Extension builders in Harrow

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.3 (16 reviews)

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Some of our top rated extension builders in Harrow

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FF Building Contractors Ltd
No reviews yet
Extension Builder in Harrow
FF Building Contractors Ltd are a family run business who specialise in all types of general building, construction and structural works. We have earned the reputation of providing thorough, quality workmanship from planning to completion and take pride in delivering the highest standard of work for our customers. Our aim is to deliver a personable and friendly service and ensure our customers are kept informed throughout the entire project.
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Kingsmarque construction and maintenance
Rating: 5 out of 5
Extension Builder in Harrow
All building work taken on, slating and tiling, house renovations and extensions. We have a team of tilers, renderers, plumbers, painters and myself and business partner who run each job and manage the multiple trades required.
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Latest review:
Extensions- 25 Aug 2020
Really professional and quick to provide quotes. Unfortunately, due to COVID and our circumstances changing, we have had to cancel the job. We would definitely go back to them in the future though.
Mani builder
No reviews yet
Extension Builder in Harrow
How can I help you I have 4 experience in this field and I love to help you to get your things done . I’ll bring my own tools and am very good in my work.
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KK Home Solutions
No reviews yet
Extension Builder in Harrow
At KK Home Solutions, we provide reliable home improvement and property services tailored to our customers’ needs. We cover a range of services including cleaning, flooring, gardening, handyman work, driveways and general home improvements. We work with experienced and reliable tradespeople to ensure each project is completed to a high standard, with clear communication from start to finish. Our aim is to make the process simple, professional and hassle-free for every customer.
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JAS Builder
No reviews yet
Extension Builder in Harrow
I’m an experienced and reliable builder with over 7 years in the trade, specialising in loft conversions (including double bedrooms with en-suites), new builds, rear and side extensions, and full home renovations. I take pride in delivering high-quality work, sticking to deadlines, and making the process smooth and stress-free for my clients. Whether you’re expanding your home or starting fresh, I’m here to help bring your vision to life.
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Toro Construction Ltd
No reviews yet
Extension Builder in Harrow
I like to set up all details before rather than arguing after
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Iulian
No reviews yet
Extension Builder in Harrow
My name is Julian I have ben working in this industry for 17 years. during the great period of time we installed Cw door windows, stick sistem but also cladding, decking, balustrades, cladding, decking, SFS, plasterboard
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Bricklayer
Rating: 5 out of 5
Extension Builder in Harrow
We carry out all types of building work to a very high standard. We pride ourselves on our friendly team and can do attitude. We will treat your home Like ours and make every effort to you updated before, during and after the works. We are extremely hard working and always give 100% on each job we undertake.
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Latest review:
Driveways (Paved & Loose)- 17 Apr 2021
Dorel was a very pleasant person .He arrived on time and did a brilliant job . He finished earlier than expected and reduced the agreed quote which I haven't had from anyone else I've hired . I highly recommend Dorel .
Floodgate and Harvey field group ltd
No reviews yet
Extension Builder in Harrow
We understand total house/property refurbishment such as kitchen, bathrooms, showers, toilet, flooring, painting and decorating, tiling, brickwork and many more. We give quality work and satisfaction for your money. We are timely. We are top at our job. We don't mess around.
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NK BUILDING SERVICES
No reviews yet
Extension Builder in Harrow
I am a builder by trade , I undertake all aspects of general building services. I have 25 years experience in this industry, my work includes, extensions, renovations, refurbishment, kitchens, bathrooms, landscaping, loft conversions, carpentry, and no job too small.
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C C M BUILDERS
No reviews yet
Extension Builder in Harrow
CCM Builders began as a general works contractor in 2011. Over the years, the company has undertaken many challenging projects and accumulated a range of skills and experiences on design and building solutions, project management services, building trades and related engineering works. I am a reliable professional, with emphasis on clear communication and follow through procedures, ensuring that client’s objectives are top priority and delivered in a timely manner.
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Rucky
No reviews yet
Extension Builder in Harrow
Welcome to Rucky Construction, where we turn your dreams into reality! With decades of experience and a commitment to excellence, we specialize in delivering top-notch construction services tailored to your needs. Whether it's residential, commercial, or industrial projects, we bring expertise, quality craftsmanship, and a customer-centric approach to every job. Let's build something amazing together
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N. G. IONITA
No reviews yet
Extension Builder in Harrow
With over 13 years in the trade undertaking all sorts of works from ground works to roof works we have been shifting throughout all the works that involves building a house, yet we might not have achieved the best knowledge in plumbing and electricity be rest assured that we can still provide advice, accommodate and protect other peoples work in your project.
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Buddy
Rating: 5 out of 5
Extension Builder in Harrow
Welcome! My name is Buddy. I work with a team of amazing colleagues, and we complete jobs ranging from decorating to driveways.
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Latest review:
Painting & Decorating- 9 Sep 2021
Very hard working and fast would definitely recommend. Job is good quality and no hassle.
j ward joint sealing specialists ltd
Rating: 5 out of 5
Extension Builder in Harrow
Est 2010, we have grown our business and expanded . We have worked for some of the largest developers in the country on properties up to £70 million. 2015 was the turning point for us going to a Ltd company ahead of target. We expanded our business to bespoke design and build and specialize in refurbishment properties and major extensions with a large client base across the east, south, and west counties, including work in the Cotswolds. We have now expanded in PROFESSIONAL SNAGGING. We also specialize in feature wall paneling. All of our tradesmen are certified in their fields. References and photographic evidence can be provided. We take the strain from any job and provide all trades, Project management and Produce quality work to the highest of standards.
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Latest review:
Extensions- 8 Oct 2025
Jason and his team have just completed our wraparound extension, and the result has exceeded all expectations. Their workmanship, accuracy, and attention to detail are outstanding, and the whole process was smooth and stress-free. They stuck to timings, kept the budget in mind, and made everything feel effortless. Partway through the build, Jason had to undergo an operation and was signed off for five weeks. Remarkably, nothing was delayed — his team carried the project seamlessly, and with Jason still on site when he was able to be, everything ran perfectly. It’s a real credit to how capable they all are and the consistently high standards they work to. The only negative thing I can say is that we were sad to see them leave – they’ve been such a positive part of our daily lives over the past eight weeks. The finish is exceptional and we’re absolutely over the moon. We couldn’t recommend Jason and his team highly enough.
Kang work ltd
No reviews yet
Extension Builder in Harrow
Kang work is a reliable building and property development company providing high-quality construction services across London and the surrounding areas. We specialise in house extensions, loft conversions, full property refurbishments, new builds, kitchens, bathrooms, roofing, brickwork, landscaping, and general building work. We take pride in delivering quality workmanship, honest pricing, and completing every project to a high standard. Customer satisfaction, clear communication, and attention to detail are at the heart of everything we do. Whether it’s a small repair or a large construction project, we’re committed to providing a professional, reliable, and stress-free service from start to finish.
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4.3

Top rated Extension Builders

Our Extension Builders in Harrow, are rated 4.3 out of 5 based on 16 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.