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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E.E Builders & Decorators
Rating: 4.7 out of 5
Extension Builder in Harrow
With over 12 years of experience Think Beyond LTD has earned a high reputation with our professional, high standard finish, clean and tidy way of work. Loft conversions , house extensions, full house refurbishments, bathroom and kitchen fitting and much, much more ! We cover all London areas.
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Latest review:
Painting & Decorating- 1 Jul 2017
I would highly recommend these guys. They did a very high quality job decorating my lounge, dining room, hallway and stairs. They started the job on time, worked through the weekend to get the job finished in good time, left the place clean and tidy at the end of every day, and cleaned up immaculately at the end of the job. The price was also very competitive compared with other quotes I received. I hope they are available again in a few months time when I have more decorating that needs to be done.
Ervis
Rating: 5 out of 5
Extension Builder in Harrow
We take on all kind of work that you need to do. We have been doing this for almost 8 years. We even do foundations digging muck away etc. Please do contact us for any further information we more then happy to answer.
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Latest review:
Handyman- 22 Dec 2025
Was very quick to respond and complete this job 3 hours later. To a high standard.
BUILDING MASTERS LTD
No reviews yet
Extension Builder in Harrow
BUILDING MASTERS aim to deliver service safely, on time, within budget and in a manner that is considerate to the environment and to a quality standard that you expect. I have been in this business for Many years and knows how much it means to save up build your dream.That is why I take personal interest in every job to work with you every step until the job is done. Our services include: New Builds, Extensions, Loft Conversions, Garage Conversions, Complete Refurbishment.
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Platinum Build Services
No reviews yet
Extension Builder in Harrow
Normally we undertake :- Installing Extensions, Porches, new Kitchens, new Bathroom, Electrical, plumbing, tiling, skim & plastering, laminate flooring, Painting & Decorating
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Mandeep
No reviews yet
Extension Builder in Harrow
Hi I’m professional builder. Specialist in all type of building work
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alpha green construction
Rating: 5 out of 5
Extension Builder in Harrow
I have 25 years experience in the trade.specialise in innovation and reliability. Trade built company generally around masonry , roofing and all other structural undertakings. We specialise in loft conversions and house extensions , masonry and landscape gardening. We also provide design and build schemes for the above topics.
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Latest review:
Extensions- 14 May 2019
We love Berry, he has followed our project from the beginning to the end and he has been there all the steps of the way. He listened to our ideas and enriched them with more of his adding his special attention to details skills. For every problem, we had along the way he talked to us making sure we were happy with alternative solutions. Plus he is able to create a friendly working environment which makes the invasion of your house less intrusive, he has been very respectful of our space. We can genuinely say that he has gone beyond our expectations, and will be very happy to do future works with him. Luca and Nick
E&S building construction LTD
No reviews yet
Extension Builder in Harrow
We are a family run construction company dedicated to meeting all your construction work needs to high standard
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Donaghy & Ross Construction
Rating: 3.7 out of 5
Extension Builder in Harrow
At Donaghy&Ross we believe on delivering only the highest quality of work to ensure are clients get the best possible service, with 16 years of experience and NVQ qualifications in brickwork we have the right team to do the right job.
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Latest review:
Bricklaying- 12 Nov 2016
Dear Brian I have tried to contact you on several occasions to complete the job. I really do not wish to leave negative reviews all over the Internet. Will you get in touch? Just ignoring the situation will not go away as I am now in receipt of your insurance documents and want to resolve amicably. I put you on notice to get in touch within 7 days. If I do not hear back I'm afraid I will have to start the legal processes as you give me no other option. I hope to hear from you within the allotted timeframe and do hope we can avoid litigation in this circumstance. Thank you. Dawn
Sher group of builders Ltd
No reviews yet
Extension Builder in Harrow
Hi everyone, Please get in touch for reasonable quotation : ( SHER GROUP OF BUILDERS LTD) Company no : 12538248 Based in Hayes (west London) Loft conversion, extension, new build home, Complete home renovation,bathroom,kitchen Electrical,plumbing, All building work undertaken
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KXL GARDEN HOUSES LTD
No reviews yet
Extension Builder in Harrow
Welcome to KXL Garden houses Ltd At KXL, we specialize in turning your vision into reality. With years of experience in the construction industry, we are dedicated to delivering high-quality craftmanship, reliable service, and projects completed on time and within budget. Our services include: Home extensions, renovations and new builds. Outbuildings: Garden studios, Houses, Playroom or any others with choice of Sauna, toilet/bathroom, Bar or Others. Inside house works: Painting, tiling, flooring and others. What sets us apart? . Professional Expertise: We work with skilled tradespeople and ensure every project meets the highest industry standards. . Customer-Focused: Your satisfaction is at the heart of everything we do. From the initial consultation to project completion, wee will guide you every step of the way. . Transparency: We pride ourselves on clear communication, honest pricing, and delivering exactly what we promise. Whether you are building your dream home, upgrading your space, or embarking on a commercial project, we're here to bring your ideas to life. Let's build something great together. Contact us today to discuss your project.
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SLRA Ltd
No reviews yet
Extension Builder in Harrow
Builder company, refurbishment and new build. Bespoke joinery, wardrobes, kitchens etc.
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RG construction
No reviews yet
Extension Builder in Harrow
I build new house, Extension, Kitchen fittings, Fence, Flooring work, Paint and decoration, Garden work
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Tosum Sardeshi
No reviews yet
Extension Builder in Harrow
I a director of my own limited company that have been working in the building industry since 2004. I have studied carpentry and joinery and hold a city and guild certificates for three different levels. I am trained as a SMSTS for almost 15 years, temporary coordinator, PASMA, first aider, working at hight etc. I have worked on different project with big and small Fromm £ k to £1 million runing day to day project with all tasks risks, method of works and all work regulations. Reding all different drawings and applying this on site. I also worked on tools like a carpenter, rsj installer, ground work like underpinning, slabs, first and second fix all sort of carpentry and handy man. Partiion, door installation, roof work, roof dormers, lofts, kitchen installation,floor installation, skirting etc. I have an humongous knowledge and experience on most of building work on general, Any work is good for me big or small.
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Dobruna Construction Limited
Rating: 5 out of 5
Extension Builder in Harrow
Dobruna Construction Limited is happy to assist with any kind of building project, big or small. It’s our aim to make your vision reality and help you to improve your home for you and your family. Our work ethic is friendly, efficient and professional.
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Latest review:
Undertook extensive building work - a rear and side extension, built a summer house, landscaped the garden and paved a new driveway. They are the best building company I have ever worked with. Courteous, tidy, excellent quality, considerate of our family and our neighbours. Afrim consistently gone went and beyond to ensure that my renovations were completed to a high standard and at a fast pace. I am so pleased I made the decision to let him manage the building work from start to finish as his electrician, plumber, tilers, kitchen fitters have all been fantastic. Building works can be extremely stressful but Afrim did everything to make sure it has been as smooth as possible - would highly recommend
EmiMata
Rating: 5 out of 5
Extension Builder in Harrow
All building maintenace Painting All sort of Carpentry Building Gardening
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Latest review:
Groundwork & Foundations- 29 Nov 2025
Working with emi was a breeze
CALLAN GROUP LTD
No reviews yet
Extension Builder in Harrow
Our team are on hand from start to finish, working alongside professionals to ensure seamless communication, on-site organisation and solid, quality work every time. From architects, bricklayers, groundworkers, electricians, plumbers, to renderers, painters and decorators. Your project is guaranteed to be completed over and beyond your expectations.
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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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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.