Extension Builders in Harrow

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.9 (15 reviews)

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Some of our top rated extension builders in Harrow

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Marangoni Construction
Rating: 5 out of 5
Extension Builder in Harrow
We are dedicated to building quality projects and our wealth of experience and efficient working methods mean that with us on board, you get more - more choice, more cost savings and a quicker turnaround.We are a hard workers,good organiser,sociable,loyality,honest
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Latest review:
Hard working and experienced professional with large experience in mid-sized residential projects. Dyone always tries to go the extra mile to please the client. He has worked in several European countries giving him access to better knowledge of materials and suppliers. Great to work with.
R KELLS LTD
No reviews yet
Extension Builder in Harrow
Hello, and welcome! I’m Rkan the owner and lead builder of R KELLS LTD . With years of experience and a commitment to exceptional quality, I’m proud to be known as one of the best builders in London. Whether you’re looking to renovate, extend, or start a completely new project, I bring both expertise and passion to every job. I work closely with my clients to ensure that their vision becomes a reality, on time, on budget, and with the highest standards of craftsmanship. My focus is always on providing a hassle-free experience and delivering outstanding results. Let’s create something amazing together!
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Alex Deco Design LTD
Rating: 5 out of 5
Extension Builder in Harrow
Alex Deco Design Limited is a family run business with years experience and expertise in the construction and decorating field. Our team of decorators could undertake any residential or commercial job doesn't matter how small or big it is. Our team of builders could undertake any refurbishment, loft conversions, extensions. We will start and finish any job to the desires of your choosing.
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Latest review:
Plastering- 7 Apr 2018
Great Guys Thanks for your swift quality work .
Ceca Developments LTD
Rating: 5 out of 5
Extension Builder in Harrow
Hael Construction Ltd, a proud member of the Federation of master builders, is a trusted construction company based in North London, delivering high-quality building services across the region. We specialise in new builds, extensions, loft conversions, renovations, groundworks, electrical installations, and plumbing. With a skilled team of qualified tradespeople and experienced project managers, we provide a complete service from design to completion. Our focus is on quality workmanship, transparent communication, and delivering projects on time and within budget.
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Latest review:
Extensions- 23 May 2022
Ceca Developments have done an outstanding work on our side and rear extension project, and we would definitely recommend this company. Firstly, they have offered a really competitive quote for the work and have been very transparent and detailed in regards to how long it will take to complete the project. Sebastjan has been a pleasure to deal with and was very helpful during the project, providing honest and useful recommendations and being available every time we needed anything. All the work has been completed to a very high standard and to the agreed timelines. We did not have to worry about anything during the whole project, which made this a very pleasant experience.
Soraya Construction Ltd
Rating: 4.2 out of 5
Extension Builder in Harrow
I am running construction projects for over 25 years. My projects include: construction houses, extensions, lift conversion, comercials, external and internal renovation, pavements.
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Latest review:
Restoration & Refurbishment- 28 Apr 2024
I highly recommend these people if you want to be fleeced, taken advantage of, treated appallingly and work left unfinished. The standard of work is below average. If you want high quality finishing do not come here. I’ve had to spend a lot to redo a lot of their mistakes and mess. If Jerzy could charge you for every single nail he would, so beware. And when you challenge, they get aggressive and nasty. Very unprofessional. Do yourself a favour and keep away. So thanks Jerzy and co for a load of stress and rubbish. I am happy to talk to anyone and advise against these people.
Corlona Ltd
No reviews yet
Extension Builder in Harrow
Here at Corlona, we have a professional team of tradesmen with many years experience of working on domestic and commercial projects of all sizes. I have over 25 years experience in the building industry, working on many different types of projects. The type of work we normally undertake, is the refurbishment and extension of properties.
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Naksh construction ltd
Rating: 4.2 out of 5
Extension Builder in Harrow
We are a highly skilled, competent, and professional team of builders at Naksh Construction Ltd. We offer all the building services you could require, including additions, new construction, basement conversions, new residential or commercial construction and renovations of your existing bathrooms, kitchens and residences. Not only do we complete this task quickly and professionally, but we also take care to ensure that every job we complete is sophisticated, elegant, and meets your demands and specifications."
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Latest review:
Extensions- 7 Apr 2025
Quotes were provided and the job was agreed upon. The project involved a full house restructuring and extension build. However, after several stages of work, communication with Jas was lost, and his co-worker took the lead on site. Several issues arose, such as recommending smart plumbing equipment for purchase, but their plumbers were unable to install it. The tiling, skirtings, and tiles were not completed. Tiles around the columns were cracked. After Jas's team abandoned the project, another plumber had to install all the remaining items. The job was left unfinished, and we had to find alternative contractors to complete it. Significant time and money were wasted due to persistent communication problems, failure to issue invoices, and numerous other issues. Eventually, Jas and his main labourer stopped responding and disappeared, ignoring phone calls and WhatsApp messages. Be aware of these potential issues.
Arisha services ltd
Rating: 5 out of 5
Extension Builder in Harrow
I am gas safe register by qualification, and undertake most of heating and plumbing jobs. Which can be megaflo, new installation of boilers and repairs. I have skills to lay any type of floorings. I have been in the trade over 6 years and take on extention, conversions of lofts, renovations, bathroom, kitchens, tilling, skimming, painting. I can do decking, polycarbonated sheets, glassfiber roofs, sheds, screeding, concreting. I would cover most of building work.
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Latest review:
Good manners and workmanship I will definitely use your services again Thanks Man
Dipesh
No reviews yet
Extension Builder in Harrow
Hello! My name is Dipesh, and I have over 11 years of experience as an electrician and security system fitter. Throughout my career, I have developed a strong expertise in ensuring the safety and efficiency of electrical systems and security installations. In addition to my work in electrical and security systems, I also offer top-notch handyman services and possess excellent skills in building outbuildings. Whether you need assistance with repairs, installations, or custom construction projects, I am here to help. I take pride in delivering high-quality workmanship and exceptional customer service, ensuring that every project is completed to your satisfaction. I look forward to working with you and providing the solutions you need for your home or business!
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enrike
Rating: 4.9 out of 5
Extension Builder in Harrow
Mani Buildworks Ltd is a trusted leader in the construction industry operating since 2015 offering high-quality services for residential, commercial, and industrial projects. With a commitment to excellence, safety, and sustainability, we provide tailored solutions that meet our clients’ unique needs. Our experienced team is dedicated to delivering projects on time and within budget, while maintaining the highest standards of craftsmanship and customer satisfaction. At Mani Buildworks Ltd , we build with integrity, innovation, and a focus on long-lasting results.
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Latest review:
Plastering- 15 Oct 2018
Enrike plastered my mums hallway and gave her a good price for the work,was reliable and did a good job.
LQ Construction
Rating: 5 out of 5
Extension Builder in Harrow
Based in North London and with over 18 years of experience in the construction industry, LQ Construction specialises in bricklaying, renovations, and paving services, offering our clients high-quality, reliable solutions to their construction needs. Committed to delivering excellence in every project we undertake., the extensive experience have equipped us with the expertise to handle a wide range of projects with precision and efficiency. We take pride in our craft and approach each project with a commitment to integrity, reliability, and meticulous attention to detail. Whether you're embarking on a major renovation or need professional bricklaying or paving services, we ensure your project is carried out to the highest standards, on time and within budget. Explore our website to learn more about our services and how you can trust LQ Construction to help bring your projects to life.
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Latest review:
Bricklaying- 11 Jul 2025
Landi was excellent. Finished the job to a good standard
MARCIN'S CONSTRUCTION LTD
Rating: 5 out of 5
Extension Builder in Harrow
Marcin’s Construction LTD is a professional building and refurbishment company delivering high-quality residential renovation services across London and surrounding areas. We specialise in full property refurbishments, kitchen and bathroom renovations, and interior works. Our focus is on clear communication, detailed written quotations and a clean, well-organised finish on every project. With over 10 years of experience, we work with homeowners, landlords and property investors, providing a structured and reliable service from initial discussion to project completion. Every job is carefully planned, carried out efficiently and completed to a high standard. Additional information about our work and recent projects is available on our company website.
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Latest review:
Extensions- 7 Oct 2025
I cannot recommend Marcin and his men more. They were immensely helpful throughout a difficult (due to my inexperience and space and budget constraints) and rushed project. They worked to my budget and schedule and delivered to high quality - really an unbelievable job. If you choose them, you are in good hands. They are honest, reliable, and trustworthy.
PEPOSHI
No reviews yet
Extension Builder in Harrow
Carpenter
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Angle Construction
Rating: 4.7 out of 5
Extension Builder in Harrow
We have been in the construction business for over 15 years doing all sorts of works, from minor works to full home constructions. No job to small no job to big. We work in and around London
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Latest review:
Windows & Doors (uPVC & Metal)- 28 Jan 2026
Very unhappy with how things went with Angle Construction overall. Poor comms during the transaction was the first red flag - no communication for 2 days the moment money was sent, however afterwards received an apologetic call - parts ordered and arrived in due course. Andrei turned up, and got to work on removing the old gate, but then started shaving down the post without saying anything -we were told after that the posts were not level. Eventually he said the door would need to be cut, which we agreed to. The door and posts were both cut to fit, but massive gap left at the bottom, and only half of the door fittings and no handles were installed! In addition, where the door was cut and the wood shaved made, a lot of mess was left all over the garden furniture and patio floor. Shocked at the lack of care and professionalism. He was clearly agitated and in a rush to leave. We have a working back door, but it looks like a real botched job. Not happy, and I would not recommend.
Kupa
Rating: 4.7 out of 5
Extension Builder in Harrow
Hello.We have experience on gardening,groundworks ,excavation#block paving#lawnmowing#fence panels#everything about construction. We offer quality work#great prices#great service#(Reinforcement underpinning) working ten years for company.
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Latest review:
Garden Maintenance- 18 Oct 2025
Highly recommended. Quick, efficient and offered a competitive quote. Will definitely use again!
David Adrian Samfira
No reviews yet
Extension Builder in Harrow
Hello my name is , David I have experience in construction from more then 20 years . I do decorating walls like Venetian stucco limewash paint and also media wall . Extensions tilers House rendering microciment
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3.9

Top rated Extension Builders

Our Extension Builders in Harrow, are rated 3.9 out of 5 based on 15 reviews from customers like you.

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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.