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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London & Kent Best Kitchen & Bathroom Solutions Ltd.
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Our highly skilled team of builders, carpenters, electricians, decorators and plumbers are reliable, trustworthy and dedicated to achieving the highest quality finish for your project; however large or small. Each project is tailored to your requirements and managed via a single point of contact.
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Latest review:
Bathroom Fitting- 26 Nov 2020
Sylwester and team did a fantastic job and were incredibly accommodating and polite with all of our requests. Would definitely recommend.
H&J Properties 02 Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
H&J Properties is your friendly, reliable small team with over 10 years of experience in the building industry. We design, plan, build, and project manage, so you can rely on us for a full round of service. From floor and wall tiling to full kitchen and bathroom installations, we’ve got your home covered. We handle plastering, painting, drylining, insulation, and more with precision and pride. Need a loft, rear or basement extension, a new roof, or concrete work? No problem. Whether it’s bricklaying, basement waterproofing, or installing windows and doors, we bring craftsmanship and care to every job. Big or small, we build it right. Please message us directly for more project images.
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Latest review:
We have contracted H&J Properties for our house refurbishment in London. I was impressed with the team's professionalism and project management from start to finish. We had no plans or planning approved, so we wanted a design and build company who will be able to look after the project from start to finish. They did just that. Working with the architects and the planning application before starting the project planning. As always, there are, of course, unforeseen issues arising with the old houses in london but I could't be happier with the communication received from the team. Thanks for the great job.
Signature 1 Construction Ltd
Rating: 4.5 out of 5
Extension Builder in Harrow, Greater London
Signature 1 Construction LTD is a family run business with over 25 years experience in the building industry. We specialise in extensions, loft conversions and full house refurbs. Every job we undertake we take great care of the clients house and are experienced project managers will look after you from start to finish.
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Latest review:
Extensions- 30 Sep 2025
Overall, I’m very pleased with the work Marin has carried out for us and I’m currently in the process of instructing him to do more work. Marin built a high spec cedar shed for us with electrics and plumbing, some brickwork and laid composite decking. Marin came across, honest and reliable, which in itself is rare. He was on site most mornings to make sure his tradesmen were on the right tracks. Like with a lot of these things there were some issues along the way and I was highly impressed by Marin’s ‘no quibble’ approach to rectify any problems. I myself have a high attention to detail and am quite indecisive (nightmare client) and Marin was happy to work with me with changes to the project without incurring extra costs.
GSS Develoments LTD
No reviews yet
Extension Builder in Harrow, Greater London
We are an established construction company operating since 2006. We do house extensions, Loft Conversions, and full refurbishment work.
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Organisedproperty.ltd
No reviews yet
Extension Builder in Harrow, Greater London
We have extensive experience in construction for over 15 years, many satisfied customers with our work, the last projects we did were the Osterley and Isleworth areas. We provide a free assessment of your work, our employees are certified according to British standards, we guarantee quality work for one year. Our company motto is, if you pay, we work.
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LEBELLE HERITAGE & RESTORATION LTD
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Lebelle Heritage & Restoration Lebelle Heritage & Restoration is a professional building and construction company specialising in renovations, refurbishments, and heritage restoration. We take on all types of projects, from full property renovations and structural upgrades to detailed interior finishes and the careful restoration of period features. Our team is skilled in both traditional craftsmanship and modern construction methods, allowing us to deliver work that is reliable, high-quality, and built to last. Whether we’re restoring the character of an older property or breathing new life into a modern home, we focus on precision, honesty, and clear communication throughout every stage of the job. We pride ourselves on delivering clean, efficient, and well-executed work that meets the needs of our clients and respects the integrity of each building. At Lebelle Heritage & Restoration, we build, renovate, refurbish, and restore with a commitment to quality and long-term durability.
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Latest review:
After a previous contractor took our money and left our loft extension unfinished, we were devastated and worried about how we would ever get our home back to normal. Then Lewis from Lebelle stepped in and completely turned things around. Lewis was patient, understanding, and incredibly professional. He worked quickly, kept costs under control, and finished the loft extension to a standard we’re so happy with. The stress he took off our shoulders was unbelievable. We honestly can’t thank Lewis enough. If you’re looking for someone trustworthy, skilled, and genuinely caring, Lebelle is the company to call.
MUZAAL construction limited
No reviews yet
Extension Builder in Harrow, Greater London
A professional and friendly construction team and our aim is to keep our clients happy and satisfied.
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RM Grand Builders Limited
No reviews yet
Extension Builder in Harrow, Greater London
We are general Experienced builders,who are willing to undertake any tasks! Costumer focused, Professional and friendly.
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Morina Property Limited
No reviews yet
Extension Builder in Harrow, Greater London
At Morina Property we deliver bespoke Building and Maintenance services to home owners and businesses. Providing Consultancy Service, creating project plans and dealing with planning consent, services issues and supporting project owners in dealing with day to day issues including delivery of project on time and within budget. Specialised in refurbishments and development of properties. Property and Block Maintenance. Complete Project Management from beginning to end.
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AVR Construction
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
I have a 10 years in construction industry ( landscaping) dancing paving foundations and many more For a fare quote contact me .
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Latest review:
Groundwork & Foundations- 17 Jun 2026
Contacted me the same day and did the job the same day. Cleared up nicely. Recommended.
JCH BUILDING SERVICE
No reviews yet
Extension Builder in Harrow, Greater London
I have over 25 years’ experience in the building trade, working across residential projects of all sizes. Over the years I’ve completed multiple garden extensions, loft extensions, full house renovations, and everything in between. I’ve seen it all and know how to handle jobs properly from start to finish. Based locally and happy to travel within the surrounding areas for the right job. I’m flexible, reliable, and always upfront about availability and travel before starting any work. my skills cover all core aspects of domestic building work, including: • Extensions & structural alterations • Loft conversions • Full property renovations • Brickwork & blockwork • Foundations & drainage • Steelwork (RSJs & structural openings) • Plastering & making good • Rip-outs & prep work • General handyman & repair jobs I coordinate work efficiently and ensure all jobs meet Building Regulations standards. I regularly work on prestigious homes and for long-standing clients who trust me as their first call for building work. I take real pride in what I do and I’m a perfectionist when it comes to quality and finish. I believe in honest work, clear communication, and leaving every job done right.
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Malhi Buildtech Service Ltd
No reviews yet
Extension Builder in Harrow, Greater London
We will provides a full building service. We are experienced builders who gives you highest quality work and very competitive quotes. We specialize in: • Extensions • Loft/Flat roof/Fibreglass • Asbestos removing • Brick work/Pointing • Plastering • Painting/Decorating • Wall papering • Tiling • Electrical jobs • Plumbing • Door/Windows .Kitchen/Bathroom • Carpentry/Staircase/Flooring • Gardens .
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DC Brickwork
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Dear Customers I am honest trustworthy reliable and hardworking and I have over 25 years experience in the industry.
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Latest review:
Bricklaying- 29 Jun 2017
I would recommend Damian. Did a good job, good communication and was on site when he said he would be. Polite and friendly. I would be happy to use again.
Brother builders limited
No reviews yet
Extension Builder in Harrow, Greater London
All buildings work undertaken
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CIF Builders
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We are family run business and have been in the trade since 2001. Our professional team will always give the best they can to achieve optimal results and most important for us are the finishing details and customer satisfaction. We can provide a range of different services from conversions, to extensions, bathroom and kitchen fittings and full restoration.
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Latest review:
Extensions- 28 Mar 2021
Amazing work from CIF Builders: John and his team delivered an amazingly looking extension and were a pleasure to work with. I have no doubt I will employ them again!
Am@ contractor
No reviews yet
Extension Builder in Harrow, Greater London
I will like to make my one customers
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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.