone Survey and Mapping, and Civil Engineering, we bring expertise and reliability to every endeavour. At Mirma Construction, our dedicated team of professionals combines years of experience with cutting-edge technology to deliver outstanding results. Whether you're envisioning a new construction project, enhancing existing structures with house extensions, or transforming landscapes with our Soft and Hard Landscaping services, we prioritize precision and attention to detail. Our mission is to exceed expectations by providing sustainable, efficient, and aesthetically pleasing solutions that stand the test of time. We take pride in our ability to deliver projects on schedule and within budget, ensuring seamless collaboration and transparent communication throughout. Explore how Mirma Construction can turn your vision into reality. Contact us today to discuss your next project and discover why we're a trusted partner in construction innovation.
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AKAM BUILDERS LIMITED
Rating: 5 out of 5
Extension Builder in Belsize
Akam Builders have over ten years experience in providing cost effective solutions for domestic & commercial building requirements be it simply refreshing an old bathroom to building a nursing home. We have a hard working team ready to help you transform your house into your dream home.
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Latest review:
I had a commercial property converted into 2 one bedroom flats. Akam builders did an A-class job. The work was done to a very high standard and within the time scale stated by Gurwinder. I was impressed by the extra work he did without any extra charge. This builder is a genuine and reliable builder. The work is in perfect condition after 6 months.
Robert Bielat
Rating: 5 out of 5
Extension Builder in Belsize
I am a 44 year old qualified plumber and Gas Safety engineer. I have 14 years of experience in the UK alone. I will offer appropriate advice before undertaking any work, and I always stay as long as it takes for the job to be done properly. I am also happy to work as part of a team if needed.
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Latest review:
Central Heating- 23 May 2016
I hired Robert to remove a radiator and do a boiler service. Rob did a good job and was punctual. He also took the time to explain what he was doing and why he was doing it. I would hire him again.
Plumber
No reviews yet
Extension Builder in Belsize
Hi my name is Gledis. I am a plumber, also I am very good at landscaping, flooring, extensions, bathroom fitting, painting and gardening. I have a lot of experience on the construction industry, also I do a bit of carpentry (installing doors, partitions etc) I am always on time, very good at communicating and understanding whats the budget of the costumer and knowing what they want.
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ND constitution
No reviews yet
Extension Builder in Belsize
We have our own company name ND construction we have done job building whole house which includes everything that comes in building work , question I might failed because of language issue but I would recommend you to come on our site to inspect our work thanks
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Iron Handyman
No reviews yet
Extension Builder in Belsize
33 years of experience, before this experience, I both worked and studied in all construction works (water, electricity, tile, gas, paint, etc.). I have been skillfully doing carpentry, which is a father's profession, from childhood until this time. The works I will do will be the best proof.
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Skyline renovating ltd
No reviews yet
Extension Builder in Belsize
Welcome to Skyline Renovating Ltd. We specialise in renovation, construction, and development. We cover areas London and East Sussex.Our experienced team delivers high-quality projects on time and within budget. Whether updating your home or building new structures to developing properties, we bring your vision to life. Trust us to handle all your construction needs with professionalism and excellence.
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Mapna constraction ltd.
Rating: 4.2 out of 5
Extension Builder in Belsize
Hi everyone, We are a family-run business with over 10 years experience and pride ourselves on our incredibly high-standard quality of work, customer rapport, competitive prices and efficient time-frames. With our customers' satisfaction held in the heart of our work, we will go the extra mile to ensure all needs and requirements are met and you are 100% satisfied with the end product. 'If it isn't good enough for our home, then it isn't good enough for yours'.
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Latest review:
Bathroom Fitting- 8 Apr 2026
Arash and the team were great - on the job on time every day - flexible in regards a lot of the fittings and adjustments. Very good price and work completed on time. Monies all agreed upfront, payment in part as based on progress. Will use again.
Z3 Construction ltd
No reviews yet
Extension Builder in Belsize
We understand that construction is more than just building—it’s about creating spaces that are functional, durable, and perfectly suited to your needs. That’s why we take the time to plan carefully, communicate clearly, and work efficiently from start to finish. Whether you’re upgrading a single room, expanding your property, or starting a project from the ground up
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H-Build Limited
No reviews yet
Extension Builder in Belsize
After 20 years experience working for large contractors and developers; H-Build Ltd, has been formed to focus our experience and expertise in residential construction to work on smaller but more rewarding projects for individual clients/homeowners.
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4.1

Top rated Extension Builders

Our Extension Builders in Belsize, are rated 4.1 out of 5 based on 18 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 Belsize?

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 Belsize 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 Belsize who are available and interested can respond to your post.

Browse profiles, read customer reviews and get quotes from your chosen Belsize extension builders, all before you decide who to hire.

What are the hourly rates of extension builders in Belsize?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Belsize 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 Belsize extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Belsize home extension project is likely to cost.

Find extension builders in Belsize with MyBuilder

Hiring the right extension builder in Belsize 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 Belsize extension builders. Once your job is live, we’ll share it with home extension builders in Belsize who can express their interest.

Step 2: Compare different extension builders in Belsize

When you start receiving interest, review profiles of local Belsize extension builders, check their previous work, and read real customer reviews. Ask about timelines, materials, and request detailed quotes.

Step 3: Hire Belsize extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Belsize, 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.

Belsize extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Belsize extension builder before hiring?

Before hiring an extension builder in Belsize or extension building company in Belsize, 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 Belsize?

An extension builder in Belsize 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 Belsize 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 Belsize?

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 Belsize 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 Belsize 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 Belsize

Can an extension builder in Belsize help with planning permission?

Yes, many extension builders in Belsize 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 Belsize handle everything from design to construction?

Many Belsize 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 Belsize help with materials and finishes?

Yes, most extension builders in Belsize 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.