Extension Builders in Harpenden

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.6 (12 reviews)

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Some of our top rated extension builders in Harpenden

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imsbuilders
Rating: 5 out of 5
Extension Builder in Harpenden
I have over 40 years of experience in the industry. I am a fully qualified bricklayer and also a fully qualified carpenter. I have had the pleasure of constructing many extensions new builds and home renovations for my clients, ensuring the whole project runs smoothly and safely
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Latest review:
Carpentry- 28 Apr 2024
Great experience. Bill was very nice, knowledgable and quickly fixed an issue with our unsupported floorboards, for excellent value too. Would definitely recommend!
crimson kite construction
No reviews yet
Extension Builder in Harpenden
Fully experienced, impeccable attention to detail. Able provide a design service or complete a project to architect specifications.
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JR Brickwork
Rating: 5 out of 5
Extension Builder in Harpenden
I take on work covering all aspects of bricklaying, repointing, patio laying and any general maintenance work.
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Latest review:
Jack was punctual and professional and finished the work to a high standard. I will happily be recommending him to friends and family.
m j m builders
Rating: 5 out of 5
Extension Builder in Harpenden
We do most types of building work also resin drives all types of landscaping. I have worked in construction since leaving school, I have been working foreman for firms also contracts manager for a firm specialising in care homes and I am now 53 years old.
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Latest review:
Extensions- 18 Jan 2020
In October 2018, I asked Michael to do a rear part single storey part double storey extension. Michael completed the job mid January 2019, which also included relaying the patio, fitting a pre-bought kitchen and building a new porch. Michael, Bill (the electrician) and the rest of the team have done an excellent job transforming our home into something so much more than it was. I was very impressed with his work ethic and his knowledge, and appreciated the advice he gave us which showed his experience. The electrician also was able to successfully rewire our home to bring up to the required standards and was willing to work on weekends to get the job done (that was partly our fault, sorry!). Any issues and disputes, of which there were very few mind you, were dealt with promptly and properly. All in all, if you're looking for a trustworthy, high quality builder in the Hitchin/Letchworth area then do get in touch with Michael. Thanks again for the excellent work! Also, if you'd like to see his completed work, please drop me a message and you're welcome to come and have a look at the work that was done.
Eddy Brickwork
Rating: 5 out of 5
Extension Builder in Harpenden
With 10 years of experience in bricklaying, I provide top-quality craftsmanship for both residential and commercial projects. From building sturdy foundations to creating stunning brick facades, my work combines precision and durability. I take pride in delivering results that meet your exact specifications and exceed your expectations. Whether you need new construction, repairs, or custom brickwork, I'm dedicated to providing reliable and efficient service. Let's bring your vision to life with expert bricklaying skills!
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Latest review:
Bricklaying- 20 Jun 2026
Eddy was very professional. The work was completed on time and on budget. He did a fabulous job and left everything clean and tidy. He was respectful of my property and if I need work done in future I will be happy to use Eddy again.
B & M Home Improvement
Rating: 5 out of 5
Extension Builder in Harpenden
We are a local and reliable Plumbing, gas safe and Home Improvement Company in London and surrounding areas.I gained my experience working in the Plumbing and gas department. No matter whether you require help with plumbing, power flushing, boiler installation, bathroom, kitchen, extention, flooring we take on all building work. We provide a full interior decorating service for domestic and commercial.
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Latest review:
Extensions- 10 Apr 2014
Max and Bob completed the extension on time and within budget. There were no hidden extras and despite Bob being on holiday for two weeks, Max worked hard and lon. The extension is 6m x 5m. There were issues with Building Control which Max sorted out and did everything to meet their requirements. The extension is built to a high standard, kitchen cabinets fitted well, tiling very good and we are pleased with the quality of their work. We are using B&M again as we are confident that although they are not tghe cheapest, the quality of their work is of a high standard. Besides, it is always a pleasure to deal with Max who is a gentleman, patient and listens to what is required.
Redriver loft converters ltd
No reviews yet
Extension Builder in Harpenden
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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BARNETTS BESPOKE
Rating: 5 out of 5
Extension Builder in Harpenden
At Barnetts-bespoke we specialise in high quality custom carpentry and building solutions tailored to your unique needs, proudly serving all areas of Hertfordshire and London we offer high end craftsmanship for a wide range of projects including bespoke wardrobes, kitchens, bespoke storage solutions, and complete renovations Our complete list of services are listed below *kitchens *bathrooms *extensions * bespoke wardrobes/cabinetry *roofing *flooring * summerhouses * Returbishments * new build
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Latest review:
Carpentry- 11 May 2020
Charlie was absolutely brilliant, fist class tradesmen with extremely high standards Will definitely use and recomend to others
Slateriver Group Limited
New on MyBuilder
Extension Builder in Harpenden
Our highly-experienced team cover everything from light to heavy refurbishments, as well as new builds. We’re experts at transforming spaces, with minimal disruption. So, whether you need a brand new development or alterations to an existing space, we can navigate all the complexities on your behalf so that you can enjoy watching your vision emerge.
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Lee Construction Builders LTD
Rating: 5 out of 5
Extension Builder in Harpenden
Lee Construction Builders LTD are your local Builders in Stevenage. We offer free quotations and can build your project for a fixed price. All our team are fully qualified and experienced tradesmen that have seen and dealt with every building challenge possible. We have a track record of happy satisfied customers as we provide a friendly, professional service, and are always respectful of our customers, understanding that our workplace is your home.
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Latest review:
Roofing (Pitched)- 17 Apr 2016
Fantastic job; quick reply; thorough professional job. Lee really likes doing the job right; certainly not a cowboy. He really took his time in assessing the problem. Very neat job from the inside and out. Highly recommended.
Byott and Attfield construction
No reviews yet
Extension Builder in Harpenden
We are a fully qualified experienced team of all trades, carpentry, bricklaying. We offer the full building package from hanging doors to new builds.
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Made Innovate Constuction & Reform
Rating: 5 out of 5
Extension Builder in Harpenden
We are what we would like to call a complete construction company. Due to many years of success and co-projects, we partnered with a Structural Engineer to provide a hassle-free, top-notch service and projects. We have over 30 years of experience with a team of experts who specialize in construction management, design, and build services.
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Latest review:
Andre undertook a seemingly impossible task within my own home. They transformed my down stairs storage in a w.c, the gas lines were repositioned, he and his tem also built an outdoor storage area. Their honesty, dedication, and commitment to finding the best solutions both in terms of cost and quality were truly exceptional, they transparently outlined the challenges and worked tirelessly to deliver results that went beyond expectations. I totally recommend Andre and his team if you are looking for a highstandard professioanal that really cares about people and getting the job done!
Solid building aspect Ltd
No reviews yet
Extension Builder in Harpenden
Solid Building Aspect Ltd is a specialist construction company delivering high-quality residential and commercial projects across London and Hertfordshire. With over 20 years of industry experience, we focus on extensions, structural alterations, renovations, and modern steel frame (SFS) systems — offering a more precise, efficient, and reliable way to build. We also design and build bespoke garden rooms and install premium aluminium and composite decking systems, creating functional, modern outdoor spaces tailored to each client’s needs. Our approach combines strong project management, attention to detail, and clear communication from start to finish. Whether transforming a home, adding flexible living space, or delivering complex structural works, we focus on results that add real value and stand the test of time.
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ABL Building & plumbing solutions
Rating: 5 out of 5
Extension Builder in Harpenden
We are a family run business, take pride in our work we carry out. We cover all aspects of building works from hanging a door to a complete new build house.
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Latest review:
Plumbing- 28 Jun 2023
Alan was a total professional, clean and tidy, fabulous job, will use him again and recommend him to everyone I know. Top professional.
GSrenovation
Rating: 4.9 out of 5
Extension Builder in Harpenden
We have 25 years of property renovation .During the last 15 years GSrenovation has specialised in fitting and renovating bathrooms, kitchens and extensions . We believe that our success stems from our exacting professionalism and true enjoyment of our work. We take as long as is needed to help customers from design through to completion. For peace of mind GSrenovation also provides 5 years guarantee with each installation. Sensible prices. Free quotation and advice.
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Latest review:
Kitchen Fitting- 10 Jul 2024
George has done an excellent job. He is highly recommended, and his prices are reasonable.
Choice Build
Rating: 5 out of 5
Extension Builder in Harpenden
We are a small team specialising in plastering, carpentry and building. We can carry out full refurbishments, removal of load bearing walls, extensions, garden rooms, garage conversions and much more. With over 15 years each in our trades we strive to complete every job to the highest finish and feel combing plastering and carpentry we have the skill sets to do this. Electric and plumbing works are carried out by qualified tradesmen
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Latest review:
Restoration & Refurbishment- 14 Aug 2020
Excellent work ethic and attention to details. All-round nice guys to have around, finished the job on time and left in a tidy manner.

3.6

Top rated Extension Builders

Our Extension Builders in Harpenden, are rated 3.6 out of 5 based on 12 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.