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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THE OREILLY GROUP LTD
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We undertake all Groundworks packages to simple repairs to large site packages.Having been in the industry almost 20 I have worked on a number of large scale projects including RAF Northolt,Harry Potter world London and many housing developments. All our lads are fully trained and certified,including Cscs,Cpcs,first aid etc.We own all our own plant from 1 tonne to 30 tonne excavators, dumpers, skips and grab lorrys.Here at The OReilly Group we pride ourselves on repeat business & recommendations
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Latest review:
Groundwork & Foundations- 25 Jul 2023
The Oreilly Group completed my groundworks, external drainage and some knock throughs on my extension. The job commenced when promised and was completed within programme. The works were completed on time and this included some extras I threw in along the way. I would reccomend Owens team for any groundwork and drainage project - very happy with the outcome.
Ethan ansell
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Hello im Ethan, a fullyqualified bricklayer with 15 years experience of erecting brickwork. I am very proud of every job i have carried out and i build with pride. I ensure nothing less then the highest quality of work and a fully satisfied customer. I look foward to building for you whoever you are.
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Latest review:
Bricklaying- 8 May 2021
Ethan did an excellent job for us today. Very impressive brickwork. Nice friendly guy and left the place clean and tidy after finishing. Will not hesitate to use him again for future work.
K.M Home Construction
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Our company deals with construction and renovation. We are professional. We ensure a high standard of our work, we keep the agreed deadlines.
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Latest review:
Bathroom Fitting- 11 Oct 2023
He was very professional and has completed the work as desired.
Otters Group Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Welcome to Otters Group Ltd page, With over 20 years of experience in the construction industry, we deliver high-quality construction solutions for both residential and commercial projects. From start to finish, we manage every aspect of construction with professionalism, precision, and care. Our team of skilled, reliable, and dedicated professionals is committed to exceeding expectations by delivering projects on time, within budget, and to the highest standards of quality. Customer satisfaction is at the heart of everything we do. We work closely with our clients throughout the construction process, upon completion, and during the defect liability period to ensure long-lasting results and peace of mind. **Your time, cost, and quality are our priority on every project.**
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Latest review:
Painting & Decorating- 19 Jun 2024
I recently had the pleasure of working with Mahdi and his team, and they were excellent. They were knowledgeable, did the work efficiently, and cleaned up thoroughly afterward. I was extremely satisfied with the quality of their work. I would highly recommend them and look forward to working with them again in the future.
AAB Home Builds Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We are limited co. General builders. WE TAKE CARE TO NEW BUILD, EXTENSION AND LOFT CONVERSION Specialists in exterior RENDER (WEBER ,KEY RENDERING&SILICONE RENDERING)and interior plastering. Bathrooms kitchens and refurbishment works.
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Latest review:
Plastering- 23 Dec 2016
Denis did a good job plastering and retiling a small area of my kitchen. He responded to my ad promtly, came round the next day to quote and carried out the work 2 days later as requested. He was professional, polite and left my kitchen clean and tidy after the work was done. I'm happy to recommend him and would contact him again if needs be.
RA Designs and Build Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We are a dynamic construction firm specialising in innovative design and high-quality building solutions for both residential and commercial projects. With a commitment to excellence and attention to detail, our team of experienced architects, engineers, and skilled tradespeople collaborates closely with clients to bring their visions to life. We prioritise sustainable practices and utilise cutting-edge technology to enhance efficiency and ensure the durability of our structures. From initial design concepts to final construction, we are dedicated to delivering projects that not only meet but exceed client expectations, creating lasting value and aesthetic appeal. Our customers consistently recommend us for our commitment to quality, attention to detail, and exceptional customer service. They appreciate our ability to turn their visions into reality while staying on schedule and within budget. Positive testimonials highlight our professionalism, seamless communication, and the collaborative approach we take throughout each project. Clients feel confident entrusting us with their building needs, knowing that we prioritise their satisfaction and work tirelessly to ensure memorable and successful outcomes.
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Latest review:
Excellent quality of work which has not caused any problems for many years. Efficient work style whilst keeping up a high standard of work.
CN1 Ltd
No reviews yet
Extension Builder in Harrow, Greater London
Since being formed in 2018 CN1 Ltd has grown into an established leading construction contractor offering a multi-disciplined package to all major main contractors across the United Kingdom. Having been part of many prestigious developments, including such projects as Shoutwark in Egham, East London - a development of houses, flats, sheltered housing and offices moving on to major roles in some of the UK's leading developments such as the Westcome and more recently on the Central London . CN1 Ltd continues to grow, proud of its achievements and enthusiastic about its future continuing to operate in all sectors of the construction industry.
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Earthmates Construction Limited
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Introducing Earthmates: Your trusted partner for all property needs. We offer comprehensive services in new builds, extensions, landscaping, fencing, loft conversions, and complete property management. Whether you’re planning to build from the ground up, expand your existing space, or enhance your outdoor area, Earthmates delivers expert craftsmanship and tailored solutions to transform your property vision into reality. Let us help you create, renovate, and manage with quality and care at every step.
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Latest review:
Landscaping- 20 Sep 2025
Earthmates absolutely transformed my garden. They did an amazing job so I hired them again to redo my driveway. I would definitely recommend them an would hire them again an again. They were a good bunch of guys friendly and professional. If you want a job done right hire Earthmates Construction!
Km Building Specialists Ltd
Rating: 3 out of 5
Extension Builder in Harrow, Greater London
KM Building Specialists is dynamically developing company created by people with passion. Our mission is professional advice, meeting expectations and, as a result, obtaining satisfaction of all our clients. We work closely with various construction specialists (electricians, gas-safety experts, architects, garden designers) to enable us to deliver the top class service and to ensure that the safety building regulations and codes of practice are followed.
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Latest review:
A single storey extension. Bedroom chimney place knocked down. Patio to the rear. Marek was very hardworking, professional and tidy. He was at my home every day and alway very early and always worked until late to get the job done
Indrit
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
kitchen fitting-painting end decorations- renovations ol the house
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Latest review:
Decking- 7 Jun 2022
1000 stars!!! I have never, ever, seen a team work as professionally, quickly and expertly as what these guys did. They laid a whole 6x3 decking in 2 days. They worked non stop and went well above and beyond expected. Will never use anyone else for any work ever again. So glad I found Indrit!
Craft of London Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Craft of London are an established building company, specialising in design and build projects, creating bespoke interiors and homes. Our workmanship is of the best standard in London for either small, medium or grand designs.
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Latest review:
Extensions- 3 Sep 2013
Kel and his team worked on my single storey extension with bifold doors and glass roof. He also did some landscaping in my garden, replacing the fencing and installing a raised patio with cedar battens to the side. Overall I was very pleased with the work Kel did. He is a good communicator and frequently visited the site to keep on top of the work. Kel was happy to discuss requests and was flexible with design changes. The bulk of the work was completed on time with just some minor snags remaining, but the finish is excellent. It's been a long and stressful journey, but it's been easier with the friendly support and professional approach Kel has taken to his job. I'd be happy to recommend Craft of London and provide a reference on request.
Brando Developments Ltd
Rating: 3.7 out of 5
Extension Builder in Harrow, Greater London
Brando Developments, with a solid decade of trading since its establishment in 2012, has become a trusted name in the industry. Specializing in a range of services, we proudly collaborate with local estate agents, addressing diverse needs such as maintenance issues, end-of-tenancy work, and expert painting and decorating services. Our dedicated team includes skilled professionals, including gas engineers, electricians, and roofers, ensuring that we offer comprehensive solutions for our clients. With a proven track record, we continue to provide top-notch services, making property management and development a seamless experience for our valued customers.
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Latest review:
Bathroom Fitting- 10 Oct 2024
Really good team. The work was excellent. The only thing to comment is that the team could have finished the work faster but overall I’m happy with their work. Very involved and caring team. It felt like they were doing their own bathroom. Good price as well.
Tim
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Im specialise as grand working
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Latest review:
Fencing- 25 Aug 2022
Time was very professional and the job was very well done.
Rutba design & build ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
I provide complete building services like loft conversion, side & rear extensions, kitchen, bathroom, plumbing, underfloor heating, electric & driveways, painting & decorating etc.
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Latest review:
Absolutely great quality of work and outstanding service. Jagjeet and his team have done a great job without any delays. Honest and hard working. Very happy to recommend Rutba
AH Builder
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
AH North Builder Ltd specialise in all types of building we are professional and very determined to ensure our clients expectations are met. we have worked on many different building projects for more than 10 years experience.
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Latest review:
Extensions- 13 Nov 2020
Well, I do not usually write reviews, but this time is an exception. So after getting a number of quotations, I decided to go ahead with Fredi. The process was very smooth throughout, Fredi is a great individual and a reliable professional. The plan was to build a rear extension, but working with Fredi, we decided to commission him for the patio, changing all house flooring, kitchen, and two bathrooms. All have been delivered to completion with top-notch results. Most importantly, we have now a new family friend...Fredi the builder!!.. my kids say :)
First Choice KB Constructions Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
At First Choice KB Construction Ltd, we pride ourselves on being your go-to solution for home improvements projects. With a wide array of expertise in house extensions, refurbishments, loft conversions, and the renovation of bathroom and kitchens, we’re fully equipped to tackle diverse projects. Our services span across various aspects including brickwork, plumbing, electrical, and more, ensuring a comprehensive approach to every job. Our team boast over a decade of experience in the field, ensuring that we deliver results that stands the test if time. At First Choice, our goal is clear: to provide top-notch quality work that lasts, while adhering to agreed-upon timelines. We prioritize flexibility to accommodate our customers’ unique needs and preference. No project is too small for us. We're dedicated to delivering excellent service, ensuring that our clients' needs and requirements are not just met, but exceeded. Customer satisfaction is our ultimate priority.
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Latest review:
Extensions- 30 Jun 2024
Absolutely brilliant from start to finish. Customer service is A+ Very happy with the fitted wardrobes and work done.

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.