Extension builders in Harrow

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.5 (16 reviews)

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Some of our top rated extension builders in Harrow

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Rolex Carpentry & Roofing
No reviews yet
Extension Builder in Harrow
Welcome to Rolex Carpentry & Roofing a company dedicated to providing the best possible service to its clients. We are a family owned and operated business and have provided quality construction services to our clients since 2002 We are skilled in all aspects of construction. We take pride in our workmanship and promise to provide you with the highest-quality finish on any project. We strive to make sure our customers are satisfied and that we exceed their expectations in every aspect possible
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Newcon London Ltd
New on MyBuilder
Extension Builder in Harrow
Newcon London Ltd and the Team have been doing Loft conversions, Extensions and building works in London for the last 24 years. We cover M25 and strive to do the works at highest standard and in time and budget.
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Starlight Distribution Ltd
No reviews yet
Extension Builder in Harrow
All construction work undertaken, specialising in kitchen extensions, loft conversions and outbuilding/annexes. We aren’t the cheapest quote. The quality of our work, completed in a timely manner makes us outstanding with 80% of our clients repeat customers! We will NEVER: Take your money and run ❌ Leave a job incomplete ❌ Ask for more money than agreed ❌ Be a nuisance and inconvenience ❌ We even bring our own kettle so you don’t have to make us tea!
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Plastering and K rendering
Rating: 5 out of 5
Extension Builder in Harrow
🏗️ General Builder • Roofing • Extensions • Refurbishment – London Looking for a reliable and professional builder in London? We provide high–quality construction and renovation services at competitive prices. ✅ Plastering & Insolation Silicone Rendering ✅ Our Services Include: • General Building & Refurbishment – Full house renovations, kitchen & bathroom fitting, plastering, flooring, painting & decorating. • Extensions – Single & double-storey extensions, side returns, rear extensions, loft conversions, and garage conversions. • Roofing Services – New roof installations, flat & pitched roofs, roof repairs, waterproofing, guttering & fascias. • Structural Work – Brickwork, concrete, foundations, and load-bearing alterations. 💪 Why Choose Us? • Experienced team with over 16 years in the trade • All work guaranteed & fully insured • Competitive, transparent pricing • Clean & reliable service – we treat your home with respect • Free, no-obligation quotes 📍 We cover all London postcodes – Central London,North, South, East & West.
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Latest review:
Plastering- 16 Mar 2020
Almed and his team came over to see the two bungalows and gave me a quote and was more reasonable than other quotes I had previously. Almed started the job and stated exactly what he was going to do from the beginning to the end of the job. He is a very professional and knowledgeable person and he and his team did a outstanding plastering job on my two bungalows and I’m very happy with the job and will highly recommend him for future projects. Thanks Zai
Anjelina
Rating: 5 out of 5
Extension Builder in Harrow
Hello, my name is Krasimir Dimitrov i am a tradesman, i deal with loft conversions, demolitions, new builds, extensions. I have been in the trade for over 10 years.
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Latest review:
Demolition- 17 May 2025
The team was great They did everything as they promised The job was finished on time Thanks for the help, it was much appreciated.
Adds Construction ltd
No reviews yet
Extension Builder in Harrow
I work in building general construction E.g. landscaping, plastering, plumbing, carpeting, fixer My company name: ADDS CONSTRUCTION
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Malkeet1construcstion
Rating: 5 out of 5
Extension Builder in Harrow
“Hi, I’m Gurpreet singh. I’m a qualified builder with 7 years of experience in residential and commercial work. I specialise in all type of building work such as renovations, extensions, and general building. I take pride in quality workmanship and reliable service.”
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Latest review:
Bathroom Fitting- 6 Sep 2026
Very happy with the work carried out by Gurpreet. Honest, reliable, professional and reasonable prices. I have no hesitation in recommending his work. New bathroom and kitchen fittings, painting and decoration.
ARD@AGD.Ltd
No reviews yet
Extension Builder in Harrow
Hi my name is Costel and my company name is ARD@AGD.Ltd ; We are working ; full refurbishment interiors, bathroom, kitchen fitting, tiling, flooring, painting and decorating, electrical, etc.
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CM Building LTD
Rating: 5 out of 5
Extension Builder in Harrow
At CM Loft Conversions, we specialise in luxury loft conversions, home extensions, and full refurbishments for both residential and commercial properties across London. Our dedicated team is renowned for transforming spaces with unparalleled craftsmanship and meticulous attention to detail. Whether it’s a high-end home, a modern office, or a commercial property, we deliver projects that elevate both form and function. By seamlessly blending design innovation with practical solutions, we ensure every project not only enhances the aesthetic appeal of a space but also maximises its value and usability. At CM Loft Conversions, we are passionate about creating bespoke spaces that reflect the unique needs of our clients. From concept to completion, we focus on the fine details and provide a smooth, stress-free experience. Whether you’re looking to transform your home, expand your business premises, or refurbish a commercial unit, our team is committed to delivering results that exceed expectations.
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Latest review:
I met Charlie and his team from CM Builders Ltd when they were completing a loft extension and ground floor extension for one of my neighbours. Quotation and budget I was given an estimate subject to drawings as I was on a strict budget that I had to keep to for the build. Charlie was able to help me keep to the budget, both at the final agreed plan and during the build. The project was complex in that whilst it was a loft extension, all of the house was rebuilt. The only thing kept was the external walls and first floor rafters. Whilst the footprint of the first floor was not being changed I wanted to bring it up to current building standards with extra insulation. All of the plumbing and electrics were also replaced including a new boiler. The overall build has come in on budget, save for agreed enhancements that I did not think of at the planning stage and or building regulations such as double ceiling fire plaster boards. There were also items such as the original stairs that I wanted to keep, but Charlie was able to increase the height space in the kitchen making the worktop much more usable for tall people for a larger part of the kitchen. These were suggested to me as potential options as part of the build. Stage payments The stage payments have all been sensible throughout the build and linked to the ongoing work schedule. I have not therefore had any concerns in this regard. Quality of work This was a very complicated build as unlike the ground floor the first and new second floor are “L” shaped. The new 2nd floor included an en-suite and 2 bedrooms. Overall the house has been increased from 2 bedrooms 1 bathroom, to four doubles and 2 bathrooms. The quality of work is excellent and Charlie project manages his team to ensure that they all deliver to a high standard- if it is not done correctlt they do it again, with Charlie spotting any issues. Timeline of build This has generally gone to plan very well. As with any build you have to be realistic as things will happen outside of anyone’s control. When issues have arisen Charlie manages them to a conclusion. Also be realistic if you are having to manage to a tight budget. I had to plan for various stage receipts of cash before I could order the kitchen and bathroom items - make sure you understand how this impacts the build and availability of the work force, recognising that CM Builders have to book kitchen fitters and plumbers. CM Builders are also very helpful in that they have sorted out issues with the brick work of my freestanding garage (nothing to do with the build) and also a neighbour’s wall that could have been dangerous to the public, should it have failed. Conclusion The whole family are very pleased with the outcome and we now have the equivalent of a brand new house that has been built to a very high standard. This has definitely been worth doing both from a valuation perspective and quality of life perspective. I would not hesitate to instruct Charlie and his team again.
SSS Brothers Limited
Rating: 5 out of 5
Extension Builder in Harrow
At SSS Brothers we value our customers and work very hard to maintain their trust.With 15 years of experience,You can be assured that we will always provide quality workmanship, professional,courteous and timely service. Our prices are competitive, and our work is guaranteed. We will not be satisfied until you are! What We love most about renovating homes is working with our clients to create something spectacular.Every job comes with new challenges and opportunities to build something special.
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Latest review:
Extensions- 26 Aug 2021
SSS BROTHER, They worked incredibly hard to transform our house in a timely and efficient manner, all whilst being responsive to our concerns and preferences. The SSS BROTHER did a great job extending our kitchen and backroom to create a beautiful space that we love hosting family and friends in. The job was completed to a high standard and with good communication. Throughout the work, the workers were calm and knowledgeable and - importantly for us - helpful and offered their opinion of how the extension should be built.
My Home Services London Ltd
Rating: 5 out of 5
Extension Builder in Harrow
My Home Services London Ltd is a professional construction and home improvement company specialising in bathroom and kitchen renovations, house extensions, loft conversions, and full property refurbishments. We also provide expert gas, electrical, electronics, and smart home (domotics) installation and maintenance services. Our team delivers complete, high-quality solutions designed to transform homes by combining functionality, comfort, style, and modern technology. From small upgrades to large-scale renovation and extension projects, we work with a safe, reliable, and professional approach tailored to each client’s needs and vision.
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Latest review:
Handyman- 29 May 2026
Absolutely fantastic service, they did a great job!!! Friendly and professional. I look forward to having them back for more jobs. 100% highly recommend!! Thank you very much!
Rathour
No reviews yet
Extension Builder in Harrow
All building work
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"Surudo" Building & Decorating
Rating: 5 out of 5
Extension Builder in Harrow
We are team of experienced builders provides professional execution of small, medium and larger projects, all types of refurbishment, maintenance and building services for private and business customers in London and surrounding areas. All of our work is carried to the highest standards.
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Latest review:
Bathroom Fitting- 3 Sep 2020
He is very professional and has done a good job on refurbishing my bathroom.
Jaches construction
Rating: 5 out of 5
Extension Builder in Harrow
Architectural Engineering drawings. Construction. Ground and first floor Extensions. Loft conversions. Interior design. Painting and decoration. Boiler installations.
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Latest review:
Conversions - General- 28 Jul 2023
I had Tony in to do my ballastrade, he also ended up doing a lot more work including my driveway, have recommend him to several people and all have used him, highly recommend
Space A construction ltd
No reviews yet
Extension Builder in Harrow
I did a lot of job in construction industry in Uk and all my customers happy years after the job have done.
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Himanshu
Rating: 5 out of 5
Extension Builder in Harrow
Whether you're looking to modernize your home's exterior, improve insulation performance, or create a stunning brick-effect finish, we provide tailored solutions that combine aesthetics, durability, and long-term value. Contact us today to discuss your project and arrange a free consultation.
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Latest review:
Insulation- 16 Sep 2026
I hired Himanshu to do my external insulation work and I was more than pleased with the work he did. He paid attention to details, he was patient with the job. Himanshu and his team were always on time and fast as well. They did an exceptional job on my property. I am definitely hiring him again for any building and insulation works. I highly recommend working with him.

4.5

Top rated Extension Builders

Our Extension Builders in Harrow, are rated 4.5 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.