Extension Builders in Harefield

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.1 (18 reviews)

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Some of our top rated extension builders in Harefield

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AMALGAM BUILDERS LTD
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Extension Builder in Harefield
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Cani 1 construction
Rating: 4.7 out of 5
Extension Builder in Harefield
we have a construction company we are in the happy position to fulfill each one separately our company is family owned we have been in this area for over 15 years, we offer (brickowork)🧱 face bricks face blocks garden wall retaining wall extension new building new house Repoiting landscape design & builds🏜
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Latest review:
Bricklaying- 16 Jun 2026
Cani and his team did a great job on my gable walls We struggled with the weather but they kindly worked late to ensure the project was completed on time to fit in with my other tradesmen. I am happy to be able to give them a 5 star review and would not hesitate in recommending Cani and his team to others.
Brick and mix construction
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Extension Builder in Harefield
At Brick and Mix Construction, we pride ourselves on delivering top-notch professional craftsmanship, backed by 25 years of experience in the building industry. Our experience spans both commercial site work & residential work.
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Tatla development ltd
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Extension Builder in Harefield
Specialising in all building projects including extensions, property refurbishment and building maintenance. we cover the wider London area.
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Zen Construction
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Extension Builder in Harefield
I’ve been working in the construction and property improvement industry for over 12 years, gaining hands-on experience across a range of jobs from full house renovations to smaller repair and maintenance projects. I’m based in London and cover surrounding areas. I specialise in Demolition, Carpentry, Bricklaying, Laminate Flooring, Extensions, Driveways, with a strong eye for detail, reliable workmanship, and a focus on delivering high-quality results. I take pride in being honest, hardworking, and easy to communicate with—clients know they can trust me to get the job done right the first time. If you’re looking for someone dependable, skilled, and committed to quality, I’m ready to help.
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H & F London Limited
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Extension Builder in Harefield
H & F London is a specialist construction company based in Hertfordshire & West London. We’re known for providing groundwork solutions & new builds for a variety of clients across London and Hertfordshire.
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Oakleigh building services
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Extension Builder in Harefield
Oakleigh building services is a well established, highly regarded building company. Covering all aspects of roofing and building works , Based in Surrey
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Raj Builder
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Extension Builder in Harefield
MyBuilder is a UK-based online marketplace and matchmaking platform that connects homeowners with local, reliable tradespeople (such as builders, plumbers, electricians, roofers, and other home improvement professionals. MyBuilder is a UK-based online marketplace and matchmaking platform that connects homeowners with local, reliable tradespeople (such as builders, plumbers, electricians, roofers, and other homes - **For homeowners**: Post a job for free (e.g., extensions, kitchens, bathrooms, roofing, gardening). The platform uses a matchmaking system to alert relevant, verified tradespeople in your area. You receive interest from tradespeople, review their profiles (including past work history, customer feedback, ratings, and references), chat directly, compare quotes, and hire the best fit. No fees MyBuilder is a UK-based online marketplace and matchmaking platform that connects homeowners with local, reliable tradespeople (such as builders, plumbers, electricians, roofers, and other home improvement professionals). Founded in 2018 by Raj (a stonemason and roofer frustrated with traditional ways of finding work), MyBuilder started as a simple idea to help consumers find trustworthy local builders and tradespeople more
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R&S construction services
Rating: 5 out of 5
Extension Builder in Harefield
I have been for 20 years now in building works i like what i do and i like make other people to have they dream house to make them happy
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Latest review:
Great service received. Called Martin out that day and he fixed my front door straight away. Great price and great service received will be using him again in the future.
Brothers construction
No reviews yet
Extension Builder in Harefield
I work 13 years landscape Groundwork all sort of job gardening extension loft conversion After this long time i ve decided to work for myself. I ve been working throughout UK
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GTF Brickworks
No reviews yet
Extension Builder in Harefield
Hello my name is George. I have 12 years' experience in all areas of brickwork including feature panels, extensions, garden walls, wall repairs and new builds.
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Redriver loft converters ltd
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Extension Builder in Harefield
Welcome to Red River Loft Convertors Limited At Red River Loft Convertors Limited, we specialise in transforming homes with high-quality loft conversions, house renovations, extensions, bespoke kitchens, and luxury bathrooms. From initial design through to final installation, we provide a complete, end-to-end service tailored to your needs. Working closely with experienced architects and structural engineers, we can guide you through every stage of your project. Whether you're looking to create additional living space, modernise your home, or undertake a full renovation, our knowledgeable team is here to offer expert advice and professional support from the very beginning through to successful completion. With a commitment to quality craftsmanship, attention to detail, and excellent customer service, we take pride in delivering beautiful, functional spaces that enhance both your home and your lifestyle.
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Viorel nicoara
No reviews yet
Extension Builder in Harefield
I have more than 15 years experience of the construction
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G&j
No reviews yet
Extension Builder in Harefield
I started my career as decorator in 2019 ,my goal is client satisfaction with a fair price and maintain the quality of my work which I intended to continue.
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Malkeet Mangat Roofing And Building Contractors Ltd.
No reviews yet
Extension Builder in Harefield
we are roofing and building specialist started in 2007, and it became a limited company in 2011. our company also do all type of building projects big or small. like loft conversion, house extension, house renovation and any type of building work. we also specialize in roofing work, pitch roof, slate roof, plain tile roof, all types of flat roof.
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FFernandesConstruction
No reviews yet
Extension Builder in Harefield
Fernandes Constructions Hi, we have been in this trade 10 years We specialise in: painting and decorating wood flooring full bathrooms, full kitchens, electrical & plumbing house extensions Conservatory
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4.1

Top rated Extension Builders

Our Extension Builders in Harefield, are rated 4.1 out of 5 based on 18 reviews from customers like you.

Quality screening

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.