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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Sam's Building Maintenance and Constructions Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Sam's Building Maintenance and Construction Ltd has more than 25 years experience in First and Second Fix carpentry, Kitchen installation, extension, loft conversion and general refurbishment work. We deliver quality services to meet customers' specifications and within stipulated deadlines .
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Latest review:
Sam did 5 and half meter kitchen, with large shower and laundry rooms extension for me. He is of very good character, worked professionally, reliable and his work was good.
ak london builders
No reviews yet
Extension Builder in Harrow, Greater London
AK London Builders is a reliable and professional team specialising in extensions, full home renovations, bathrooms, tiling, plastering, painting & decorating, and carpentry work. We have a skilled team for every stage of the project and always focus on clean, high-quality workmanship with attention to detail. Customer satisfaction is our priority, and we proudly offer up to 5 years guarantee on selected work for complete peace of mi .
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Stones Woodburners
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
At Stones Woodburners, we offer much more than just expert heating solutions. In addition to our certified stove and heating system installations, maintenance, and repairs, we specialize in custom building services, including the creation of unique fireplace surrounds, mantels, and beams. We work closely with our clients to design and build features that complement their homes, adding both function and style. Our team of skilled professionals is experienced in every aspect of heating system care and home building, ensuring that your wood-burning stove is not only efficient and safe but beautifully integrated into your living space. Whether you’re looking to install a new stove, replace a worn-out mantel, or create a custom fireplace feature, we provide top-tier craftsmanship and attention to detail. We are fully insured, Hetas registered, compliant with all necessary regulations, and committed to delivering sustainable, efficient, and aesthetically pleasing heating and building solutions. Hope to speak to you soon!
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Latest review:
Fireplaces & Flues- 18 Dec 2025
Brilliant - would re-hire in a heartbeat! Excellent service and clear communication
H & A Rail ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We are a Civil Engineering Contractor
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Latest review:
Groundwork & Foundations- 22 Dec 2021
I couldn't have asked for more from this firm.... called when they said they would, arrived early and did everything they could to take away the stress of this stavr in my build. Clean and tidy works, pleasant and polite workforce. I will always use this firm for my work and highly recommend them
Home Renovations Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We're a building company specializing in house extensions, loft conversions and refurbishments. Our clients come from New Malden, where we're based, but also surrounding areas. The vast industry experience enables us to provide valuable advice, professional services and individual approach, benefiting our customers. As we understand trust and credibility are crucial when undertaking such projects, we arrange viewings and provide customers with references and photos of our most recent projects.
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Latest review:
Extensions- 24 Jun 2017
We had a large piece of work done by Johan and his team. It was a 4m single storey rear extension with new kitchen installation, converting the old kitchen into a downstairs bathroom and utility room, plus other bits and bobs like new boiler, rear patio. We got quotes from a few builders, Home Renovations weren't the cheapest, they were actually towards the higher end. But we went and saw their previous work and spoke to some of their other clients. The work was done to a high quality and the clients seemed to be happy so we decided to go with them. Johan's team are very hard working, professional and polite. Pawel and his team of builders, bricklayers, plumbers, electricians, etc. would turn up before 8am and finish at 6pm working solidly throughout the day. There is Magda as the project manager who keeps you in the loop, and answers any of your questions (which we had many). There is Michaela on the finance side who keeps you up to date with the budget. Our budget went over by 5% with "variations" (extra work or materials) but it was always communicated why and the work wasn't done without our approval. Pawel would give his recommendations but the final word would always be ours. But these things can add up. Overall we were very happy with the build, it was done to a very high standard. They also finished it before time. They said it would take 12 weeks in fact they finished it in 10 weeks which was amazing as you would normally expect these things to go over.
ABG Builders Ltd
No reviews yet
Extension Builder in Harrow, Greater London
ABG Builders we do all sorts of building projects and have been running since 2006 we specialize in extensions from foundation to finish we make sure our costumer achieves their dream home. Free quotations
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Sokhalconstructionltd
No reviews yet
Extension Builder in Harrow, Greater London
My name Parwinder Singh & my company name Sokhalconstructionltd i carry out wide range of building work including extension renovations general i am provements new build .loft conversion.i have (how many years of experience) i am fully insured and experience in coordinatings projects from start to finish. My aim is to keep the process clear organised and hassle free my approach is simple realistic time scale transparent pricing I am happy to discuss your plans and provide a free no obligation quotation
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DAAS DEVELOPERS LIMITED
Rating: 2 out of 5
Extension Builder in Harrow, Greater London
We are Specialists in Extensions & Refurbishments, Bathroom designing and installations, Floorings , Painting & Decorating and General Building with 20 years of experience in Building Industry
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Latest review:
Extensions- 8 Jan 2023
Avoid. A total nightmare. Avoid.
The london Loft and Kitchen Company
Rating: 4.5 out of 5
Extension Builder in Harrow, Greater London
We are a southwest London Based loft and kitchen extension specialist. Our working area is very small with 90% of our jobs in Wandsworth and any work outside this area is never more than a mile or two away. With over 15 years experience in this area we know inside and out how these properties were built so when it comes to structural alterations you couldn't be in safer hands.
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Latest review:
Extensions- 16 May 2017
Initially apprehensive about using mybuilder, we found David easy going, clear and concise from the offset. The work carried out was to a high standard and any changes or questions that arose he was all to happy to answer. We found him to be pro-active in his approach, open and honest with how much items cost and sensible when agreeing monthly valuations. Both of us work in the construction industry and it is enjoyable and a breath of fresh air when you get to work with people as straight forward a David. We hope to do work with him again and would be happy to talk with anyone who is considering taking him on for additional work. Many thanks, Rob and Brom
Amrit pal singh
No reviews yet
Extension Builder in Harrow, Greater London
I am very Hard work and kind loyal and go to work daily and only take breaks on Sundays and start jobs at 8:00 o'clock and end at 5:00 o'clock at Late afternoon.
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MO Construction
No reviews yet
Extension Builder in Harrow, Greater London
SUITE 504, CUMBERLAND HOUSE, 80 SCRUBS LANE, LONDON, NW10 6RE AMO Construction Group Ltd is a lean, high-performance construction company delivering end-to-end building solutions with zero compromise on quality, safety, or timelines. With over 15 years of industry experience, we operate with a founder-led mindset, tight operational control, and a culture built around precision execution. We specialise in residential and commercial construction, structural works, refurbishments, and full-scale project delivery. Our approach goes beyond building — we orchestrate projects from concept to completion. Every job benefits from senior-level oversight, fast decision-making, clear communication, and a delivery pace that consistently outperforms traditional contractors. Clients work with us because we reduce friction, protect budgets, and deliver measurable value. We combine a small, agile team with big-project capability, maintaining relentless standards of workmanship and accountability on every site. Small team. Big output. That’s the AMO Construction standard
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Saj
No reviews yet
Extension Builder in Harrow, Greater London
Hi ,, Got a 25 years experience in trade .we are a full-service building contractors dedicated to turning your architectral vision into reality . Specializing in new builds , extensions and complex renovations ,our team manages every phase of your project from intial planning and site preparation to subcontractors co-ordinations and final inspectors . Here to help u .in any kind of building projects .thank u so much .
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Pro-Ferb Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We have been trading since 2006 most of our work has been in the west end of London but due to the demand for our high standards of workmanship and professionalism in 2014 we started undertaking jobs in Surrey and surrounding areas. We have an architectural designer if you require planing, building control drawings as well as full design and working drawings. References and a portfolio available on request.
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Latest review:
Brilliant team, Robert and his crew outstanding. Robert in total control , organised and always in communication with me. Cannot thank him and his team enough. Scary prospect going some major building works on my own but felt totally confident in him from start to finish. Would definitely recommend him . Final word: Robert THANK YOU MY FRIEND, Ann
Bardhi Construction
No reviews yet
Extension Builder in Harrow, Greater London
Hi, We are a small building company that undertake majority of building works. With 17 years of experience of working in mainly in domestic buildings we offer a wide range of services. We are not the cheapest however we believe in fairness and most important providing fine quality work. If interested please do not hesitate to contact me direct. King regards Tony
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Jsb project ltd
No reviews yet
Extension Builder in Harrow, Greater London
Hello, This is JSB Project ltd. We are based in West London. We do Loft extensions, Garages, All kind of Extensions, Renovations, Kitchen bedorrms ans so more. We have projects around London. Free qoute. Please contact us for any inquiries. Thanks. Kind regards
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Cinnamon Design Studios Limited
Rating: 4 out of 5
Extension Builder in Harrow, Greater London
Avenue Developments is a development consultancy, taking projects from inception to completion, in time and within budget. We offer our clients a tailored service, by evaluating each project to identify where value can be added and where potential problems may arise. We are committed to the quality of our professional service and have proven to satisfy our client's expectations.
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Latest review:
CAD / Drawings- 6 Dec 2019
Lack of professionalism! Called me at 2150 to say was interested in job, warning signal but said far enough so booked an appointment. He didn’t turn up nor respond to my texts asking if he was held up somewhere. I am not sure how trustworthy he is.

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.