Extension Builders in Harefield

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4 (17 reviews)

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Some of our top rated extension builders in Harefield

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Olgert Doko
Rating: 4.8 out of 5
Extension Builder in Harefield
My name is Olgert and my team and I are ready to give you a quote, on any building needs - painting, plastering, tiling, roofing, extensions and many other services. We are friendly, reliable and professional and we care about our work. Give us a call today for a free quote. We are located in North West London and we have more than 15 years experience in construction.
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Latest review:
Tiling- 15 Sep 2021
Very professional and helpful from the beginning to the end. Great work, tiling was finished on time and to a great standard. Our new restaurant floor looks great and customers love the new look. Would definitely recommend and will use again. Thanks Team Doko
Hsingh builders ltd
No reviews yet
Extension Builder in Harefield
I am professional builder with an experience of 17 years in the building industry and track record of successful projects . I am committed to deliver high standard of quality work which is completed on agreed time scale within the given budget. Starting from beginning till end, customers satisfaction is my priority , which is why I am able to turn visions into reality. You can really on us as our core values are- strong foundations, beautiful designs and lasting value. My vision as a builder is to build the dream house for my customers, so you can trust us in bringing architectural visions to life. You can rely us on as we do cater the needs of our customers, provide attention to every aspect and complete the work to high standards. We do discuss each step of the work with the customer and build a long lasting relationship with customers.
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SRK Constructions London Ltd
Rating: 5 out of 5
Extension Builder in Harefield
We offer a plethora of construction services and are known for excellent k-rendering, electrical fitting, plumbing, and carpet service. We have been in the industry for more than 14 years and our work varying from small to large projects speaks about our experience in the field. We believe in creating with heart and building with the mind. We are trustworthy contractors and always strive to meet the quoted budget. Clients’ satisfaction is the topmost priority of the SRK constructions.
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Latest review:
Bathroom Fitting- 12 Apr 2022
Sandeep was the first builder who I ever met who finished job before time . His team has worked very hard and did job as per our expectations . Before this I used 3 different builders and no one finished job on time . I will recommend him for any building related job .
Redmark Contractors Limited
Rating: 5 out of 5
Extension Builder in Harefield
Redmark Contractors Limited have over 10 years experience, and with many years experience in the building trade. We are a professional team are reliable builders operating in London and the wider area. We take great pride in all work which we undertake, taking great care to make sure that our client’s needs are met in a meticulous and professional manner.
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Latest review:
Extensions- 27 May 2025
They helped build me two houses and were always putting their best foot forwards. Bhupinder and his team are lovely, and are now like family to me. They have a bright future ahead for themselves and for the clients they look after.
Cocis Construction Group
Rating: 5 out of 5
Extension Builder in Harefield
Cocis Construction Group LTD is a family-run construction company with over 25 years of hands-on experience in the trades. We specialise in home renovations, extensions, bathroom and kitchen refurbishments, and property development across London. As a young, ambitious company, we combine traditional craftsmanship with fresh ideas and modern techniques to deliver projects efficiently and to the highest standards. Our team takes pride in attention to detail, clear communication, and building lasting relationships with homeowners, landlords, and property investors alike. At CCG, we don’t just build structures—we bring visions to life, turning ideas into beautifully finished spaces. Contact us today for a free quote and see how our expertise and dedication can make your next project a success.
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Latest review:
Cocis Construction Group done the full interior painting of our 5 bedroom house and we are really happy with the result. The team was polite and worked very hard every day. They kept things clean and finished everything on time like they said they would. The paint finish looks great and the whole house feels fresh again. Would definitely recommend them if you need painting done.
Kelleway Carpentry Services
Rating: 4.7 out of 5
Extension Builder in Harefield
Hi my name is Gary I am Carpenter & Joiner with over 25 Years Experience. I have traditional values with modern methods. I believe I am hard working reliable & Trustworthy. Trust & Respect are everything. I do General Building & what I don't do I have experienced Tradesman. Free Esimates.
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Latest review:
Carpentry- 25 Nov 2017
Gary completed the job promptly, his work is good and he left the premises tidy - also reasonably priced. I will be hiring him again.
Carpenter quality
Rating: 5 out of 5
Extension Builder in Harefield
CARPENTER QUALITY LTD •SPECIALISED IN EXTENSIONS •LOFT CONVERSIONS •BESPOKE CARPENTRY •KITCHEN & JOINERY •NEW BUILD & REFURBISHMENT
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Latest review:
Carpentry- 11 Jul 2026
Very hrlpful and professional. The new doors looks amazing! I am very pleased with the finish.
H & A Rail ltd
Rating: 5 out of 5
Extension Builder in Harefield
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
singhbuilder
Rating: 5 out of 5
Extension Builder in Harefield
Hi my name is Dil Singh, I'm a runing own business with 10years + experience, Multi skilled in all aspects of as a certified electrician, roofing and building.Able to deliver a high standard of work. All new work can be done guaranteed,References avalible on request. I done plenty jobs like electric work: change the consumer unit, wiring, design and inspection and testing, fault finding, loft conversion, extensions. I never let down my customers. Job done guaranteed from a to z by me.
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Latest review:
Electrical- 26 May 2021
Happy with replacement programmer. Dil came straight back the next day when there was a problem and rectified.
Bizy Construction Ltd
Rating: 5 out of 5
Extension Builder in Harefield
Welcome to Bizy Construction ltd, a construction company located on the western fringe of Greater London, committed to delivering an exceptional service on budget and on time. We have a dedicated team committed to delivering exceptional New Build, House Refurbishments, House Extensions, Loft and Basement Conversions to a specific budget, while ensuring we meet our clients' expectations.
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Latest review:
Extensions- 3 May 2022
Job done by Bizy Construction Ltd, Was done to the highest standard every team member was very polite and helpful. All the work was done using in house trade person nothing was contracted out so all the work went very smoothly. New kitchen/rear extension excellent. My wife and I are very pleased with all the work done by Bizy Construction Ltd, and would use them again. We would recommend them to anyone who need a reliable building/construction company. Zied was excellent give us advice and idea as if he was a private adviser. Which we appreciate and valued I can’t praise the workmanship enough or find any thing to complain. Thank the team that work on my property.
CONSTA Construction Limited
Rating: 4.6 out of 5
Extension Builder in Harefield
CONSTA Ltd - small construction company based in London, and characterises in flexibility to complete various jobs . There is list of different small or awkward completed jobs in our portfolio as well as more significant projects as loft conversions, extensions, full house reconstructions, new build and Passive House construction as well.
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Latest review:
Extensions- 29 Aug 2021
Communicated well at the start with reasonable cost. work was done well but the finishing was not so great as expected. The end cost was very expensive. Charged by the hour, the team were very slow which was upsetting to see me pay for time where they sat around not doing much. Ensure to agree fixed price. Communication after job is poor, double glazing has warranty which now not being able to communicate with kostas having to pay to get things done that should be covered in warranty. Central heating give huge problems. Do not use for big jobs
JC Building & Decorating
Rating: 5 out of 5
Extension Builder in Harefield
I offer all aspects of Building & Decorating• Home Improvements• General building • fencing • custom gates • fencing • Kitchens •Bathrooms •Tiling •Flooring •Doors •Garden Maintenance •Wallpapering •Flat Pack Furniture and more just contact me for anything and I will be happy to provide my services. My work will always be completed to the highest of standards and at extremely competitive prices by my Full team of professional tradesmen.. Please feel free to get in touch for a free quote
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Latest review:
Fabulous service. Came and provided an honest and competitive quote. Work completed quickly and as I wanted. Will look to use again in the future. Thanks
Vladimir paskov -general bulding
No reviews yet
Extension Builder in Harefield
General builder .handy man Ground worker. Steel beams installer
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Angle Construction
Rating: 4.7 out of 5
Extension Builder in Harefield
We have been in the construction business for over 15 years doing all sorts of works, from minor works to full home constructions. No job to small no job to big. We work in and around London
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Latest review:
Windows & Doors (uPVC & Metal)- 28 Jan 2026
Very unhappy with how things went with Angle Construction overall. Poor comms during the transaction was the first red flag - no communication for 2 days the moment money was sent, however afterwards received an apologetic call - parts ordered and arrived in due course. Andrei turned up, and got to work on removing the old gate, but then started shaving down the post without saying anything -we were told after that the posts were not level. Eventually he said the door would need to be cut, which we agreed to. The door and posts were both cut to fit, but massive gap left at the bottom, and only half of the door fittings and no handles were installed! In addition, where the door was cut and the wood shaved made, a lot of mess was left all over the garden furniture and patio floor. Shocked at the lack of care and professionalism. He was clearly agitated and in a rush to leave. We have a working back door, but it looks like a real botched job. Not happy, and I would not recommend.
iCAN Construction Ltd
No reviews yet
Extension Builder in Harefield
iCAN Construction is a passionate team of trustworthy qualified builders and experienced professionals. We pride ourselves on providing a first-class service alongside high standards of work. We specialise in: Extensions, Loft Conversion, Property Refurbishments, Bathroom Renovations, Property Maintenance and Groundworks Whether it is a kitchen, bathroom, or full house renovation, with our 20 years of experience and excellent reputation you can be confident your ideas will be joined with our craftsmanship to produce your dream home. Throughout these years ICAN Construction has gained a reputation as a quality renovator and a trusted contractor, which can confidently take on any projects anyone can have in mind. From concept to creation helping you build the home of your dreams.
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JKBC
Rating: 5 out of 5
Extension Builder in Harefield
By having 20 years of experience in the business, no job is too challenging. My team specialises in both small scale repairs and decorating, as well as major projects such as refurbishments, extensions, and home renovations.
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Latest review:
Jerzy carried out several jobs for us. He has completely refitted our bathroom, he's rebuild a wall, laid front of house path, restored old front door, installed solid wall internal insulation, rebuild window frames, plastered a room and few other bits and pieces. He is extremely reliable and trustworthy. He's always been on time, works really hard and has always been honest about things and up front with any issues. Always consulted us for possible solutions. His work is to the highest standard and if I want a job done well, I always go to Jerzy.

Top rated Extension Builders

Our Extension Builders in Harefield, are rated 4 out of 5 based on 17 reviews from customers like you.

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What types of services are offered by local extension builders in Harefield?

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 Harefield 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 Harefield who are available and interested can respond to your post.

Browse profiles, read customer reviews and get quotes from your chosen Harefield extension builders, all before you decide who to hire.

What are the hourly rates of extension builders in Harefield?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Harefield 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 Harefield extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Harefield home extension project is likely to cost.

Find extension builders in Harefield with MyBuilder

Hiring the right extension builder in Harefield 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 Harefield extension builders. Once your job is live, we’ll share it with home extension builders in Harefield who can express their interest.

Step 2: Compare different extension builders in Harefield

When you start receiving interest, review profiles of local Harefield extension builders, check their previous work, and read real customer reviews. Ask about timelines, materials, and request detailed quotes.

Step 3: Hire Harefield extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Harefield, 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.

Harefield extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Harefield extension builder before hiring?

Before hiring an extension builder in Harefield or extension building company in Harefield, 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 Harefield?

An extension builder in Harefield 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 Harefield 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 Harefield?

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 Harefield 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 Harefield 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 Harefield

Can an extension builder in Harefield help with planning permission?

Yes, many extension builders in Harefield 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 Harefield handle everything from design to construction?

Many Harefield 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 Harefield help with materials and finishes?

Yes, most extension builders in Harefield 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.