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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Resst Construction
New on MyBuilder
Extension Builder in Harrow
Resst Construction Ltd has been delivering high-quality construction and refurbishment services since March 2011. With over 100 successfully completed projects, we have built a strong reputation for excellence, reliability, and attention to detail throughout South West and West London. We specialise in high-end refurbishments, transforming properties with exceptional craftsmanship and a professional approach tailored to each client’s vision. From residential renovations to complete property restorations, our experienced team is committed to delivering outstanding results on every project. Resst also focuses on Kitchen extensions, Loft conversions as well As Full house refurbs At Resst Construction, we pride ourselves on exceeding customer expectations through quality workmanship, clear communication, and dedication to client satisfaction.
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Maclondonbuilding
Rating: 4.9 out of 5
Extension Builder in Harrow
MACLONDONBUILDING specialist in general construction and renovation services. All kind of house conversions . Our works are performed at the highest standard with attention to the details. Professional team always happy and enjoyed of the work.
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Latest review:
Tiling- 16 Jan 2026
Mac was fantastic and went above and beyond to do the job to a high standard, working well into the evening to get it done. I’d recommend him without hesitation for any work you need doing - big or small. We’re delighted with the finished product.
Perpetual Growth Limited
No reviews yet
Extension Builder in Harrow
Hi there, I have over 20 years experience in building extensions, landscaping and bathroom refurbishments.
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SST Homes LTD
Rating: 3 out of 5
Extension Builder in Harrow
Here at SST Homes, we have been providing building services for over 15 years. We take great pride in carrying out all types of building works including New builds, Renovations, Extensions, Loft conversion, Commercial projects, Maintenance contracts and Smart Homes.
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Latest review:
Extensions- 13 Nov 2020
Avoid these traders. They are amateurs and have caused me no end of pain with a small single storey front extension. I sacked them in the end as we just could tale anymore of their slap dash approach.
Brick & Block work
No reviews yet
Extension Builder in Harrow
We are specialist in Brick & Block works and all building work undertaken With the experience of more than 20+years
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T De Maio Brickwork services
Rating: 5 out of 5
Extension Builder in Harrow
Our aim is simple, Obtain repeat business and recommendations by providing customer focused services, producing high quality work on time and within budget. Please take a look at my photo gallery of the work myself and the team can produce, our work speaks for itself👍 Kind regards Tony De Maio
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Latest review:
Bricklaying- 28 Jul 2019
With me having no previous experience and knowledge. Toni was helpful and I felt that what ever I asked Toni to do, he could provide. I trusted him completely with what I asked, and he was the best quote by far. Toni helped with where to purchase what was needed and was clear and transparent throughout. I am even thinking of having more work done now I know what can be produce.
NICER LTD
New on MyBuilder
Extension Builder in Harrow
We are a reliable and professional Chinese building team based in London, specialising in residential renovation and property improvement work. Although we are new to MyBuilder and do not yet have reviews on the platform, we have completed a wide range of projects for homeowners and landlords across London. We are happy to arrange viewings of previous completed work for peace of mind. We understand that good communication, reliability, and keeping to budget are just as important as the quality of the work itself. We take pride in being: • Punctual and hardworking • Clean and respectful in customers’ homes • Transparent with pricing and quotations • Efficient without cutting corners • Focused on delivering a professional finish We cover all aspects of home improvement, including bathrooms, kitchens, flooring, decorating, carpentry, and general building work. Our aim is simple — to provide dependable workmanship at a fair price and make the process as smooth and stress-free as possible for every customer.
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Groundwork and Landscaping Services Ltd
Rating: 5 out of 5
Extension Builder in Harrow
Local professional builders with a vast experience installing fencing, paving and general groundwork, we offer competitive prices and good quality finish. We specialise in all aspects of gardening, landscaping and groundwork, we strive to make each garden unique and listen to our clients' individual wishes and requirements. We strive to create a space you can really enjoy.
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Latest review:
Landscaping- 25 Mar 2022
Fatmir was very professional and delivered a high standard of work at a fair price. Reliable, on time and listened to what I wanted. He communicated throughout the job. I am delighted with my fencing and patio he provided. Very trust worthy professional who values is customer and work. Highly recommend and have passed his contact to my neighbour and friend. Thanks Fatmir
jrs renovations
No reviews yet
Extension Builder in Harrow
Let us help building your dream Our Mission At Ringoy Construction, our mission is to redefine the construction experience by delivering exceptional craftsmanship and innovative solutions. from minor renovations to major new builds, not only meets but exceeds the expectations of those we serve. With decades of experience across London, we pride ourselves on building not just homes, but lasting relationships with our clients. New Builds Renovations Extensions Design Consultancy
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Primo Contractor Ltd
No reviews yet
Extension Builder in Harrow
At Primo Contractor Ltd, we take pride in delivering exceptional construction and renovation services throughout London. Specializing in loft conversions, home extensions, remodeling, and full property refurbishments, we transform homes with precision and craftsmanship, tailored to the unique needs of each client. Our team of skilled professionals is committed to completing every project to the highest standard, ensuring attention to detail and quality finishes in every aspect of the build. With years of experience in the industry, Primo Contractor Ltd has earned a reputation for reliability, innovation, and customer satisfaction. Whether you’re looking to expand your living space, modernize your interiors, or completely refurbish your property, we provide comprehensive solutions that blend functionality and style. From initial consultation to project completion, we manage every stage of the process, offering personalized service and expert advice. At Primo Contractor Ltd, we believe that every home has the potential to be extraordinary. Let us bring your vision to life with our expertise and dedication to excellence.
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Restful Abodes Ltd
No reviews yet
Extension Builder in Harrow
Construction company based in London
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FKF CONSTRUCTION COMPANY LTD
New on MyBuilder
Extension Builder in Harrow
I take pride in the quality of my work and stand behind everything I deliver. All work carried out is completed to a high standard using reliable materials and proven methods. I offer a guarantee on my workmanship, giving you confidence that any issues arising from my work will be addressed promptly and professionally. My goal is to ensure every project is completed to your satisfaction and built to last.
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Pro House&Office Fit Out
New on MyBuilder
Extension Builder in Harrow
We are a highly reliable and experienced construction company known for delivering top-quality workmanship. Our team focuses on precision, durability, and customer satisfaction in every project. We take pride in meeting deadlines and exceeding expectations.
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KK Pro Construction Ltd Uk
No reviews yet
Extension Builder in Harrow
KK Pro Construction are a North London based company carrying out construction services, property maintenance and installation work across London We specialise in loft conversions, extensions and basement excavations.
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Mario Services
Rating: 5 out of 5
Extension Builder in Harrow
Mario & Alex Construction LTD specialise in construction and building services, complete property refurbishment, house extensions and loft conversions. Provides unmatched customer service. Our commitment to small,hudge integrity, providing the highest value and satisfied customers, has been the ingredient that has fueled our growth from the beginning. We ensure that all our work is professionally managed so that the result is of outstanding quality, cost-effective.
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Latest review:
Bathroom Fitting- 20 Jan 2023
We highly recommend Mario & his team. They fitted a new kitchen & bathroom to a really high standard within a short, timeframe. They work hard, are friendly, professional & honest, my neighbour even commented on how considerate they were! Upon first meeting Mario we were impressed by how organised he was. He arrived on time with the description we’d posted on my builder & went through it methodically. We had A LOT of questions! He answered all of them & didn’t rush us. We received a competitive quote within a day as promised. It included everything we discussed & he quickly answered our follow up questions. We wanted an accurate idea of the cost of electrical work & Mario arranged for his electrician to come & inspect/quote before we’d appointed Mario the job. Our kitchen & bathroom is complicated, with lots of difficult angles. Damp, unlevel floor, unlevel windows, a low ceiling were uncovered in the bathroom. Mario did well to identify solutions, giving us expert advice. Pipes were neatly chased into the wall. Underfloor heating & LVT, tiling, grouting & painting all done to a very professional finish. He kept us informed of progress, checked our preferences & was patient when we had supply delays, finding ways to ensure the job finished on time enabling us to move from our temporary accommodation back home in time for Christmas. He promptly fixed some minor issues after the job finished. We highly recommend Mario & would use him again.
Quality Build Ltd
No reviews yet
Extension Builder in Harrow
I am a professional builder with 20 years experience, I specialise in loft conversions and extensions. I have a full team providing customers with a high quality finish every time. I have plenty of references and photos of previous projects if required.
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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.