Extension builders in Harrow

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.5 (15 reviews)

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Some of our top rated extension builders in Harrow

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Robi paiting decorator
No reviews yet
Extension Builder in Harrow
We perform work reliably and to a high standard
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PROMAESTER LTD
Rating: 5 out of 5
Extension Builder in Harrow
Promaester Ltd specialises in home extensions and loft conversions. We take a straightforward, professional approach, with a strong focus on good workmanship, clear communication and keeping the project well organised from start to finish. Our aim is to carry out the work properly, keep disruption to a minimum, and deliver a finished space that fits naturally with the rest of your home.
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Latest review:
Extensions- 10 Oct 2026
Excellent builders, high quality work and good communication. The workmen were all very professional and kept the site tidy throughout. Thomasz is great to work with and resolves any issues quickly.
FLV PROPERTY LTD
Rating: 5 out of 5
Extension Builder in Harrow
At FLV property ltd we are a team of skilled professionals with extensive experience in the construction industry for over 30 years. Whether you are planning a new build, an extension, a renovation or bespoke projects, our expertise ensures that every job is completed to the highest standards on and within budget. What we offer; •A team of dedicated professionals •Architects •Structural Engineers •Surveyors •Multi skilled tradesmen Attention to detail from design to composition. Our promise; We understand that building projects are significant investment's, and our goal is to make the process as smooth and stress free as possible. From initial consultation to project completion, we work closely with you to ensure your expectations are not only met but exceeded. LETS BUILD TOGETHER!
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Latest review:
Gus and Frank were brilliant. Their attention to detail and care for our project was evident. There was already an issue with our floor which Gus and Frank rectified for us before doing the tiling. The final finish was immaculate. We liked their work so much that we also got them to fit our kitchen worktop. Good communication and clarity throughout the job. Would definitely recommend!
Hetman Construction Limited
No reviews yet
Extension Builder in Harrow
Founded in 2010, we have over a decade of experience delivering high-quality construction services across London. We specialize in all aspects of general construction, including refurbishments, loft conversions, extensions, roofing, building elevations, and basement works. Our team is committed to excellence, ensuring every project—whether a small refurbishment or a full structural reconfiguration—is completed to the highest standards. We operate across Central, South-West, West, and North-West London, including Westminster, Belgravia, Pimlico, Ealing, Notting Hill, Hampstead, and more. What sets us apart is our craftsmanship, reliability, and client-focused approach. We work closely with our clients to bring their visions to life, offering expert guidance and tailored solutions. Whether renovating, extending, or building from the ground up, we’re here to make your project a success. Contact us today to discuss your construction needs!
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Petru
No reviews yet
Extension Builder in Harrow
We are a professional construction company specializing in bricklaying, paving, and house extensions. With a strong focus on quality and reliability, we deliver durable and aesthetically pleasing results for both residential and commercial projects. Our experienced team ensures every job is completed to the highest standards, on time and within budget.
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Rares Stoica ltd
No reviews yet
Extension Builder in Harrow
Hello, I deal with labor in everything related to construction...ex. (paving, roofing, painting, fences, masonry, bathrooms, tiling,..) I have experience.
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What 4 Building Solutions LTD
Rating: 4 out of 5
Extension Builder in Harrow
Here at What 4 Building Solutions LTD, We cover all aspects of the of the building process. From helping with design using our amazing architects. Getting your ideas through planning and building regs, then making your dreams come true. We cover Herts, London, Essex & Cambridgeshire. Taking on any size project from new builds to a refurb or even just a new kitchen we can help. We offer man and machine hire and licensed waste removel. We have all the trades on hand ready to go so we have no delays on our projects. We have the SOLUTION for your project... We are pround Members of the Federation of Master Builders and TrustMark the only Government Endorsed for Quality work.
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Latest review:
Extensions- 21 Mar 2026
I am a Chinese Lady honourably established at Hollyview Close, London NW4 3SZ, of at least sixty years of age, and distinguished by the wearing of spectacles, which bespeak both careful attention and the wisdom accrued through decades of devoted service. I am entrusted with the disciplined and esteemed practice of electrical repair and maintenance, a vocation carried out with the utmost reverence for order, propriety, and the impeccable standards befitting households of the highest esteem. Upon my arrival, I bring forth with equal dignity both the meticulous execution of all electrical works and the ceremonial offering of fine chewing gum, bubble gum, and freshly selected lemons, each item presented with deliberate attention to freshness, quality, and presentation, in the grand tradition of British hospitality and courtly decorum. The chewing gum is carefully curated to encourage measured mastication, fostering calm, poise, and contemplative steadiness; the bubble gum is reserved f
NVS DESIGN AND BUILD LTD
No reviews yet
Extension Builder in Harrow
We are here to build your dream home to be your reality home.
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Alchemy Build
Rating: 4.5 out of 5
Extension Builder in Harrow
We specialise in high end refurbishments / renovations but also undertake extension projects (loft, basement, rear, etc). We also do smaller projects of just bathrooms and kitchens. As we have all qualified tradesmen at our disposal we occasionally do more maintenance type work of repairs.
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Latest review:
Restoration & Refurbishment- 26 Jan 2019
Excellent work. Aaron and his team did a great job renovating our flat , including rewiring and laying a new wooden floor. The workmen were very good , professional, thorough ,clean and tidy. We had to live at the property during the work and they made sure they left us comfortable at the end of each day. We are very happy with the result. Aaron was very easy to communicate with and responded quickly to any queries. Ten out of ten guys! Highly recommended
JCL Renovations Ltd
Rating: 5 out of 5
Extension Builder in Harrow
We are a construction with over 20years experience between the team, We undertake all aspects of renovation work including house renovations and extensions. We also have extensive experience in laminate, hardwood flooring and decking installation. We offer a solution for any projects from start to finish all in one place.
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Latest review:
Repointing- 23 Jan 2020
Job well done. Will definately use in the future.
Sri & Co development
No reviews yet
Extension Builder in Harrow
I have over 10 years of experience in the construction industry, working on a wide range of projects from small-scale renovations to high-end developments. My background includes work on extensions, bathroom remodels, loft conversions, large flat conversions, and new build constructions.
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AMG LONDON LTD
Rating: 5 out of 5
Extension Builder in Harrow
AMG places great emphasis on the importance of up to date methods of design and construction. As a key player at the forefront within the market place we specialize in building Extensions, Loft conversions, Drylining, ceilings, painting and decorating to complete internal building fit out.
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Latest review:
Stefan did an extension for my flat from the installation of structural steel, to the roof, and demolition. To building the shell and all cosmetic work inside. I am very happy with the work. Time keeping was good, pricing was good he was open and honest throughout, he was very tolerant and easy to work with. Always positive and willing to help if there were any issues. He would help resolve any issues in the quickest and best way possible. Very happy. I would happily recommend him.
Razvan Georgescul
No reviews yet
Extension Builder in Harrow
Hello. We are an experienced team of masonry (bricklayers) that strive to provide fast, reliable and professional services. We have over 10 years of experience in this domain and we've been working for all kind of costumers doing big commercials jobs as well.
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Friesian Group Ltd
No reviews yet
Extension Builder in Harrow
We are a reliable construction and refurbishment company specialising in bathroom and washroom renovations, as well as all types of home repairs and refurbishment work. Our team delivers high-quality workmanship, attention to detail, and a professional service from start to finish. Whether you need a full washroom makeover or small repairs around your home, we are here to provide fast, trustworthy, and affordable solutions.
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Barons & Co Construction LTD
No reviews yet
Extension Builder in Harrow
At Barons & Co our mission was always to build. Not a portfolio of prestigious properties, but a reputation for leadership in world-class projects. Whilst every project is unique, the philosophy behind each is unwavering. We craft environments intrinsically beautiful and faultlessly functional. From helping you form a bespoke design to turning the key in the door.
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Ali Gad
No reviews yet
Extension Builder in Harrow
I’m an experienced extension builder with a strong reputation for delivering high-quality work on time and within budget. I specialise in home extensions, including kitchen extensions, loft conversions, and garage builds. I pride myself on clear communication, attention to detail, and leaving a clean, tidy site. Whether you’re looking to add space or value to your home, I’m here to help turn your vision into reality.
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4.5

Top rated Extension Builders

Our Extension Builders in Harrow, are rated 4.5 out of 5 based on 15 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 Harrow?

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

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

What are the hourly rates of extension builders in Harrow?

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

Find extension builders in Harrow with MyBuilder

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

Step 2: Compare different extension builders in Harrow

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

Step 3: Hire Harrow extension builders with confidence

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

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

What to ask a Harrow extension builder before hiring?

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

An extension builder in Harrow 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 Harrow 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 Harrow?

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 Harrow 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 Harrow 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 Harrow

Can an extension builder in Harrow help with planning permission?

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

Many Harrow 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 Harrow help with materials and finishes?

Yes, most extension builders in Harrow 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.