Extension Builders in Harefield

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 Harefield

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13-13 BUILDERS LTD
Rating: 4.5 out of 5
Extension Builder in Harefield
I do plastering, plaster board, carpentry, partition, roofing, groundwork’s, driveways, gardening, extension, loft conversions
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Latest review:
Carpentry- 25 Apr 2026
Very helpful, fixed my front door sill and other odd jobs around the house. Would call again and good quality
Antal karoly
Rating: 4.5 out of 5
Extension Builder in Harefield
We are in the construction market since 15 years now covering all trades as being general constructors. We do loft conversions, extensions, full house refurbishment, bathroom and kitchen refurbishment, garage conversions and many more. We are a customer focused people as they happiness and satisfaction makes us proud of what we do.
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Latest review:
Restoration & Refurbishment- 3 Dec 2024
Antal was very punctual and explained everything about the job before commencing with the job. Antal and his team got the job done within the requested budget and with quality work.
BOTNARI CONSTRUCTION
Rating: 4.4 out of 5
Extension Builder in Harefield
We provide a service of maximum quality and client satisfaction . Having over 25 years experience in the field we have completed jobs big and small to the best standard .
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Latest review:
Electrical- 26 Jul 2026
Genuinely one of the worst builders we have come across. David rewired the flat and Stefan plastered the hallway. David is NOT qualified as an electrician and cut corners wherever he could. David leveraged us for money mid job and in the end left the job without finishing and without providing a certificate. David ran cables behind door frames (awful idea), got the cheapest material, forgot where holes were for spotlights and switches among many issues which meant we had to constantly ask our builders to fill the holes and make good. Stefan did the hallway plastering without putting on mesh. The plaster cracked within 2 weeks and the paint keeps cracking and will be a constant problem. When asked to come back and fix the issue - he point blank refused. They were the cheapest quote but we really hope we had gone to someone else
Ken Meyon
Rating: 5 out of 5
Extension Builder in Harefield
I have been a multi trade carpenter for over 40 years , and have had experience in the construction industry since the age of 16, which has helped me build my skills through hands on experience. I take a lot of pride in my work to insure everything is done to the highest standard, I take great pride in delivering high quality workmanship, attention to detail, and extremely reliable service.Throughout my career I have developed a wide range of skills across carpentry, property maintenance, renovations, repairs, and general building work. My services include carpentry, kitchen and bathroom installations, tiling and flooring, plastering, painting and decorating, plumbing ,and roofing repairs.
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Latest review:
Carpentry- 3 Jul 2026
Ken did a brilliant job fitting my new living room door. His workmanship was excellent, and the finish is perfect. He was professional, reliable, and a genuinely down-to-earth, friendly guy to deal with throughout the whole process. His pricing was also very reasonable, offering great value for the quality of work provided. I’m extremely pleased with the result and wouldn’t hesitate to use him again. I would highly recommend Ken to anyone looking for a skilled, trustworthy builder. Thank you for a fantastic job!
SS Carpentry
Rating: 5 out of 5
Extension Builder in Harefield
I have done jobs from shelving to roofing.I have a good job knowledge and I have ran big site. I have been a carpenter for 6 year and normally do first fix work but I can do second fix , kitchen fixing and plasterboard. I have all the tools to do the jobs with.
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Latest review:
Carpentry- 28 Aug 2018
Steve is punctual, easy to work with, hard working with all the skills, knowledge and experience to efficiently produce a successful result- replacing old floorboards and removing squeaks in steps- recommended and known from this job alone.
H P JONES BRICKWORK LIMITED
Rating: 5 out of 5
Extension Builder in Harefield
With over 15 years experience, H P Jones Brickwork Ltd prides itself on providing a trustworthy and efficient service to the highest standard. We understand having work carried out can be stressful. But whilst providing you with top workmanship throughout your project, our team aim to keep disruption to a minimum. Customer care is paramount in our service and we believe that regular communication with our customers is key to ensuring they are happy with the service provided.
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Latest review:
Harry was a wonderful contractor to use. Polite, friendly, kept us informed on how the work would take and how it was progressing. Extremely professional, I wouldn't hesitate in using him again and recommending him to family and friends.
Sebastiano Vuksani
Rating: 5 out of 5
Extension Builder in Harefield
Build your dream with SV building construction ltd Regards
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Latest review:
Extensions- 30 Jan 2023
I had the pleasure of having them carry out a single story extension and fibreglass new roof of my property. I found they always turned up when specified and carried out fantastic quality work for a competitive price. Not being a builder you have to place trust in a person / company. They always made sure that we were happy keeping us updated with the project every step of the way. They were kind and considerate to our neighbours making sure they were not loud early in the morning or late in the evenings making the whole process run smoothly. I can not stress enough how great these guys are. Thanks
Pardeep Hunjan
Rating: 4.9 out of 5
Extension Builder in Harefield
Experienced builder for all types of work, prioritising quality and customer satisfaction above anything else
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Latest review:
Bathroom Fitting- 31 Jul 2025
Highly recommended. Great communication, clean, punctual and honest.
M&C Company
Rating: 5 out of 5
Extension Builder in Harefield
I am a very hard and an experienced handyman.I and my team have done a lot of renovation work all-over London. My main trade is Painter&Decorator.No job is little or to hard.Most of the projects are done in time and on the budget.
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Latest review:
Painting & Decorating- 5 Sep 2021
Muhamet was very professional and delivered the job on time and in high quality. I would definitely recommend him.
Sweet Home Construction
Rating: 4.4 out of 5
Extension Builder in Harefield
We are professionals in extensions (side double story, rear single story, side and rear single story and loft conversion. We also deal with refurbishing the whole house as per requirements of the customer.
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Latest review:
Extensions- 2 Oct 2018
Completed Side extension and 6m rear extension last Oct. Overall happy with the work. Digging, foundation, Bricks, structure, insulation, Roofing, Tiles, plumbing, flooring, painting, etc were done to good standard. Some of the minor corrections, changes or fixes needed near completion were done accordingly. Quote was in midrange and reasonable compared to compared to some others I received. Raman is very easy to work with and clear in his communication. Never had any issues all through construction through to finalising stages. Would recommend Raman to others.
Bathroom Renovation
Rating: 5 out of 5
Extension Builder in Harefield
Im a multi trader and have a wealth of experience in construction on large projects and sites. We do bathrooms, kitchens, plastering, flooring, general renovations and extensions. We ensure we exceed clients expectations go above and beyond and work with a high standard and quality.
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Latest review:
Plastering- 8 Jun 2026
We were thoroughly pleased with Bathroom Renovation, Bahram and the services provided. We required stud walls throughout our apartment, ceiling replacement and ducting/pipework concealing. I can only say that Bahram and his communications have been a breath of fresh air. The team are efficient, friendly and get the job done - most importantly Bahram takes pride in the work his team complete. Our job was relatively urgent and Bahram offered what I feel was a fair price, remained communicative and had his team readily available to get the job completed within the timeframe. Most importantly, as with it seems all building works, jobs can grow slightly, but Bahram’s considered approach and advice was invaluable. We increased the scope of our works mid-job, and are really pleased with the results. Fair pricing, someone who has pride in their work, and a job well done.
Saryal Construction Ltd
Rating: 4.9 out of 5
Extension Builder in Harefield
A team of skilled and experienced workers operating efficiently and producing effective results that are appealing and catered to customers' needs. Non-VAT company. Competitive prices benefit. Feel free to get in touch for full house refurbishment or part refurbishments like bathroom/kitchen/bedrooms. Other project we take on are garage conversions, and projects like tiling, carpentry, roofing. https://linktr.ee/saryalconstruction
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Latest review:
Bathroom Fitting- 2 Aug 2026
The team did a brilliant job and completed everything in one day. A good price too. Great attention to detail and skilled workers.
Ash Managing Investments Ltd
Rating: 5 out of 5
Extension Builder in Harefield
Ash Home Renovations turn your dreams into reality and achieve complete client satisfaction by understanding, designing, creating and building your vision in the most cost effective way, with a quick turnaround. One company does it all. All work undertaken is fully insured and guaranteed.
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Latest review:
Quality of the workmanship has been to very high standard, we are extremely pleased with the end results. During thr project, the team often came with ideas and recommendations along the way. The team clearly have a lot of experience and are well organised.
B&G Brothers Construction Ltd
Rating: 4.8 out of 5
Extension Builder in Harefield
WELCOME TO B&G BROTHERS CONSTRUCTION LTD B&G Brothers Construction Ltd is a well-established building company based in Stanmore North West London. We carry out most types of building works, including: House Extensions Property Refurbishments Loft Conversions Ground Works And all type of repairs and alterations. You can be confident in our abilities to create you that perfect home using the highest quality of materials and best possible level of workmanship
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Latest review:
Extensions- 11 Jan 2023
Rear garden extension done with new fully refurbished old house new electric new plumbing, all work done properly and good quality, experienced builders , +++ big job done within time frame and olso garden levelling with retaining wall ! Andrei and Alex recommend!
Mantas Gurskas
Rating: 5 out of 5
Extension Builder in Harefield
Little jobs and larger projects.
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Latest review:
Demolition- 21 Apr 2021
Mantas was really helpful and hard working.A great job,thankyou.
White Van Construction
Rating: 5 out of 5
Extension Builder in Harefield
White Van Construction is your trusted all in one building company, delivering high quality workmanship from start to finish. We undertake all aspects of building work including tiling, carpentry, plumbing, electrical work, renovations, extensions and much more. No job is too big or too small. With years of experience, including building homes from the ground up, we take pride in providing reliable, professional and efficient service tailored to your needs. We can also source all materials and manage the entire process for you, helping to take away the stress and headache of your project. At White Van Construction, customer satisfaction is our priority. Contact us today for a free quote and let us bring your vision to life.
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Latest review:
Carpentry- 31 May 2026
Work went really good . On time and well communication. Definitely deserved five stars.

3.9

Top rated Extension Builders

Our Extension Builders in Harefield, 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 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.