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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Anamorphic & Co. Ltd.
Rating: 1 out of 5
Extension Builder in Harefield
Anamorphic & Co. Ltd (FMB Certified), the company behind CasaVera Luxury Interiors, is a West London-based construction and interiors firm with nearly 10 years of experience delivering high-end residential and commercial projects across London, Surrey, Berkshire, Hertfordshire and surrounding areas. Our Construction Services - Full house build or refurbishments - Kitchen and rear extensions - Loft conversions - Bathroom installations - Flat and HMO fit-outs - Multi-unit residential developments - Single-room refurbishments - Structural works - Project management What makes us genuinely different is that through CasaVera we supply and install our own bespoke interiors from our 8,500 sq. ft Experience Centre in West London. Everything is manufactured to order and fitted by our own team - no middlemen, no third-party markups, just quality at a fair and honest price. Our Interiors Range - Kitchens - Wardrobes - Bathrooms - Lighting - Internal Doors - External Doors - Wall Panels - Flooring - Staircases Spindles and Handrails - Furniture - Home Decor We are a firm built on trust, accountability and repeat business. The majority of our clients come through referrals, and that says everything about how we work. Company No. 12784775. Fully insured with public liability cover.
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Latest review:
Restoration & Refurbishment- 10 Jul 2026
Never answered any messages after saying they would do the work. Would not recommend.
Ceca Developments LTD
Rating: 5 out of 5
Extension Builder in Harefield
Hael Construction Ltd, a proud member of the Federation of master builders, is a trusted construction company based in North London, delivering high-quality building services across the region. We specialise in new builds, extensions, loft conversions, renovations, groundworks, electrical installations, and plumbing. With a skilled team of qualified tradespeople and experienced project managers, we provide a complete service from design to completion. Our focus is on quality workmanship, transparent communication, and delivering projects on time and within budget.
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Latest review:
Extensions- 23 May 2022
Ceca Developments have done an outstanding work on our side and rear extension project, and we would definitely recommend this company. Firstly, they have offered a really competitive quote for the work and have been very transparent and detailed in regards to how long it will take to complete the project. Sebastjan has been a pleasure to deal with and was very helpful during the project, providing honest and useful recommendations and being available every time we needed anything. All the work has been completed to a very high standard and to the agreed timelines. We did not have to worry about anything during the whole project, which made this a very pleasant experience.
UK NAMA Constructions Ltd
Rating: 5 out of 5
Extension Builder in Harefield
Garden Fencing, Garden Decking, Artificial Grass, Wooden Floor Laminating, Decorating, Partitions.
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Latest review:
Carpentry- 1 Sep 2026
Ali did a great job from start to finish and will definitely invite him back in the future!
D Bird carpentry and building LTD
Rating: 5 out of 5
Extension Builder in Harefield
Hi were Dbird Carpentry & Building we are a family run company by myself Daniel and my brother Ellis. We take pride and love what we do! We will help you every step of the way through your project no matter the size.
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Latest review:
Conversions - General- 21 Jun 2022
D Bird Carpentry completed the works on time and to a high standard. Dan and his team were a pleasure to work with and I would be happy to work with them again.
linas builders
No reviews yet
Extension Builder in Harefield
team of all trades with lots of experience in building industry. we only employ professional tradesman. Can provide reference by request. Honest, price competitive
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Johal builders
No reviews yet
Extension Builder in Harefield
Hi I’m jagjit johal we r doing excellent work house extension and loft conversion i have 20 years experience for building works
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Alpha Construction & Development Group Ltd
Rating: 5 out of 5
Extension Builder in Harefield
Alpha Construction & Development Group Ltd offer bespoke service with a focus on the needs of our customers. We deliver one project at a time, without delays and stress-free. From small to big projects, we strive for the highest quality of work. We specialise in but are not limited to new builds, extensions, lofts conversions, structural works, roofing, plastering, rendering, painting and decorating, renovations, kitchen and bathroom fittings, pavings, brickwork, plumbing, full refurbishments.
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Latest review:
Bathroom Fitting- 25 Feb 2022
This was the best experience I have ever had with a team of builders. Aldo and Leo were polite, organised and their workmanship is of a very high standard. They replaced the bathroom in our rental flat, and it looks really smart. They also refurbished the kitchen, replacing flooring and decorated the whole flat. We have just shown it to an estate agent as we are planning to sell it and they were very impressed. Aldo was very helpful in making suggestions of small changes that would save us money and delivered the project on time and right on budget. Would recommend them and will certainly use them again.
M&I builders
Rating: 4.7 out of 5
Extension Builder in Harefield
M&I Builders Do it once,do it right! With over of 15 years of experience we can offer the package to provides stress free, time saving and cost effective solution to our clients to make the renovation project as easy as possible, with clear costing and progress plan..We are fully insured and considerable trade people fully qualified by BS to make your project up to current Standards. Your home is very important to us and measures we take to protect it is in the highest standards.
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Latest review:
Tiling- 24 Jul 2024
Job done perfectly, both builders are very professional, they care about the work and very experienced. Everything went smoothly with the tiling and flooring. They even installed extra kitchen cupboards:) Thank you both. I will be in touch for other jobs in the future. And recommended to my family
Franzosi Brickwork
No reviews yet
Extension Builder in Harefield
Newly qualified bricklayer after 3 year apprenticeship looking for small jobs.
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Armadillo Contractors
No reviews yet
Extension Builder in Harefield
Welcome to Armadillo Contractors! We are a privately-owned construction company offering carpentry and building solutions from start to finish. With over 30 years of experience in the industry, we are specialists in all aspects of general building and carpentry related works, extensions, conversions and decorating for both private and commercial clients.
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Amrit pal singh
No reviews yet
Extension Builder in Harefield
I am very Hard work and kind loyal and go to work daily and only take breaks on Sundays and start jobs at 8:00 o'clock and end at 5:00 o'clock at Late afternoon.
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john waller
Rating: 1 out of 5
Extension Builder in Harefield
father and son business both have cscs cards for bricklaying also do extensions and any building works ,i am a c.s.r.t (certificated surveyor in remedial treatments ) for damp and timber treatments,we have many years experience in the building industry,we have gained a good understanding of all the trades and have a good web site for you to view photos of our past projects .
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Latest review:
Damp Proofing- 20 Feb 2019
Said the damp would not be occurring after the damp treatment and gave a 10yr guarantee but it still keeps comming after 3 months of damproffing even though was given a 10 yr guarantee.
Atika
No reviews yet
Extension Builder in Harefield
As the Director of our Family business Atika Construction, I have been in the Building industry for over 8 years and was trained by a contractor who had over 25 years experience. I also have past experience in the carpentry trade. Myself and my partner have undertaken all different types of building and landscaping work.
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Ss construction
No reviews yet
Extension Builder in Harefield
With over 20 years of experience in the construction industry, our company has built a strong reputation for delivering high-quality projects with reliability and precision. We specialize in residential, commercial, and renovation projects, ensuring every build meets the highest standards of craftsmanship, safety, and durability. Our dedicated team works closely with clients to turn their vision into reality while completing projects on time and within budget.
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Joe Hilley
Rating: 5 out of 5
Extension Builder in Harefield
St Albans Brickwork specialise in all elements of residential and commercial brickwork construction projects. Our skills cover a wide-range of projects, home extensions and renovations, driveways & patios, garden walls, repointing, garage conversions and large building contracts. With more than 15 years’ experience in constructing new homes and delivering home improvements throughout St Albans, we are well equipped with the expertise to complete any size job to the highest possible standard.
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Latest review:
Repointing- 29 Jun 2017
Joe did an excellent job with our garden steps, despite the fact that we initially messed him about with timing of the job. He got the work done by our deadline, to a high quality, and for a good price. Highly recommended.
Kiseld
No reviews yet
Extension Builder in Harefield
Hi, i am a solo trader with 5 years experience in construction, I have a very good knowledge on everything that includes extensions, roofing, full flat refurbishment and good knowledge on other fields too, i looking forward to work for you.
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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.