Extension Builders in Harrow

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.8 (14 reviews)

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Some of our top rated extension builders in Harrow

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Dudzic Constructions
No reviews yet
Extension Builder in Harrow
Builders Company with 15yrs experience. Refurbishment and Construction .Maind thing Extantions Lofts and basements. We are very experienced team.Urs strength is Pestering on very high standard.
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Zen Construction
No reviews yet
Extension Builder in Harrow
I’ve been working in the construction and property improvement industry for over 12 years, gaining hands-on experience across a range of jobs from full house renovations to smaller repair and maintenance projects. I’m based in London and cover surrounding areas. I specialise in Demolition, Carpentry, Bricklaying, Laminate Flooring, Extensions, Driveways, with a strong eye for detail, reliable workmanship, and a focus on delivering high-quality results. I take pride in being honest, hardworking, and easy to communicate with—clients know they can trust me to get the job done right the first time. If you’re looking for someone dependable, skilled, and committed to quality, I’m ready to help.
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UK NAMA Constructions Ltd
Rating: 5 out of 5
Extension Builder in Harrow
Garden Fencing, Garden Decking, Artificial Grass, Wooden Floor Laminating, Decorating, Partitions.
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Latest review:
Carpentry- 28 Jan 2026
Ali did an exceptional job designing and building our staircase, and I couldn’t be happier with the result. From start to finish, he was a complete gentleman — polite, respectful, and a pleasure to deal with. Ali is clearly a true specialist at what he does. His knowledge, attention to detail, and confidence in his craft really stood out. He was able to design and install the entire staircase in just one day, which was genuinely impressive given the quality of the finish. He worked efficiently, kept the area tidy, and took great pride in his work. It’s rare to find someone who combines skill, professionalism, and good nature so well. I would highly recommend Ali to anyone looking for a high-quality staircase installed by a true expert.
HEATHROW build and design ltd.
No reviews yet
Extension Builder in Harrow
Looking to add space, comfort, and value to your home? I’m a professional builder specializing in home extensions—from extra bedrooms and kitchens to modern living spaces. I deliver custom designs, top-quality materials, and hassle-free construction. Every project is handled with care, attention to detail, and on-time completion. Let’s make your dream home a reality! Contact me today for a free consultation.”
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BG Lofts and Extensions LTD
Rating: 5 out of 5
Extension Builder in Harrow
I am an expert in construction & refurbishment for residential & commercial properties inc new builds. I undertake all kinds of work inc structural work, refurbishment, steel work, drainage, plumbing, electrics, loft conversions, kitchen installation, carpentry inc bespoke furniture & help with planning & design. By trade I am a carpenter, with 10+ years of experience where I have completed 100's of jobs. I am well priced with a very high standard of finish. References can be supplied on request
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Latest review:
Extensions- 14 Nov 2019
Bogdan himself is extremely knowledgable and his years of experience in industry is clear to see, which makes choosing him great value for money. Before and during the project he offered solutions that we hadn't considered and the would in fact save us money and be of benefit to us in the future. His team is punctual, reliable, diligent, speedy and clean! They take pride in their work which has led to a highly satisfactory work in the final build. Bogdan also has great connections to third parties (e.g. to flooring and curtains/blinds providers) which is very valuable, especially when trying to coordinate different aspects and timings of a full house redecoration. His quotes and payment structures are fair, clear and concise which is also very helpful. His communication is excellent too. All in all, Bogdan's great work took away a huge amount of stress during these projects. I would highly recommend Bogdan and his team for any prospective works someone is considering.
Oleg Yembryk
Rating: 5 out of 5
Extension Builder in Harrow
I've been working on various domestic & commercial projects for two decades.
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Latest review:
Oleg did an excellent job. Clear cost layout in quote. Was communicative through out the build so no hidden corners were cut. Any changes needed were clearly explained and any alteration easily accommodated. Very helpful with advice when needed. I would use him again and in fact would be my first choice.
Sky Builders1 Limited
No reviews yet
Extension Builder in Harrow
It is not your customer's job to remember you, it is your obligation and responsibility to make sure they don't have the chance to forget you. Hey Guy’s.. We are Sky Builders, always ready for you to make hardest task to easiest. We help you to make dreams into reality
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Clars Build Ltd
Rating: 5 out of 5
Extension Builder in Harrow
In collaboration with Trevi Home Ltd, a Surrey-based luxury kitchen, bathroom, and tile specialist, Clars Build Ltd is your top choice for renovation projects. Our skilled team, led by a 25-year-experienced Civil Engineer, offers: - Kitchen and Bathroom Design, Renovation, and Refurbishment - Loft Conversions and Extensions - Comprehensive Property Renovations Contact us today to create a more beautiful and functional home.
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Latest review:
1. Installation of new bathroom 2. Entrance hall, porch and living room plastering, painting, decorating and floor tiling 3. Electric work Laith’s team is hardworking, courteous and very skilled. Extremely pleased with the quality of work. The interior of the house has been transformed by the work and looks really great. Very pleased
Rajput construction
No reviews yet
Extension Builder in Harrow
We are experienced and reliable builders specialising in house extensions, structural alterations and refurbishments. We carry out all work to a high standard and in line with Building Regulations. We pride ourselves on being punctual, tidy and professional, with clear communication from start to finish. Fully insured and committed to delivering quality workmanship on every project.
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U & A Builder
Rating: 4.9 out of 5
Extension Builder in Harrow
We've been ground-workers for over 16 years now and we've got lots of experience. We specialise in many aspects such as groundwork, driveways, landscape gardening, underpinning, paving, foundations, extensions, fencing and general building work. Our jobs have a warranty and also guarantee to complete all jobs to a high standard.
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Latest review:
Landscaping- 19 Mar 2024
Completely professional from start to finish. Urim and Aryam are both excellent communicators, which made a huge difference in planning the drainage for our patio, and rebuilding our front steps. We had every confidence in them from the outset and they fulfilled all our expectations. A great team!
Lee s brickwork and landscapes
No reviews yet
Extension Builder in Harrow
I am honest reliable very highly skilled in bricklaying landscaping driveways turfing fencing and all paving been a bricklayer for 35 years and had my own company for 18 years
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Emit Zero Solutions Ltd
No reviews yet
Extension Builder in Harrow
Emit Zero is a London-based construction company delivering high-quality building and refurbishment services. Our team is dedicated to creating spaces that meet your needs, combining expertise with a professional approach. Our services include: • Home Extensions • Loft Conversions • New Builds • Structural Alterations • Insulation Installation We recognise that every project comes with its own unique challenges and opportunities. That’s why we take the time to listen, understand your goals, and work with you every step of the way. By blending thoughtful design, careful planning, and quality workmanship, we ensure every detail is handled with the care and attention it requires. Our team is fully insured, giving you peace of mind that your property is protected throughout the construction process. We also hold relevant accreditations in health and safety, ensuring that all work complies with current regulations and industry best practices. At Emit Zero, we don’t just construct buildings – we create spaces that reflect your vision and enhance the way you live and work.
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G&j
No reviews yet
Extension Builder in Harrow
I started my career as decorator in 2019 ,my goal is client satisfaction with a fair price and maintain the quality of my work which I intended to continue.
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synergic design studio
No reviews yet
Extension Builder in Harrow
My name is Sanjay Venkatakrishnan and I am an Architectural Assistant (Part 2) with a Master's degree in Architecture (RIBA Part 2) from the University of East London. I have extensive experience working with various architectural software such as Rhinoceros 3D, Autodesk AutoCAD, Autodesk Revit, Lumion, V-Ray, Enscape, and Adobe Creative Suite.
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Oak and stone construction
No reviews yet
Extension Builder in Harrow
We are a professional construction company specialising in building, refurbishing, painting, and decorating services. With a focus on quality, reliability, and attention to detail, we deliver projects for both residential and commercial clients, ensuring every job is completed to a high standard and on time. Quality building, refurbishing, painting, and decorating you can trust.
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Balbir Singh
No reviews yet
Extension Builder in Harrow
I have over 15+ years experience in the building trade. I am a reliable builder who operates in London and the wider area. I take great pride in all the work which I undertake, taking great care to make sure that my client’s needs are met in a meticulous and professional manner.
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3.8

Top rated Extension Builders

Our Extension Builders in Harrow, are rated 3.8 out of 5 based on 14 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.