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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Ceca Developments LTD
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
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.
Baatth construction ltd
Rating: 4.9 out of 5
Extension Builder in Harrow, Greater London
All buildings work undertaken,extension ,loft conversion, plumbing, electrical, driveways
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Latest review:
Bathroom Fitting- 27 Dec 2021
Overall very Happy with the Job done.
Kuci max construction ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Kuci Max Construction Ltd. brings over 15 years of experience in the building industry, specialising in residential and commercial construction and renovation. Our services include, extensions, driveways, brickwork, garden & design, tiling, refurbishments, kitchen and bathroom installations, and landscaping. We are committed to delivering high-quality, customer-focused solutions with transparent pricing and full accountability. Our experienced team is dedicated to transforming spaces and bringing your vision to life. For review you can check on my website: KUCIMAXCONSTRUCTIONLTD on google!!
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Latest review:
Stonemasonry- 22 Dec 2024
Neatly finished job. Very cooperative team!
Perfect Install LTD
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Perfect Install is an refurbishment and extensions specialist with 6 years experience in the building industry, doing all kind of projects, from small bathrooms refurbishments up to full house refurbishment including wall demolishing and building, flooring fitting, tiling, full kitchen design and fit and high quality painting. We do have in house authorised electricians and gas certified plumber. We have a history of projects started as small parts of a big project which end up with us doing the entire project at customer request. We are working in an 30 miles radius from Watford and we did projects in the medium to high luxury part of the building industry, including residential, commercial and public institutions. We offer to our customers an hassle free experience, getting involved in planning, sourcing the materials and advising regarding the local regulations. All our work is backed by an insured warranty which give our customers the peace of mind that the project is done at the highest level of quality.
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Latest review:
Handyman- 28 Mar 2025
Amazing job, at a very fair price. The people who did the installation came prepared and were friendly, he even brought a laser to make sure the tilea were leveled.
W8 Build Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Hi, I’m Jon, the Founder of W8 Build. With over three decades of experience in both modern and listed buildings, I’ve dedicated my career to transforming spaces – from bespoke home extensions and loft conversions to the careful restoration of historic landmarks. I even had the honour of working on Windsor Castle alongside Her Majesty The Queen after the 1992 fire, a project that taught me how to balance grandeur with precision. At W8 Build, we believe exceptional craftsmanship should be accessible. Grounded in values of integrity, reliability, and meticulous attention to detail, my team and I bring the high standards of historic restoration to every project – all at market-competitive rates. Whether you’re seeking a stylish roof terrace, a complex basement conversion, or a heritage-sensitive renovation, you’ll receive a fixed-price, transparent proposal and a commitment to excellence that makes quality affordable. There are no hidden fees or inflated costs here – just clear communication, thoughtful planning, and the peace of mind that comes from working with a team that treats every project, whether a royal landmark or your family home, with equal care and professionalism. Let’s work together to bring your vision to life, blending timeless quality with modern practicality. Your dream space deserves nothing less. W8 Build by Jon Taylor
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Latest review:
Extensions- 14 May 2025
Jon was able to take a failed project from a previous contractor and manage historic building preservation, regulation in Westminster, a lack of parking, plumbing from the Victorian age, and a demanding client to deliver a beautiful result. I love my garden flat extension, it manages to respect the historic nature of a building from the 1840s while also adding amenities to be proud of in 2025. Thank you Jon (and team) and best of luck with future business.
Redmark Contractors Limited
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Redmark Contractors Limited have over 10 years experience, and with many years experience in the building trade. We are a professional team are reliable builders operating in London and the wider area. We take great pride in all work which we undertake, taking great care to make sure that our client’s needs are met in a meticulous and professional manner.
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Latest review:
Extensions- 27 May 2025
They helped build me two houses and were always putting their best foot forwards. Bhupinder and his team are lovely, and are now like family to me. They have a bright future ahead for themselves and for the clients they look after.
3 plastering guys
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
London home developers take care and pride in our professionalism. We ensure minimal fuss for our customers and provide them with an end project of their exact want. London home developers are able to complete clients jobs such as Loft and extension, brick work, steel work, partitions, plastering, plumbing, luxury bathroom and much mor.
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Latest review:
Plastering- 5 Jun 2026
Very skilled, professional and a great person. Thank you Rami
Plumb4All
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
With over 20 years’ experience in the plumbing and building industry, this has enabled our team at **Plumb4All** to become a well-known and trusted company. We offer a 24/7 call out service and long term support for existing clients as a single point of contact for any future queries and issues. Our many happy and repeat customers find us through word of mouth and being fully qualified gives you the peace of mind that quality of service and very high standards are at the core of our values.
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Latest review:
Bathroom Fitting- 7 Mar 2021
Very professional and very thorough Solved the problem efficiently Would definitely recommend.
New build, refurbishment & maintenance
No reviews yet
Extension Builder in Harrow, Greater London
Hello, We are a reliable construction company specialising in commercial & high end residential fit - outs & refurbishments. Our team is made out of skilled tradesman, reliable, experienced & knowledgeable. You'll have one reliable point of contact throughout the works and all the support needed. We take great pride in our work ethic and the quality of our finishes. New to "my builder", as opened an account to fill gaps between our normal projects but can give many references on request.
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Hillcroft Brickwork
No reviews yet
Extension Builder in Harrow, Greater London
Only recently joined MyBuilder. 30 years experience in construction. We are specialists in brickwork, groundworks and hard landscaping. We can provide a free no obligation quote. Jobs of any size taken on.
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AVStructures
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
A.V. Structures is a construction company working with top-rated contractors and providing services to private clients around London. Our highly experienced team of builders has excellent skills and knowledge gained delivering projects locally and abroad. We approach each building process following Environmental, Health, and Safety guidelines. All our quotes are free, and we will always try to get a quote to you within a week of us visiting your property.
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Latest review:
Demolition- 24 Nov 2021
We employed A.V Structures for the building of an external wall around our property, the removal of a garage and the installation of railings and gates. Throughout the 4 week programme we could not have been happier with their work. Arrival was prompt, their pace of work displayed energy and purpose. They were mindful of us and our neighbours and made sure the area was left clean and tidy at the end of each days work.in addition the workmen were courteous and kept us fully informed. Alex, the owner of the company, kept in close contact with us to assure himself of our satisfaction. He came on site at intervals to check that all was going according to plan. We therefore felt completely confident that quality and outcomes were important to him. Employing A.V Structures was a decision we were pleased to have made. We would use them again without hesitation and recommend them highly to anyone considering similar work.
Hritz uk
No reviews yet
Extension Builder in Harrow, Greater London
Plumber, bathroom fitter, carpenter, dry linner, plasterer,electrian...almost all skills necessary for refurbishment, maintenance and upgrades domestic dwellings
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Pascal renovation limited
Rating: 1 out of 5
Extension Builder in Harrow, Greater London
My business is focused around construction and renovation of domestic properties no job is too small or too big, we undertake all sorts of construction from simple repairs to full house renovation, extensions, gardening and landscaping driveways and paving. I've been in the industry for the past 7 years as self employed and last year I've decided to go a step further and start this company
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Latest review:
Extensions- 13 May 2021
Gave a quote, never got back to me on email, didn't hear from him again.
Arjan
No reviews yet
Extension Builder in Harrow, Greater London
Refurbishment works, extentions, lofts, includes a team I have( carpenters, electrician, plumber, plasterers, painters, dryliner.
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AVOTERG Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Our aim is to help clients achieve their objective on time and budget and to the highest standard. We value the good communication with the clients, and try to have as much information as possible with regards to how their project must look when completed.
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Latest review:
The job was a complete refurbishment of a one bed flat, including rewiring and re-plumbing. We would recommend Al and his team without any hesitation. From the very beginning and all the way to completion, we felt very lucky and fortunate to hire them. We found them to be very hardworking, conscientious and professional. The job was a difficult and complex one, but the team still completed within time and within budget. Al's advice made the whole process easier and we found him to be very trustworthy and honest. The end result was better than we originally hoped for and was done to a high standard.
96 Degrees Carpentry Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We undertake all aspects of Carpentry and General building works. Specialising in refurbishments and loft conversions we have a team of qualified and experienced carpenters, plumbers and electricians available for both residential and commercial works.
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Latest review:
Decking- 23 May 2021
Excellent and professional job completed as quoted. Would highly recommend to future Clients.

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.