Extension builders in Harrow

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.5 (15 reviews)

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Some of our top rated extension builders in Harrow

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studioTO limited
No reviews yet
Extension Builder in Harrow
We are here to give you confidence to create a home, that is an intuitive reflection of your personality & your lifestyle. Space, that enhances your wellbeing and helps you perform better. If you want to improve your existing house or build a new one, we are here to guide you. WE HAVE YOUR BACK! We embrace our clients as individuals with unique beliefs, characteristics & aspirations. With our assistance you will have better clarity on what you need, want and what can be achieved.
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Build Better contractors ltd
No reviews yet
Extension Builder in Harrow
Build Better Homes & Construction is a trusted local building company delivering high-quality workmanship at competitive prices. We specialise in garage builds, house extensions, home renovations, painting and decorating, door installations, insulation, and all aspects of general building work. We pride ourselves on being reliable, professional, and committed to completing every project to a high standard. Customer satisfaction, honest communication, and attention to detail are at the heart of everything we do. Whether you're improving your home or planning a larger project, we're here to help bring your vision to life.
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Build Four Four Limited
No reviews yet
Extension Builder in Harrow
Build Four Four is a full service building construction company dedicated to building and improving residential and commercial structures according to client needs and desires. We specialise in transforming your home into what you always wanted. Be it a loft conversion, extension or a new build from scratch. You can be rest assured that at BFF, quality, precision and excellence comes first. Based in Hertfordshire but also covering London and Essex, the team at BFF is ready to give your space whatever updates it requires. Just give us a call or enquire online today and we’ll get back to you as soon as we can with a quote.
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Super Active Partners Limited
No reviews yet
Extension Builder in Harrow
A family owned construction company with over 40 years of experience. We provide our customers with the fastest and smoothest of services in order to get the job done quickly and efficiently. Good supplier relationships is a key factor to our success as it allows us to maintain our competitive edge.
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Tech-Team Construction
No reviews yet
Extension Builder in Harrow
Professional interior and construction photographer with vast experience. My clients are construction companies, interior designers, architects and craftsmen who want to have a good portfolio of their work and proper website.
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Multiple Constructions
No reviews yet
Extension Builder in Harrow
At Multiplex Construction, we are a dedicated team of professionals specializing in residential and commercial construction projects. With our expertise, we transform spaces, provide innovative solutions, and deliver high-quality results that exceed our clients' expectations.
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London Building & Design LTD
New on MyBuilder
Extension Builder in Harrow
From new builds to stunning home renovations, London Building & Design Ltd brings over 20 years of residential construction expertise to every project. We specialise in refurbishments, extensions, kitchens, bathrooms, and bespoke home improvements as well as garden fencing, delivering quality results you can trust.
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biggerstaff
No reviews yet
Extension Builder in Harrow
Hard working punctual
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Marco ltd
Rating: 4.6 out of 5
Extension Builder in Harrow
we put effort and commitment into our work so that the client is satisfied with our work
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Latest review:
Hard Flooring- 1 Sep 2026
I WANTED TO LEAVE A MINUS REVIEW BUT THERE IS NONE, THAT IS WHY I HAVE LEFT THE LEAST POSSIBLE SCORE. I PERSONALLY DO NOT THINK THIS GUY CALLED MARCO KNOWS ANYTHING ABOUT BUILDING AT ALL. HE IS A ROGUE BUILDER. HE SAID HE HAS 25 YEARS BUILDING EXPERIENCE, WHICH IS A LIE. I CALLED HIM TO DO MY FLOORING, KITCHEN CABINET, TOILET. PAINTING, FIXING LEAKS. HE RUINED THE WHOLE HOUSE. 8 MONTHS ON, WE ARE STILL REDOING ALL THE WORKS HE DID, HE JUST SPLASHED SILICONE ON THE UPVC TO FIX A LEAK. THE LEAK CAME THROUGH THE CEILING UNTO THE FLOOR CAUSING A BIG FLOOD IN THE HOUSE. HE IS THE MOST UNTIDY BUILDER. HE SAID HE WAS PAINTING, HE SPLASHED PAINT ALL OVER THE HOUSE, HE KEPT SAYING HE WILL TIDY IT UP AT THE END. UP TILL NOW, 8 MONTHS AFTER, I AM CLEARING THE MESS. ALL THE GROUT HE PUT ON THE TILES CAME OFF THE FIRST TIME I MOPPED THE KITCHEN FLOOR. ALL THE TILES HAVE MARKED PAIINT ON THEM AND IT IS EXTREMELY DIFFICULT TO REMOVE THEM BECAUSE THERE IS A LOT OF THEM.
Electrical
No reviews yet
Extension Builder in Harrow
Electrical work
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Kaseno Group LTD
Rating: 5 out of 5
Extension Builder in Harrow
Our company is based in London. We do all aspects of the construction. Our main target is to achieve the finest quality of our services and to satisfy any of the clients' requirements deliver the project on time and achieve a reasonable price.
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Latest review:
Kitchen Fitting- 19 Jan 2019
Very good, professional ,trustworthy team.I can recommend them to anybody. Their communication was excellent. The work they have done is of high stardard and was done on time.
R baciu
No reviews yet
Extension Builder in Harrow
Designer and artist who conceives, design and creates luxury dwellings and runway clothing. in addition to dwellings Ramadan has designed restaurants, lounges and Luxury Clothing. If you have any questions, get in touch Flooring Tiling Plumbing Electrical Kitchen fitting Wardrobes fitting TV mounting Locks changing Shower fiting Taps changing And more
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KD Building & Design LTD
No reviews yet
Extension Builder in Harrow
Hi my name is krasimir dimitrov, I have been in the trade for plus 10 years, my company does loft converions, extensions, new builds, patios drive ways, gardens, new bathrooms & kitchen fittings, and many more.
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Malkeet Mangat Roofing And Building Contractors Ltd.
No reviews yet
Extension Builder in Harrow
we are roofing and building specialist started in 2007, and it became a limited company in 2011. our company also do all type of building projects big or small. like loft conversion, house extension, house renovation and any type of building work. we also specialize in roofing work, pitch roof, slate roof, plain tile roof, all types of flat roof.
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SLL PrimeBuild Ltd
New on MyBuilder
Extension Builder in Harrow
Hi, I'm the director of SLL PrimeBuild Ltd, a reliable local building company based in North London / Haringey. I have over 10 years of hands-on experience in the trade — working as a self-employed builder and for established companies — delivering high-quality work across residential projects. We specialise in: ✅ Loft conversions & house extensions ✅ Full renovations & refurbishments ✅ Kitchens & bathrooms ✅ Roofing, brickwork & repointing ✅ General property maintenance & repairs Fully insured, reliable, and detail-focused. We provide free written quotes and keep clients updated at every step. Send me a message — I look forward to hearing from you!
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Prince Design London
No reviews yet
Extension Builder in Harrow
hello ,my business is high end and I work with very good architects or with clients who require a very professional builder who also has a design degree and highly skilled craftsmen who work for me . 15 years experience in construction before that 10 years as a furniture designer and cabinet maker I would take on quality building work of most types from lofts to extensions to new builds ,I think my website will show you the quality of works we undertake .
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4.5

Top rated Extension Builders

Our Extension Builders in Harrow, are rated 4.5 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.