Extension Builders in Harrow, Greater London

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, Greater London

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Angle Construction
Rating: 4.7 out of 5
Extension Builder in Harrow, Greater London
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.
Lead Renovations Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Refresh Renovations is changing the way the world renovates. Prioritising communication and transparency mitigates the pitfalls associated with stressful and poorly executed renovations. Our approach focuses on thorough planning and streamlined communication to deliver a stress-free and enjoyable renovation with fantastic results you can be proud of.
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Latest review:
Great work and very professional. Organisation and communication were top tier plus the finished work and tidiness were unmatched. 100% recommended.
Gat Construction Ltd
No reviews yet
Extension Builder in Harrow, Greater London
With over 15 years of experience in the construction industry, we provide high-quality craftsmanship and reliable service across a range of projects. As proud members of the Federation of Master Builders (FMB), we adhere to strict standards of professionalism and quality. We are fully insured with £5 million Public Liability Insurance and £5 million Professional Indemnity Insurance, giving our clients peace of mind. Whether it's small renovations or larger-scale builds, we deliver exceptional results with a commitment to safety and excellence.
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Building Project Group LTD
No reviews yet
Extension Builder in Harrow, Greater London
Building Project Group Building Trust with Quality Work We'll get the job done!
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DS Developments
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
My business is offering service in all the aspects of renovation, refurbishment and building work. My team is very reliable and respectful of our client's property. We work hard to make sure that all the work carried out is to the highest standards.
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Latest review:
Garden Maintenance- 17 Sep 2017
I hired DS Developments to completely landscape my small front garden. This involved clearing and levelling the area; moving and re-securing a bike shed; laying a patio and lawn; and a number of finishing touches. The area went from somewhat of an embarrassing eye-sore to an area of pride. One that several neighbours have already made compliments about. David provided a professional service from start to finish. His quote was more than I expected, but his knowledge and vision gave me the confidence to select his services. He provided a selection of options and stuck to budget; adapted well to new ideas/suggestions; and informed in advance where the cost would be impacted. He and his team also were as tidy and considerate as possible and I highly recommend their services.
Hertfordshire Brickwork Limited
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Hertfordshire Brickwork Limited., where quality comes first and competitively priced, too. 21 years experience constantly in that field of work. I pride myself on the outstanding quality and the great customer service I provide - that's a promise. It's one of many things I've been extremely proud of throughout my career. I also hold the highly recognised SMSTS Site Management Safety Training Scheme certificate so you can be sure everything will be well planned out safely and correctly. Kind regards, Danny Marsh
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Latest review:
Bricklaying- 14 Mar 2016
He completed the job - really impressed - Very Polite - he worked really hard and made a fantastic path for us. Highly recommend this guy.
Nova Building LTD
New on MyBuilder
Extension Builder in Harrow, Greater London
General Builder – Job Description for Quote I am an experienced general builder offering a wide range of construction and property improvement services. My work covers all aspects of building, from small repairs to full renovations, ensuring high-quality workmanship and attention to detail at every stage. Services include brickwork, plastering, carpentry, painting and decorating, tiling, flooring, and general maintenance. I take pride in delivering reliable, efficient, and cost-effective solutions tailored to each client’s needs. All work is carried out to a professional standard, with a strong focus on safety, cleanliness, and meeting agreed deadlines. Fully committed to customer satisfaction, I maintain clear communication throughout the project to ensure expectations are met and results are delivered to a high standard.
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Artisan Transformation LTD
No reviews yet
Extension Builder in Harrow, Greater London
Artisan transformation is a UK based design and build company. We pride ourselves in customer satisfaction. We have over 12 years experience in all aspect of work ranging from designing bespoke furniture to entire house renovations, to landscaping and imprinting or paving. We’re happy to work with designers and architects. We work to the highest specification, we can work to pre-agreed budgets whilst ensuring to deliver on time to meet timescales.
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HAMPSHIRES BUILDING & REFURBISHMENT
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We are a trusted family run company with 18years experience working in full refurbishment and partial re-modelling of properties. We undertake all aspects of high end building work including Extensions, Loft Conversion, Electrics, Plumbing, bespoke Kitchens, Bathroom, Built-in furniture all decoration and flooring. We have worked all over London restoring Georgian, Victorian and Edwardian properties. We have worked with English Heritage, Grovsvenor Estates and many London based Architects.
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Latest review:
Extensions- 11 Jun 2017
Neil and his team were the perfect builders. They did the job, quickly & efficiently. Always on time. Very honest builders. We were so lucky to have picked them. Also a great team to have around. Thankyou Neil.
MacG Ltd
No reviews yet
Extension Builder in Harrow, Greater London
We are a construction company, who works mainly with the refurbishment of the domestic sector. We do all of the works regarding construction sites, anything you need we will deliver you. Many years of experience on the tools let us be sure of what we doing and make happy our Clients.
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Simonmastermfp
No reviews yet
Extension Builder in Harrow, Greater London
Hi My name is Szymon and I have many tears of experience in the profession 14 years. I am responsible person who will do the work accurately and cleanly.I have references and photo of the wirj performed. I am waiting g for proposals for cooperation.
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VHP construction limited
No reviews yet
Extension Builder in Harrow, Greater London
Expert builders with over 2 years of experience serving north London. We specialize in high-quality Top Service, , extensions and renovations, carpentry, kitchen fiter. Plumbing , electric.delivering professional results on time and on budget. Reliable, clean, and fully insured—get in touch for a free, no-obligation quote today!"
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Lotus Trinity Limited
No reviews yet
Extension Builder in Harrow, Greater London
At Lotus Trinity we deliver state of art workmanship, exquisite customer service, quick turnarounds and competitive prices with efficiency and pride. Our friendly project managers will work one-to-one with you to ensure that each project is completed to your highest satisfaction. Founded by Sabin, who has over 20 years experience of working in the construction industry, along with our project managers with a similar level of expertise, we have knowledge and experience of the industry and nearly every niche within it. We strive to make the building process as stress free for our clients as possible throughout transparency and by keeping them up to date on everything that we do while delivering the highest quality work. Constant communication and quality control. Our clients projects are our business cards.
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DRYPSIAK
Rating: 4.9 out of 5
Extension Builder in Harrow, Greater London
Hello everybody! My name is Viktor. I am professional carpenter and joiner. I have big experience in first fix and second fix carpentry and joinery jobs. I install doors, skirtings, architraves, make partitions, and all jobs wiht wood. I make lofts conversion. I have experience 7 yers in carpentery and joinery, and lofts conversion. I also have big experience in bricklaing jobs, and in extention jobs.
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Latest review:
Carpentry- 21 Dec 2025
Viktor and Michael are very friendly and professional. They were on time and the price quoted was the price I paid. I hired them to install architraves around 4 internal doors and I am very happy with their work. They made sure I was happy with the work before they left and they took time to clean up after as well. They take real pride in their work as all the joints are perfectly aligned and all the nails are sunk in to the wood so I can apply filler afterwards and paint. Viktor also made a quick trip to Screwfix to ensure he used the strongest adhesive to fix the architraves to tiles in the bathroom. I will hire Viktor and Michael in the future to refurbish my stairs and install wall panelling on the stairs wall. I highly recommend them for their honest and professional work.
Pano Building Services LTD
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Welcome to Pano Building Services, a London based Home renovations & Building company. We cover all building aspects from Renovations, Bathrooms, Tiling, Roofing, Bricklaying, Extensions, Loft Conversions, Landscaping and many more. We also work very closely with surveyors, architects and structural engineers. We are always happy to help. Please feel free to get in touch for any questions/queries. We look forward to hearing from you.
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Latest review:
Restoration & Refurbishment- 22 Nov 2023
I had an out door room in my garden put up by some cow boys which I was left with needing a multitude of problems fixing. Our budget was quite tight but Pano provided us with quotes for each stage of the job detailing what was included in each stage this was really helpful. Pano was great at discussing and suggesting best ways to find solutions understanding our budget we never felt pressured to spend more. We trusted his guidance in the best way to complete the work. Pano always turned up when he said he would and at the end of each day left areas clean and tidy. Now the job has been completed we have the out door room we wanted and are really happy with . I would absolutely recommend him to anybody looking for a builder and would contact him again for further work . Thanks again 😊
Geni Renovation
No reviews yet
Extension Builder in Harrow, Greater London
Looking for a reliable team to deliver high quality renovation? Look no further! Here at Geni Renovation we overtake all jobs, and can count on dedicated teams with excellent skills which can renovate at high standards, on budget and time without ever compromising on quality.
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3.9

Top rated Extension Builders

Our Extension Builders in Harrow, Greater London, 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, Greater London?

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, Greater London 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, Greater London who are available and interested can respond to your post.

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

What are the hourly rates of extension builders in Harrow, Greater London?

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

Find extension builders in Harrow, Greater London with MyBuilder

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

Step 2: Compare different extension builders in Harrow, Greater London

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

Step 3: Hire Harrow, Greater London extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Harrow, Greater London, 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, Greater London extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Harrow, Greater London extension builder before hiring?

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

An extension builder in Harrow, Greater London 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, Greater London 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, Greater London?

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, Greater London 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, Greater London 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, Greater London

Can an extension builder in Harrow, Greater London help with planning permission?

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

Many Harrow, Greater London 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, Greater London help with materials and finishes?

Yes, most extension builders in Harrow, Greater London 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.