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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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.
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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Bespoke Made Limited
No reviews yet
Extension Builder in Harpenden
With 20 years of experience in bespoke made windows and doors, our company is dedicated to delivering top quality products tailored to your unique needs. We pride ourselves on being professional and friendly, ensuring every project is completed on time without compromising craftsmanship. Trust us for exceptional service and custom solutions that enhance your space. Fully insured and Fensa registered.
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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.
Nick's Authentic Carpentry and Building
Rating: 5 out of 5
Extension Builder in Harpenden
We're a new company but have the experience and knowledge of any other company.We're professional, organised, and give our customers what they expect and deserve. Being proud workers and undertaking everything thats thrown at us, Our focus is the job we're on!
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Latest review:
Carpentry- 31 Aug 2011
Highly recommended and friendly carpenter. The job was done within 24 hours of posting. He gave me a time and even called to say he was on his way. Price was very reasonable indeed. Job was done to my total satisfaction with 100% professionalism. I am certainly going to have Nick do any other jobs that arise. He clearly has a vast knowledge of a whole range of trades and skills apart from carpentry. It is so nice to have found such an able tradesman who can be trusted to do a great job.
F S Building Services
Rating: 5 out of 5
Extension Builder in Harpenden
Hi I am the owner of a small building company. We do all types of building work especially loft conversions & extensions, also fitted bathrooms & kitchens. External work Inc roofing & external decorating. GRP & EPDM rubber roofing. I am personally a carpenter by trade with over 35 years of experience.
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Latest review:
Bathroom Fitting- 2 Sep 2020
Really pleased with our new bathroom, total redesign and replacement including tiling. Fred could not have been more helpful offering advice on the design and options to get everything in we wanted. He and the team were punctual, clean and tidy (well as best you can under the circumstances!) friendly and helpful. Definitely recommend.
JHF Construction Limited
Rating: 5 out of 5
Extension Builder in Harpenden
JHF Construction Ltd have been established as a limited and VAT registered company since March 2018. Located on the outskirts of Hitchin, our brand-new Studio is an example of our work and welcomes visits. We provide a reliable, professional service with innovative concepts and pride ourselves on the quality of our work. We offer everything from design through to completion and work hand-in-hand with our clients to ensure expectations are met and exceeded. Always striving to go the extra mile.
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Latest review:
Kitchen Fitting- 27 Feb 2019
Jack and the team did a great job on our new kitchen including new electrics, tiles and underfloor heating and we’re truly delighted with the end result. Jack was always available to discuss the project and answer any questions or concerns I had and was able to quickly overcome issues we experienced relating to the kitchen units and a design error. He was always professional and gave us useful tips and input into the overall kitchen design and helped us source very nice materials. As with many small businesses, Jack and the team were juggling other jobs along side ours which meant that after some unexpected additional work on our floor, they were unable to complete the job within the original timeframe plus 2 days contingency. As a family with young children we found this really difficult so I would urge you to project manage closely. It was all totally worth it in the end though and overall I would recommend Jack and the team.
SFL Construction Ltd
Rating: 5 out of 5
Extension Builder in Harpenden
SFL Construction is a Hertfordshire-based construction company, building a wide range of structures and completing all construction phases from the foundation to the roof and everything in between. Our team brings years of experience and expertise to every project we undertake.
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Latest review:
Ryann and his team first completed a multiple room ground floor extension for us, including the installation of a new kitchen and bathroom. We were so pleased with the work that we asked him to build an outdoor garden room from scratch and completely refurbish our other bathrooms. We have always found Ryann to be friendly, punctual, knowledgeable and honest and I am more than happy to give my recommendation.
Marian Disca
Rating: 5 out of 5
Extension Builder in Harpenden
Hi We undertake a variety of work,loft extension,bathrooms,kitchens,roofs,floors.etc With a experience of 15years there’s not much we haven’t done. Reference available!
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Latest review:
Joinery & Cabinet Making- 19 Apr 2019
Marian is i would say a master craftsman . He did an excellent job with the 2 alcove bookshelves. The alcoves were big and i wanted most of the period features and he made it exactly as per my specifications he also helped mount my tv on one of the units and looks very clean and he also helped conceal all wiring for my electric fireplace. I will definitely use his services again.
What 4 Building Solutions LTD
Rating: 4 out of 5
Extension Builder in Harpenden
Here at What 4 Building Solutions LTD, We cover all aspects of the of the building process. From helping with design using our amazing architects. Getting your ideas through planning and building regs, then making your dreams come true. We cover Herts, London, Essex & Cambridgeshire. Taking on any size project from new builds to a refurb or even just a new kitchen we can help. We offer man and machine hire and licensed waste removel. We have all the trades on hand ready to go so we have no delays on our projects. We have the SOLUTION for your project... We are pround Members of the Federation of Master Builders and TrustMark the only Government Endorsed for Quality work.
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Latest review:
Extensions- 21 Mar 2026
I am a Chinese Lady honourably established at Hollyview Close, London NW4 3SZ, of at least sixty years of age, and distinguished by the wearing of spectacles, which bespeak both careful attention and the wisdom accrued through decades of devoted service. I am entrusted with the disciplined and esteemed practice of electrical repair and maintenance, a vocation carried out with the utmost reverence for order, propriety, and the impeccable standards befitting households of the highest esteem. Upon my arrival, I bring forth with equal dignity both the meticulous execution of all electrical works and the ceremonial offering of fine chewing gum, bubble gum, and freshly selected lemons, each item presented with deliberate attention to freshness, quality, and presentation, in the grand tradition of British hospitality and courtly decorum. The chewing gum is carefully curated to encourage measured mastication, fostering calm, poise, and contemplative steadiness; the bubble gum is reserved f
Warwick Ainsworth Design & Build Ltd
No reviews yet
Extension Builder in Harpenden
Specialising in quality extensions and refurbishments. Attention to detail assured. Extensive experience of eco-solutions. Approachable and honest appraisals of projects.
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GA Living Spaces Ltd
Rating: 5 out of 5
Extension Builder in Harpenden
George Alexander Living Spaces is a family-run business specialising creating and re-novating "Living Spaces" within residential properties. As a company, with over 30 years experience, we specialise in all aspects of building works; from constructing a timber frame house from scratch; extensions; loft & garage conversions; refurbishments; designing and manufacturing your new kitchen; bathroom or stone worktops - through to boarding and plastering internal walls!
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Latest review:
Kitchen Fitting- 11 Dec 2018
Our kitchen looks very nice and bright and everything we required has been achieved, at a competitive price. The team were very polite,considerate and hardworking. There have been a couple of hold ups along the way, but we are pleased with the finished product.
Poles Apart Construction
No reviews yet
Extension Builder in Harpenden
Hi all My names is Gracjan Im from Poland . I have 17 years experience in carpentry Joinery 1 and 2 fix .This is my passion so I can do anything made of wood. Thank you
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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.
KalociconstructionLtd
New on MyBuilder
Extension Builder in Harpenden
Top cuality and cline work
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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.