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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BS construction
Rating: 5 out of 5
Extension Builder in Harefield
Hi, I’m brar I’m working from last 8 years I’m construction field I’m expert in whole building work special extension, roofing, pvc window door glass, flooring, paints etc. thanks.
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Latest review:
Windows & Doors (uPVC & Metal)- 3 Feb 2025
The job was done professionally and we are happy. I would recommend BS construction
KACA CONSTRUCTION LTD
Rating: 4.8 out of 5
Extension Builder in Harefield
Kaca construction Ltd is a prospective, family run building company based in London . We supply high quality services in residential construction field. We work closely with our customers, designers and architects to make sure we meet the clients’ expectations. We listen, understand and deliver what the client wants from the point of the planning to the point of delivering your dream home. Our team is offering all the general building work, we specialize in extensions, lofts, exterior and interior work. we have complete team of professionals including architects, engineers and designers to provide end-to-end services, also we can help with applications for the local authorities and building regulation services. All work is fully insured and guaranteed for your peace of mind. We pride ourselves in a great customer service and our reliability. So if you're looking for a construction company in London with many years’ experience in the construction trade then look no further than Kaca Construction Ltd. Whether it’s a query or a quote we would be very happy to assist you. We cover all London area and near by .
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Latest review:
Extensions- 19 Nov 2019
We have found Kaca Construction to be a reliable and trustworthy building company with good quality workmanship. The director Elson was always available to address any queries and was responsive to our needs. Kwesi and Ros.
NAIL & SCALE
Rating: 5 out of 5
Extension Builder in Harefield
Nail and Scale is a reliable and professional handyman and property maintenance company providing high-quality repair, maintenance, and improvement services for residential and commercial properties. We specialise in general handyman work, including carpentry, minor plumbing and electrical repairs, painting and decorating, furniture assembly, installations, and general property upkeep. Whether it’s a small repair or ongoing maintenance, Nail and Scale delivers efficient, affordable, and high-standard workmanship. Customer satisfaction is at the core of our service. We pride ourselves on being punctual, tidy, and detail-oriented, ensuring every job is completed safely, professionally, and with minimal disruption. At Nail and Scale, no job is too small — we are committed to keeping your property safe, functional, and well-maintained.
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Latest review:
Handyman- 6 Jan 2026
Firstly, I havent used mybuilder in years, and I hired Zaim hoping for a good job on our dining chairs. I can safely say I was very suprised. He did an excellent job. From the moment we talked he had great communication, he was timely and said he would call 30 mins before arrival which he did, he spent time fixing the legs of the chairs as if he were doing the work in his own home. He is also not afraid of letting you watch him work, he has nothing to hide and is genuinely a nice person. He wants to do a good job and doesn't leave until the room is in the condition it was in before he came, he even hoovered up afterwards. Zaim was professional, calm and knowledgeable. Some people do a rush job, but you could see he wanted to do a job that was good, even redoing work because he wasn't happy with it. A solid job. Would certainly recommend.
Jason S Rogers
Rating: 5 out of 5
Extension Builder in Harefield
With 19 years experience I specialise in boiler installations, Landlords gas safety certificates and gas emergencies. I am a Worcester Bosch accredited installer but I also fit all other makes of boiler. I listen carefully to customers requirements and always carry out every job to strict safety standards. My rates are competitive and all quotes and advice are free with no call out charge
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Latest review:
Gas Work- 7 May 2019
Jason was a breath of fresh air. He is highly professional, totally ethical and has great integrity. Unlike many engineers who took no time in quoting me for a brand new boiler,Jason checked the boiler to accurately ascertain what precisely was wrong with it in order to determine whether a new boiler was necessary at all. He identified the problem to an external loose valve above the boiler which was leaking. He kindly tightened the valve and stopped the leak. My sincere thanks to Jason for saving me in excess of £3000.00!
NDR PROFESSIONAL LTD
Rating: 5 out of 5
Extension Builder in Harefield
Plastering, Silicone render, plasterboard...
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Latest review:
Plastering- 29 Aug 2025
I asked Daniel to check and price some pebble dashing job. Daniel was fair in his pricing. He was on time in commencing the work as we had agreed. He never left the site until the job was completed within a few days, hence causing least interruptions. I do recommend him and I intend to ask him to carry out works in future.
GpmBrickwork ltd
Rating: 5 out of 5
Extension Builder in Harefield
GpmBrickwork Ltd Extension garden walls all types of Brickwork Patios Chimney repairs New builds
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Latest review:
Bricklaying- 8 May 2026
Gordon was amazing. He came within a few days on a weekend to repair the steps as they were dangerous. He did a great job, also repairing loose brickwork on a wall at no extra charge. Very reasonable price too. I can recommend him and will definitely contact him again for brickwork jobs.
HR RENOVATIONS
Rating: 5 out of 5
Extension Builder in Harefield
HR Renovations cover all aspects of building renovations.
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Latest review:
Painting & Decorating- 2 Jul 2025
Would highly recommend HR Renovations. A massive thank you to Ben and his team. They did a fantastic job of renovating my house and I would definitely be using them again! I would highly Recommend HR Renovations.
360Build Solutions Ltd
Rating: 5 out of 5
Extension Builder in Harefield
360Build Solutions Ltd - specialised in Extensions (single or double storey), Conversions - Loft, Garage, Full Refurbishments including Kitchens, Bathrooms, Home Cinema and complete New Builds - Home Office, Gym. We deliver top quality of work and we always look at many options to come to the most logical and profitable solutions for our clients and to build long and lasting relationships. Free site visits and Estimates - learn more about us in About...
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Latest review:
Extensions- 17 Nov 2019
Marius is the best builder ever! I can not recommend Marius enough, if he can do your job I would bite his arm off! He and his team are hard working, efficient and tidy. Nothing was too much trouble, the job barely ran over schedule and I now have the most fabulous new home! This is the way building work should be done!!
Mapna constraction ltd.
Rating: 4.2 out of 5
Extension Builder in Harefield
Hi everyone, We are a family-run business with over 10 years experience and pride ourselves on our incredibly high-standard quality of work, customer rapport, competitive prices and efficient time-frames. With our customers' satisfaction held in the heart of our work, we will go the extra mile to ensure all needs and requirements are met and you are 100% satisfied with the end product. 'If it isn't good enough for our home, then it isn't good enough for yours'.
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Latest review:
Bathroom Fitting- 8 Apr 2026
Arash and the team were great - on the job on time every day - flexible in regards a lot of the fittings and adjustments. Very good price and work completed on time. Monies all agreed upfront, payment in part as based on progress. Will use again.
karam traders
Rating: 4.9 out of 5
Extension Builder in Harefield
All domestic and commercial Electrical and Plumbing work and maintenance and Repairs Painting and Decoration Laminated Flooring and Lino Sheet ( Vinyl ) Garden Fencing and Gardening Tiling, renovation bath and kitchen and all maintenance around property
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Latest review:
Handyman- 31 May 2026
Thank kashif for doing a great job , I would recommend it and use his services in future
West Renovation
Rating: 5 out of 5
Extension Builder in Harefield
When you need a reliable building company to renovate, refurbish or extend your property our skilled teams of experienced craftsmen are ready to help you. From elegant extensions or conversions, kitchens and bathrooms to complete house renovation we can provide a tailor-made service to suit your budget and requirements! *MyBuilder does not check company descriptions. If you think
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Latest review:
West renovations did renovation works at my property, the staff members were professional, skilled and polite people. They paid attention to every detail and the finish was more than what I had expected. They answered any questions that I had and actually took care in the work they did. I've recommended them on to all my friends and family and will certainly contact them again if I need more works done in the future. Thank you to everyone
OWA CONSTRUCTION LTD
Rating: 4.9 out of 5
Extension Builder in Harefield
We are a medium sized groundwork company based in West London. We have over 18 years groundwork experience. We specialise in Drainage , Basements Reinforced concrete, Foundations, Block and beam , Paving , Fencing Etc . We pride ourselves in our work and customer satisfaction is our top priority.
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Latest review:
Groundwork & Foundations- 7 Feb 2026
Oli carried out the groundworks and demolition at my property and was on site every day with his crew, fully committed and hands-on throughout the job. I am an architect, and this was work on my own home, so my expectations were high. Oli met those expectations fully. He has a strong knowledge of groundworks and demolition, works carefully and methodically, and you can tell he genuinely enjoys what he does and takes real satisfaction in delivering the work exactly as required. He was always in a good mood, easy to communicate with, and a pleasure to have on site. I enjoyed discussing the project and hearing about other jobs he has completed over his 23 years of experience, which clearly shows in the quality of his work. I would highly recommend Oli for any groundworks or demolition works.
Asen Terziev
Rating: 5 out of 5
Extension Builder in Harefield
I have been working in construction since I was 19.I have qualified as external wall insulation,rendering and plastering!Over the years I have undertaken bricklaying and roofing jobs as well!
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Latest review:
Plastering- 7 Oct 2022
Excellent work, very professional.
Fitzgerald Construction
Rating: 5 out of 5
Extension Builder in Harefield
We are a small group of tradesman who have worked together for the last 25 years. We have extensive experience in all types of domestic building work and specialise in open-plan kitchen/diner extensions (including the full structural steelwork supports).
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Latest review:
Bricklaying- 17 Jun 2022
Our brick garden wall was collapsing and I contacted Richard Fitzgerald for a quotation. I'd already had a few quotes from other builders, some of whom had told me I needed work doing that didn't need doing! I found Richard to be trustworthy. He provided a competitive quote. He managed to source bricks that matched the colour of the adjoining wall, gave us a detailed breakdown of the work he would do, and didn't ask for any payment in advance. He built a strong brick wall with a concrete support wall behind. The finished wall is excellent and we are very happy with the work he and his team have done. On finishing the work the premises were left clean and tidy. I am very happy to recommend him.
Bricklayer
Rating: 5 out of 5
Extension Builder in Harefield
Brickwork . New build, extension . Garage
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Latest review:
Bricklaying- 10 Jul 2023
I am very pleased with the work done Excellent clean job Mr Bicol has carried out
Nick
Rating: 5 out of 5
Extension Builder in Harefield
With 14 years experience in construction I undertake all kind of jobs: built, repairing and maintaining. I'm a reliable and a good communication person. Delivering great results within the planned time frame and budget is at the basis of what we do. We work closely with our clients, providing advice, discussing alternatives and taking on responsibility for the execution of all activities. We arrange orders, deliveries and returns of materials.
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Latest review:
Carpentry- 26 May 2024
Nick is fantastic and a highly skilled professional. I am very happy with his work. He communicated very clearly. He understood what I wanted and the end result went above and beyond my expectations. I am so happy I’ve found him and definitely using him for future work!

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.