Extension Builders in Harrow, Greater London

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.9 (16 reviews)

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Some of our top rated extension builders in Harrow, Greater London

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Lasting Ltd
No reviews yet
Extension Builder in Harrow, Greater London
At LASTING LTD, we specialise in high-quality residential construction and full property renovations across London and the surrounding areas. With years of experience and a strong reputation for reliability, we deliver projects with exceptional craftsmanship, clear communication, and attention to every detail. Our services include complete home refurbishments, loft conversions, kitchen and bathroom installations, structural works, flooring, plumbing, heating and electrical upgrades, and all types of internal finishing. Whether it’s a single room or a full house renovation, we provide honest advice, transparent pricing, and results built to last. We take pride in working cleanly, safely, and efficiently, ensuring every project is completed to the highest standards. Most of our clients come back to us again and again — because they trust our workmanship and appreciate our professional approach. If you’re looking for a reliable contractor who delivers quality without compromise, LASTING LTD is here to help bring your project to life.
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GSK
No reviews yet
Extension Builder in Harrow, Greater London
Hard working methodical tradesperson with a proven track record of large and small projects.
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Param group
No reviews yet
Extension Builder in Harrow, Greater London
Hi, Here we are satisfy you by our work and quality thanks
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wd7homeimprovements
No reviews yet
Extension Builder in Harrow, Greater London
I've 20+ Years experience in Plumbing and Multi trade works overseeing multi year contracts for Brent Council and other area's. I was lead over a group of multitraders, overseeing various sizable projects in the construction industry. I work as a plumber as my first trade and also cover multi trade and building works.
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Tosum Sardeshi
No reviews yet
Extension Builder in Harrow, Greater London
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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Prela LtD
No reviews yet
Extension Builder in Harrow, Greater London
I have strong experience in gardening, landscaping, and house repairs. I am confident in all aspects of the work I do, including maintenance, renovation, and practical hands-on tasks. I am dedicated, hardworking, and always focused on delivering high-quality results. I take pride in my work, learn quickly, and adapt easily to different types of jobs. I am reliable, motivated, and committed to completing every task safely, professionally, and on time
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Go&Ko Services Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Go&Ko Services LTD is a 24 hours Property maintenance company for the Public and Commercial with trust and confident in quality and high standard services. Our offers the following services on a residential and commercial basis: - General Building/Extension - Loft conversion - Refurbishment - Kitchen/bathroom installation - Carpentry - Tiling/Flooring - Plumbing - Drainage - Metal restoring/welding - Electrical - Decorating - Handyman - Fencing/Decking -
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Latest review:
VERY PROFESSIONAL WORK AND GOOD COMMUNICATION
Hys Contractors
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We are a very experienced company with over 25 years in the building industry. We undertake all building works from refurbishment, extensions, painting and decorating, tiling, plastering, electrics and plumbing. We operate all around London.
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Latest review:
Restoration & Refurbishment- 14 Mar 2022
Albert and his colleague were both very friendly, they completed the work within the time scale they said they would and to a high standard. I am very pleased with their work and will be using them again!
Rosa Construction
No reviews yet
Extension Builder in Harrow, Greater London
From internal renovations that breathe new life into your space to building extensions that expand possibilities, and loft conversions that elevate residential and commercial structures—we have the experience and skill to handle it all.
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Kastriot Avdiu
No reviews yet
Extension Builder in Harrow, Greater London
General building, lofts, extension, full refurbishment
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E.E Builders & Decorators
Rating: 4.7 out of 5
Extension Builder in Harrow, Greater London
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.
Jhony construction limited
No reviews yet
Extension Builder in Harrow, Greater London
We have 15 years of building work experience. We are a professional construction company providing complete building solutions across residential, commercial, and industrial sectors. Our services include new builds, extensions, renovations, and property maintenance. With a skilled team, quality materials, and a focus on timely project completion, we ensure reliable and affordable construction services you can trust.
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LondoNest Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Londonest is a London-based building company specialising in high-quality residential construction and renovation. We provide reliable and professional services including house extensions, loft conversions, full property refurbishments, kitchen and bathroom renovations, and general building works. Our team combines strong technical expertise with attention to detail to deliver projects that meet the highest standards of quality and safety. We work closely with our clients from the initial consultation through to completion to ensure every project is delivered on time, within budget, and to the client’s satisfaction. At Londonest, we pride ourselves on clear communication, transparency, and a commitment to excellent workmanship.
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Latest review:
We hired this builder for a 2-metre rear extension and a very large garage extension and we’re really happy with the result. The project needed a pile foundation which is a bit more complicated, but they handled everything very professionally. They listened to what we wanted and kept us informed at every stage, which really helped as we were living in the house while the work was being done. The team were friendly, easy to deal with and worked to a good standard. Overall a very good experience and we would happily recommend them.
Dynamic Build
No reviews yet
Extension Builder in Harrow, Greater London
Hi, I run a building company which takes on a diverse range of projects -from minor alterations to full refurbishments. Originally an electrician I have spent many years developing properties to maximise their potential. We offer a reliable and flexible range of services covering Hertfordshire and surrounding areas.
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D&P BUILDERS LTD
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We are general builders with 11 years experience. We are happy to undertake projects of all sizes.
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Latest review:
We required two extensions - to the rear and above the garage at the side. We contacted Darek as he was recommended to us by a work colleague who lives in our area. We found Darek's prices to be competitive and he was very reasonable to work with, being flexible when our plans changed slightly. Having building work undertaken is never a pleasure, in our view However, we're pleased with the completed work and we found that working with Darek was as stress-free as it could have been. We would (and have) recommended him to friends.
KXL GARDEN HOUSES LTD
No reviews yet
Extension Builder in Harrow, Greater London
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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3.9

Top rated Extension Builders

Our Extension Builders in Harrow, Greater London, are rated 3.9 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, 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.