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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JCL Renovations Ltd
Rating: 5 out of 5
Extension Builder in Harefield
We are a construction with over 20years experience between the team, We undertake all aspects of renovation work including house renovations and extensions. We also have extensive experience in laminate, hardwood flooring and decking installation. We offer a solution for any projects from start to finish all in one place.
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Latest review:
Repointing- 23 Jan 2020
Job well done. Will definately use in the future.
Scarlet developments limited
No reviews yet
Extension Builder in Harefield
Hello we are Scarlet Developments, we are a small family run electrical and construction company situated in Watford / Hemel Hempstead that has been established for 10 years.
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Israel torres
No reviews yet
Extension Builder in Harefield
Tiling, painting, block layer, drywall design,
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Timeless finishes ltd
Rating: 5 out of 5
Extension Builder in Harefield
With over 15 years in the construction industry, I have honed my expertise in managing both domestic and commercial projects. I thrive in high-pressure environments, where my skills in project management and quality assurance lead to successful, on-time project completions. I'm dedicated to sustainable practices and mentoring upcoming professionals in the field.Leading construction firm specializing in both residential and commercial projects. Managed multiple construction projects, overseeing budgets and ensuring projects were completed on time. Implemented quality control procedures that led to a 20% reduction in rework. Coordinated with subcontractors and suppliers to maintain project flow efficiently.Construction company focusing on residential buildings. Conducted site assessments and prepared reports on project feasibility. Supervised daily operations on site, ensuring adherence to safety standards. Fostered relationships with clients that resulted in repeat business
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Latest review:
Carpentry- 30 Dec 2025
Did the skirting across the whole house and the wood paint. Did a really good job! Would recommend.
Ferrity Construction & Home Improvements
Rating: 5 out of 5
Extension Builder in Harefield
Ferrity Construction is a Hertfordshire-based construction company delivering high-quality workmanship across a wide range of projects. We pride ourselves on a professional approach, attention to detail, and completing every project to the highest standards. Our areas of expertise include: - Insulation and thermal efficiency works - Retrofit solutions - Full home refurbishments - External Wall Insulation (EWI) - Roofing - Rendering - General building services - Patios - Electrics - Plumbing - Maintenance and repairs
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Latest review:
Restoration & Refurbishment- 27 Mar 2026
Excellent job to board out garage and lay flooring. Very professional, good value, highly recommended.
Construction
No reviews yet
Extension Builder in Harefield
Luxury Punjab construction Ltd And I all building work
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Carry on laying
No reviews yet
Extension Builder in Harefield
My name is John,I’m 43 and live in Watford I have been bricklaying/landscaping for 23 years now. I have a good friendly team of professional tradesmen who are reliable and very hard working Over the years we have been involved various small and large projects,varying from garden works to new builds.we are also lucky enough to have been part of a number of film and media projects 🎥 We love what we do and always compete jobs to a high standard,we take great pride in every job we are lucky enough to be involved in
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Maxmar Construction Ltd
Rating: 4.7 out of 5
Extension Builder in Harefield
We are a company that pride ourselves on taking excellent care of the ‘whole project’, from design to completion. We can, on your behalf, manage your project, coordinating all the required trades to turn up as and when required, leaving you to get on with daily life. Your dream home could be closer than you think, allow us to turn your ideas into reality. My company has lots of experience working on many different projects, big or small! On a personal level I am a honest hardworking individual. I have a lot of experience in all aspects of building work. I am familiar with building regulations and used to dealing with building control officers from the various local authorities. I have a fully skilled team of builders who cover all types of general building maintenance including kitchen and bathroom fitters, plasterers, flooring specialists, painters and decorators. The company offers a fully insured and guaranteed comprehensive
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Latest review:
Conversions - General- 21 Jul 2013
Flooring & lighting to extension not completed appropriately and resulted in later problems.
Simonmastermfp
No reviews yet
Extension Builder in Harefield
Hi My name is Szymon and I have many tears of experience in the profession 14 years. I am responsible person who will do the work accurately and cleanly.I have references and photo of the wirj performed. I am waiting g for proposals for cooperation.
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Manmeet construction and design
No reviews yet
Extension Builder in Harefield
“Resourceful builder with 5 years of experience in roofing, tiling, bathrooms, kitchens, floor fitting, painting, and garden constructions. Skilled in multi‑trade tasks from renovation to decoration. Known for precision, reliability, and delivering high‑quality workmanship under tight schedules.”
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Amritpal singh
Rating: 4.5 out of 5
Extension Builder in Harefield
We are here to assist you and provide you the work you dreamt off on very reasonable prices so trust us with your house and we will do the best for you .please do understand that we have to pay to get contact details of customers so it’s important being a customer to check the portfolio before short listing a tradesman just to be sure that we won’t just be paying for nothing .
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Latest review:
Extensions- 4 Jan 2026
I hired Amrit based on positive reviews, but my experience was extremely poor. The work showed all the signs of a cowboy builder. I’m sharing this to help others avoid the stress, delays, and financial risk I went through. 1: No Respect for Contract or Deadlines Contract deadline was 15th September, which he completely missed. Despite delays, he demanded money almost daily. When I referred him to the payment and work schedule he signed, his response was: “I didn’t read it, I just signed it.” 2: Dangerous and Unprofessional Working Practices Brought in unqualified workers, many of whom could not speak basic English. He ignored safety standards throughout the project and wanted to use the same unqualified workers for gas work, which is extremely dangerous. When I objected, his response was: “Don’t worry, you will get a new house if it blows up as you have insurance.” 3: Work failed multiple building control inspections. He eventually refused to cooperate with the building inspector.
Delta Construction Limited UK
Rating: 5 out of 5
Extension Builder in Harefield
We are commited to our clients. We have experience in working with bespoke clientele and are very confident in our capabilities, expertise and delivery of final product as well as after care.
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Latest review:
Decking- 23 Apr 2025
I needed someone reliable and efficient. Artan responded quickly to messages, was very polite, hard working and cleaned the area after the job. Stress free experience for me which was fantastic. Would recommend and definitely hire again. Thank you so much Artan!
Gary newall
No reviews yet
Extension Builder in Harefield
Our business undertakes works from building a garden wall to plastering a bedroom ceiling, after taking both brickwork and plastering to advanced craft in city & guilds, working on the tools in uk , Australia and Germany for over 25 years, partner in a company building our own projects, I now enjoy being back on the tools knowing the quality of work being produced, working along side a small, very highly skilled group of trades I’ve know for a long time…
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SM10 Studio Architecture
No reviews yet
Extension Builder in Harefield
We are a refreshing and talented team based on the outskirts of central London. We are truly passionate about buildings and are happiest when designing them. We pride ourselves in adopting a fresh approach and our skills extend to designing all types of building. We believe in providing tailored solutions for each and every project and ensure we maintain communication with our clients throughout the process. We offer a bespoke service ranging from planning and building regulations
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RT Build
Rating: 5 out of 5
Extension Builder in Harefield
We are a family run small company with 20 years on the market.We specialize in bathroom ,kitchen and general building refurbishments.We offer high quality service for a reasonable price with great attention to details. Your satisfaction is our top priority.We are looking forward to doing new project with you.
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Latest review:
Bathroom Fitting- 27 Dec 2025
Rafal did everything as expected. Many thanks for his commitment and professionalism.
Home & Garden Construction & Refurbishment
Rating: 5 out of 5
Extension Builder in Harefield
We are team with over 20 years experience with qualifications in construction industry. We are trust build for customers based on detailed estimates and fair prices for carrying any jobs, free estimate and skilled advising. Any jobs undertaken are proved by Gas Safe and electrical NICEIC certificates as also workmanship warranty by NVQ qualified skilled workers. Please see ours previous customers reviews and completed works. Please feel welcome to see my website.
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Latest review:
Conversions - General- 3 Apr 2025
We recently had extensive building work carried out in our kitchen, including alterations to a window and door opening, fitting new doors, installing a new kitchen, and completing decoration works. From start to finish, the experience was excellent. The quote provided was exceptionally detailed, outlining the full scope of work, a clear timeframe, and a draft contract. It was also very competitive compared to other quotes we received. The work was completed even quicker than expected, thanks to Pawel, the highly organised team leader. He and his team worked incredibly hard, ensuring we were involved throughout the process to accommodate all our needs. Their attention to detail and professionalism were outstanding. The final result has exceeded our expectations – the kitchen looks amazing! We highly recommend Pawel and his team for their expertise, efficiency, and dedication to delivering high-quality 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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Easily find verified local tradespeople. Just post your job to get quotes from tradespeople near you across the UK.

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.