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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j &k builders ltd
No reviews yet
Extension Builder in Harrow, Greater London
yes we doing loft conversion on very good price and great work we provide in short time
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R & K Contracting Ltd
No reviews yet
Extension Builder in Harrow, Greater London
R & K Contracting Ltd Amazing building contractors that cover absolutely everything. Where if it’s Exetentions, Refurbishment, New Builds, Plastering & Painting, Bathroom & Kitchen fitting and Many more. We have a lot of experience in the Building Industry with over 12 years experience.
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Jass
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We do all kind of staircase with fill finishing, Roofs Structure, Roof Tiles , installing doors , Flooring and other construction work.
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Latest review:
Carpentry- 1 Jul 2026
Jass was quick to respond and gave a good price for fabricating a staircase on site. Jass made sure I was happy before leaving and readjusted one of the steps which was creaking.
London builders limited
No reviews yet
Extension Builder in Harrow, Greater London
London Builders ltd ??????? 1. General builder/ property refurbishment:: 2. House refurbishmentsRenovations/ Extensions / Garage conversions 3. Loft / Attic/ Basement conversions , shop remodelling 4. New builds 5. Loft conversions 6. Complete refurbishments • All building services ⤵️ ✅Plastering / Skimming ✅Carpentry ✅Brick work ✅Decorating / Painting ✅Roofing ✅Gardening / Landscaping ✅Wooden floors ✅Kitchens / Bathrooms Refurbishments ✅Wall and floor tiling ✅Fencing / Paving / Driveways / Porches ✅Renovations / Extensions / Garage Conversions ✅Loft / Attic / Basement Conversions ✅Heating / Plumbing / Electrics ✅ New Builds ✅. Basements ✅. Loft Conversions ✅ Extensions ✅ Complete Refurbishments ✅ Garage conversions ✅. All Building services ✅ Painting and Decorating ✅ All Plumbing services ✅ All Electrician Services
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D&E Smart Building Solutions Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Loft conversion. New or refurbished extension. All Carpentry work. New decking or refurbished. Brick walls front of the house, or new building. New or refurbished bathroom, Tilse, Garden, Kitchen, Wood floor, Plumbing with certificate, Electrical with certificate, and much, much more..
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Latest review:
Bathroom Fitting- 7 Mar 2022
Daniel was great and we were impressed by the level of care and detail in his work. Would use him again and recommend to friends.
Basra construction London LTD
No reviews yet
Extension Builder in Harrow, Greater London
Hi my name Manjinder we are based in West London and we do loft conversion extensions refurbished new built and all building work.
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Smw general services ltd
No reviews yet
Extension Builder in Harrow, Greater London
Experienced handyman specialising in DIY projects, with a passion for tackling home improvement tasks of all sizes. Skilled in plumbing, building and general maintenance, I bring creativity, precision, and attention to detail to every project. From minor repairs to complete renovations, I thrive on turning visions into reality. Let's collaborate to transform your space into something extraordinary!
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Kallides&sons ltd
No reviews yet
Extension Builder in Harrow, Greater London
Kallides-Sons is a trusted design and build company based in South Ruislip, proudly serving clients across the surrounding areas. We offer a wide range of bespoke services designed to transform both the interior and exterior of your home with precision, creativity, and care. Every project we undertake is tailored to reflect your unique vision, combining functionality, beauty, and lasting quality Our expertise covers full refurbishments, kitchen and bathroom makeovers, home extensions, and detailed interior craftsmanship. Inside the home, we specialise in custom furniture, bespoke cabinetry, and fine woodwork, creating elegant and practical spaces that blend seamlessly with your lifestyle. Each piece of furniture and joinery is handcrafted to order, using premium materials and traditional techniques to ensure timeless appeal and exceptional durability. From concept to completion, our team works closely with you, offering expert guidance and creative insight to achieve results that exceed expectations. Beyond interiors, Kallides-Sons is equally passionate about enhancing outdoor living. We design and build patios, decks, and bespoke garden structures that extend your home’s living space and create beautiful, functional environment
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Alex Mihai
New on MyBuilder
Extension Builder in Harrow, Greater London
Hello! I have been working in this industry for over 10 years, having experience on building sites and on privat jobs aswell. I also do loft extensions , house extensions , roof refurbishment, groundwork and finishing touches to garden patios!
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C&M Construction (London) Ltd
New on MyBuilder
Extension Builder in Harrow, Greater London
Qualified and insured bathroom fitter and plumber specializing in complete renovations. Committed to tidy, reliable work executed strictly to UK building regulations. Focused on delivering a high-quality finish on time and within budget. We also do all kind of building works.
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Rajput construction
No reviews yet
Extension Builder in Harrow, Greater London
We are experienced and reliable builders specialising in house extensions, structural alterations and refurbishments. We carry out all work to a high standard and in line with Building Regulations. We pride ourselves on being punctual, tidy and professional, with clear communication from start to finish. Fully insured and committed to delivering quality workmanship on every project.
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DHARAM BUILDERS LTD
No reviews yet
Extension Builder in Harrow, Greater London
Welcome to Dharam Building Services, your trusted partner in construction and home improvement for over 15 years. With a passion for quality craftsmanship and a commitment to exceptional customer service, we specialize in turning your home improvement dreams into reality. Whether you're planning a renovation, need repairs, or want to enhance the functionality and beauty of your living space, we’ve got you covered. Our expert services include tailored consultations, drywall repair, exterior and indoor painting, flooring installation, and custom garage designs. We also offer general repairs and maintenance to keep your home in top shape, home extensions for added space, water fixture repairs, and tile work installation for lasting aesthetics. For those looking to maximize space, we specialize in loft conversions and extensions, providing you with more room to grow. At Dharam Building Services, we combine over a decade of experience with attention to detail to ensure every project is completed to the highest standards. Our satisfied customers speak for us, and we invite you to read their reviews on Google. Contact us today to discuss your next project—we look forward to helping you transform your home!
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Gagandeep singh
No reviews yet
Extension Builder in Harrow, Greater London
M Gagandeep work as the main work of plumber
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ALFA QUALITY CONSTRUCTION LTD
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
WELCOME TO ALFA QUALITY CONSTRUCTION LTD Expert Builders You Can Trust We are a team of experienced construction professionals offering top-notch services tailored to your needs. From small refurbishments to large projects, we deliver quality and reliability. Our expertise includes extensions, property maintenance, plumbing, electrical services, sustainable construction, wall tie replacements, and general building. We specialize in warehouse racking, mastic sealant, garage conversions, equestrian stables, concrete garages, agricultural buildings, cladding, core drilling, demolition, and foundations. Whether it’s garden studios, loft conversions, or fire and flood renovations, we bring unmatched craftsmanship. From concept to completion, we ensure durability and client satisfaction. Let us bring your vision to life with professionalism and sustainable practices.
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Latest review:
I thank Alfa Company for the work they did for me. Excellent service, on time and accurate work from the management and employees. I recommend them.
Satnam singh
No reviews yet
Extension Builder in Harrow, Greater London
I am a builder i was in this feald from 2006 and my best trades are loft conversion, extation kitchen bathroom ,electric and heating any kind of building work i can undertake .
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Properties Concierge
No reviews yet
Extension Builder in Harrow, Greater London
At Properties Concierge, we turn your vision into reality, whether it’s a dream home renovation or a commercial space transformation. Based in London but available to work anywhere, we bring over 5+ years of experience to every project. We handle everything from electrical and plumbing works, extensions, loft conversions, side extensions, boiler installations, to bathroom renovations, kitchen fitting and supply, and windows fitting and supply – all at unbeatable prices. We also offer free project management (depending on the project) to ensure your build runs smoothly. Our expert team is committed to honest, reliable, and high-quality craftsmanship, delivering exceptional service and seamless project management from start to finish. Let’s build something amazing together get in touch with us.
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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.