Extension Builders in Harpenden

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.3 (10 reviews)

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Some of our top rated extension builders in Harpenden

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JDL Construction
Rating: 5 out of 5
Extension Builder in Harpenden
JDL Construction Limited are a Hertfordshire based building company offering both domestic and commercial services. We specialise in all aspects of construction including Home Extensions, New Builds, Garage Conversions as well as specialist Brickwork Contractors. Our company is fully insured and our tradesman are all fully qualified. JDL are members of many trade associations including Constructionline, CHAS, Federation of Master Builders and Federation of Small Businesses.
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Latest review:
The project was to construct a 15m2 extension to our rear lounge on the ground floor plus a 4m2 extension to the bathroom on the first floor. This involved foundations, walls and roof tiling in addition to the installation of a 5m long RSJ to support the first floor bedroom. Jamie was selected because of his recent training and apparent enthusiasm. He planned and carried out the work very well. Problems when encountered were discussed and resolved with professionalism and enthusiasm. The resulting work has been completed to a high standard and I am well satisfied with the result. The time taken was as planned, he worked on a daily rate which was to my budget. Jamie' strengths are a good basic knowledge of the building regulations, good communication skills with other workers, suppliers and inspectors and excellent basic brick laying skills with a eye for dimensional regularity and excellent final appearance. I would strongly recommend this young and enthusiastic tradesman for any similar project work involving use of his excellent bricklaying skills.
Regal Contractors Ltd
Rating: 5 out of 5
Extension Builder in Harpenden
Regal Contractors Ltd is a friendly & reliable Bedfordshire based company with over 20 years experience in the trade. We offer a wide range of services such as Carpentry (1st & 2nd fix), Loft Conversions, Extensions, Refurbishments, kitchens & bathrooms, media walls, garden rooms & decking.. We pride ourselves on our finish and have a high attention to detail. Just to add, we are brand new to my builder hence why we do don’t currently have any reviews. Many thanks Ryan
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Latest review:
Completed a ground floor side return and rear extension to our kitchen. Very professional and clear communicator all the way through the job. Tidy worker with a high standard of finish.
Ovi
Rating: 5 out of 5
Extension Builder in Harpenden
Ovi the builder offers a comprehensive service specialising in loft conversions, extensions and refurbishments. We hold over 20 years experience within the construction industry, providing a high standard of work focusing on quality and ensuring a job well done.
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Latest review:
Plastering- 22 Feb 2026
Completed the job on time and as described. No issues and good workmanship. Would recommend
PWF CONSTRUCTION LTD
Rating: 5 out of 5
Extension Builder in Harpenden
FRIENDLY, POLITE AND CONSCIENTIOUS
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Latest review:
PWF construction were never hired to complete my job and the fact that I am now writing a review is an error on my part. Paul Fisher was however very helpful when he provided a quotation for my job and his communication was great.
thegreenorigin ltd
Rating: 5 out of 5
Extension Builder in Harpenden
The Green Origin is a building specialist with a difference, our name reflects our approach to the care of the environment and the value we attach to our clients needs. We apply the highest standards of craftsmanship to deliver our clients first class service and superior finish.
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Latest review:
Thegreenorigin Ltd worked on a full refurb of our office wash rooms in August last year. We had moved into new offices that had been completely renovated with the exception of the bathrooms, which were 20 years out of date! As a busy recruitment specialist in central London, we have an enormous amount of footfall through our offices on a daily basis, including those through our bathrooms, so the quality and resilience of the work was imperative. Thegreenorigin took time to understand our business priorities and worked throughout the night to allow us to maintain use of the bathrooms while they were doing the job. It meant we could still provide facilities to our clients (and staff) whilst they were being refurbished. This was a very important factor for us. In addition to this, they worked around issues which came to light regarding the building we worked in and old pipe work that was still in place, causing sewage issues and completed the project within the timeline we agreed. I would have no hesitation recommending them to other businesses or personal customers.
ATW Construction Services
Rating: 5 out of 5
Extension Builder in Harpenden
I am a local builder with over 20 years' experience. I am a time served Advanced City & Guilds Bricklayer. I am hands on with a small team that work alongside me. I am reliable and offer a professional service. Most of my customers are repeat business. Member of the Federation of Master Builders.
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Latest review:
Gas Work- 4 Dec 2018
A really neat and professional finish. Lots of good advice given. Would recommend to anyone.
S D Wager Brickwork and Building Services
Rating: 5 out of 5
Extension Builder in Harpenden
S.D. Wager are an experienced building contractor trading for over 30 years we always work to a high quality standard and aim to complete jobs on time and on budget. We are a family run business and offer a friendly and personal service to to all our customers. We are also fully insured
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Latest review:
Bricklaying- 27 Mar 2026
Great job from start to finish.
Rosewood Contracting Ltd
Rating: 5 out of 5
Extension Builder in Harpenden
At Rosewood Contracting, we specialise in high end residential and listed buildings. Our team is dedicated to ensuring the successful completion of every project we undertake, with a focus on quality craftsmanship, attention to detail, and timely delivery.
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Latest review:
High-quality work on site, no issues with building control, all signed off straight away with no remedials. Would use again on future projects.
PDK Construction
Rating: 5 out of 5
Extension Builder in Harpenden
PDK Construction. With over 40 years experience, We provide a full building service from start to finish and all work is undertaken by our skilled, reliable and friendly team. We specialise in Large Single and Double Story Extensions which often include the design and installation of kitchens and bathrooms. Also Renovations and refurbishments, both domestic and Commercial
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Latest review:
Extensions- 6 Mar 2023
So glad we found Paul to conduct our house extension. Whilst work is still ongoing I have found Paul to be polite, considerate, and very experienced in the building trade, a big plus point is his costs and reliability. His knowledge is invaluable and has given us lots of ideas to consider during the build. Currently the team of builders conducting works to date have been lovely to be around and brickwork is amazing! Although still some way to go, looking forward to the next few months and the finished job.
A W Building Contractors Ltd
Rating: 5 out of 5
Extension Builder in Harpenden
A W Construction Ltd., provide a full range of building services. Bricklaying Extensions Demolition Patios & Driveways Groundwork Garage conversions Refurbishments Domestic & commercial Free of charge quotations & advice, no extra hidden pricing. No job too big or small! Family run business.
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Latest review:
Garage conversion with extra storage. Completed plumbing, electrics, insulation, plastering, painting. New window supplied & fitted. Recommendation of great floor tilers. All completed on the agreed time schedule and budget.
Guga Home Improvement
Rating: 5 out of 5
Extension Builder in Harpenden
Hello, My name is Ervin.I’m a general builder who has been in the building industry for more than 15 years. offers a comprehensive range of services including:roofing, brickwork, pointing ,painting and decorating,driveway and patios,waterproofing,renovation. Excellent quality job with no regrets or any issues. Looking forward making customers happy and build a business relationship. I’m a honest and professional person, will never disappoint any client Thank you from Ervin.
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Latest review:
Fit 4 new doors, paint the hallway and stairs. Ervin arrived promptly was courteous, clean working, and very willing. I am pleased with the work he did for me and would use him again, and certainly recommend him to others
Antal karoly
Rating: 4.5 out of 5
Extension Builder in Harpenden
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.
Wilson Builders
No reviews yet
Extension Builder in Harpenden
With over 10 years of hands-on experience in the building trade, we specialise in high-quality domestic extensions that transform homes and improve the way our clients live. Whether it’s creating open-plan living spaces, adding new bedrooms, or reimagining kitchens, we bring expert craftsmanship and a keen eye for detail to every project. We pride ourselves on being approachable, reliable, and honest — from the first consultation to the final handover. No two jobs are the same, and we genuinely love a new challenge. Whether you’re working with tight spaces, complex layouts, or bold design ideas, we’re here to bring your vision to life. Our team understands how important your home is, and we treat every project with the care and respect it deserves. If you’re planning an extension and want a team that combines experience, passion, and problem-solving skills — we’d love to hear from you.
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TPS Groundwork & constrution
Rating: 5 out of 5
Extension Builder in Harpenden
extensions, driveways,paving,groundwork
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Latest review:
Bricklaying- 6 Nov 2020
Tony gave me a competitive quote, not the cheapest but everything about him was professional and gave me confidence. His team arrived on time the day of the build and were helpful and pleasant. They worked all day and cleaned up and covered their work until they arrived on time the next morning. They worked hard all day. After the wall and piers were build all the brickwork and joints were left clean and crisp. I am very happy with the wall. I have renovated many properties over the years and the standard of this job was excellent. I highly recommend them.
Evanescence builders
Rating: 5 out of 5
Extension Builder in Harpenden
Evanescence Builders is a proud, family-run business with over 10+ years experience in the trade. Dedicated to delivering exceptional craftsmanship and a personal touch to every project. We treat every job as if it were our own, striving for perfection from start to finish, providing guarantees on all work completed and fully insured. So give us a call to get your free quote today!
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Latest review:
Bradley did an excellent job painting 4 exterior walls at the back of our house. At the start he provided a simple clear quote referencing the different parts of the process. He turned up on time and was great throughout. I’d happily recommend him!
Michael John Interiors
Rating: 5 out of 5
Extension Builder in Harpenden
Hi I'm a general builder, started my working life on kitchen & interior design then also Installations, which quickly lead to building works. Taking down walls to building large extensions/loft conversions & out side works We take on any size work & can offer lots of advice & design help, having 35 years experience From kitchen installations & all types of Interior work To extensions/outside works & loft conversions.
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Latest review:
Extensions- 15 Apr 2019
Submitted quote on time and has responded to all questions and been very helpful.

3.3

Top rated Extension Builders

Our Extension Builders in Harpenden, are rated 3.3 out of 5 based on 10 reviews from customers like you.

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What types of services are offered by local extension builders in Harpenden?

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 Harpenden 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 Harpenden who are available and interested can respond to your post.

Browse profiles, read customer reviews and get quotes from your chosen Harpenden extension builders, all before you decide who to hire.

What are the hourly rates of extension builders in Harpenden?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Harpenden 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 Harpenden extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Harpenden home extension project is likely to cost.

Find extension builders in Harpenden with MyBuilder

Hiring the right extension builder in Harpenden 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 Harpenden extension builders. Once your job is live, we’ll share it with home extension builders in Harpenden who can express their interest.

Step 2: Compare different extension builders in Harpenden

When you start receiving interest, review profiles of local Harpenden extension builders, check their previous work, and read real customer reviews. Ask about timelines, materials, and request detailed quotes.

Step 3: Hire Harpenden extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Harpenden, 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.

Harpenden extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Harpenden extension builder before hiring?

Before hiring an extension builder in Harpenden or extension building company in Harpenden, 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 Harpenden?

An extension builder in Harpenden 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 Harpenden 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 Harpenden?

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 Harpenden 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 Harpenden 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 Harpenden

Can an extension builder in Harpenden help with planning permission?

Yes, many extension builders in Harpenden 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 Harpenden handle everything from design to construction?

Many Harpenden 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 Harpenden help with materials and finishes?

Yes, most extension builders in Harpenden 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.