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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Guarded Properties
Rating: 4.7 out of 5
Extension Builder in Harpenden
All works covered by £1m Public Liability All Building Works New Builds Extensions Refurbishments Outbuildings Roofing Bricklaying Electrics Carpentry GRP Roofing Asbestos Roofs Flooring Fascias Guttering Plastering Tiling Painting Decorating Ground Works Patios & Paving Fencing Carpeting Liaising with Building Control & Planning Your one stop construction shop!! High quality works Competitively priced Will beat any formal quotation on like for like basis!
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Latest review:
Extensions- 4 Jun 2022
Danny designed and built us a garden room to fit a challenging space at the bottom of our garden. His communication from start to finish was excellent, and he did an brilliant job on the room, inside and out. I would recommend Danny for any job, big or small.
BSD Design & Build LTD
No reviews yet
Extension Builder in Harpenden
🏗️ Build with Confidence – Build with Us! 🏡 B.S.D Design & Build is a proud member of FMB. Not every builder is a Master Builder! In an unlicensed industry, choosing a Federation of Master Builders member gives you peace of mind, knowing we meet strict entry criteria and undergo continuous monitoring. ✅ Expert Craftsmanship ✅ On-Time & On-Budget ✅ Built to Last Trust the professionals. Contact B.S.D Design & Build today! 📞🔨
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Bawabuilder
Rating: 5 out of 5
Extension Builder in Harpenden
We can extend
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Latest review:
Fencing- 13 Mar 2026
We hired Bawa to install new fencing, and he did a fantastic job from start to finish. You can immediately tell he’s an all-rounder who understands construction very well. The work was carried out efficiently and to a high standard. Bawa has a great attitude, is very hard-working, and clearly takes pride in what he does. Communication was easy throughout, and the whole process felt smooth and professional. It was a real pleasure having Bawa work for us, and I wouldn’t hesitate to recommend him.
LEBELLE HERITAGE & RESTORATION LTD
Rating: 5 out of 5
Extension Builder in Harpenden
Lebelle Heritage & Restoration Lebelle Heritage & Restoration is a professional building and construction company specialising in renovations, refurbishments, and heritage restoration. We take on all types of projects, from full property renovations and structural upgrades to detailed interior finishes and the careful restoration of period features. Our team is skilled in both traditional craftsmanship and modern construction methods, allowing us to deliver work that is reliable, high-quality, and built to last. Whether we’re restoring the character of an older property or breathing new life into a modern home, we focus on precision, honesty, and clear communication throughout every stage of the job. We pride ourselves on delivering clean, efficient, and well-executed work that meets the needs of our clients and respects the integrity of each building. At Lebelle Heritage & Restoration, we build, renovate, refurbish, and restore with a commitment to quality and long-term durability.
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Latest review:
After a previous contractor took our money and left our loft extension unfinished, we were devastated and worried about how we would ever get our home back to normal. Then Lewis from Lebelle stepped in and completely turned things around. Lewis was patient, understanding, and incredibly professional. He worked quickly, kept costs under control, and finished the loft extension to a standard we’re so happy with. The stress he took off our shoulders was unbelievable. We honestly can’t thank Lewis enough. If you’re looking for someone trustworthy, skilled, and genuinely caring, Lebelle is the company to call.
JCH Home improvements & landscaping
Rating: 5 out of 5
Extension Builder in Harpenden
Local builder with 20 years experience in the construction industry. From extensions to bathrooms, windows, doors, patios, kitchens, fully landscaped gardens. Please get in contact for your free no obligation quote
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Latest review:
Decking- 14 Jun 2022
James Hynes of JCH Home Improvements have just refurbished our decking area. We thought it was a straight forward job, just to renew the decking and a tidy up BUT the original wood was so rotted the whole area had to be renewed. Joists, upright timbers etc We are thrilled with what James has done, so much more work than anticipated but the end result is fantastic. Would thoroughly recommend JCH Home Improvements and we will be using the again.
RA Designs and Build Ltd
Rating: 5 out of 5
Extension Builder in Harpenden
We are a dynamic construction firm specialising in innovative design and high-quality building solutions for both residential and commercial projects. With a commitment to excellence and attention to detail, our team of experienced architects, engineers, and skilled tradespeople collaborates closely with clients to bring their visions to life. We prioritise sustainable practices and utilise cutting-edge technology to enhance efficiency and ensure the durability of our structures. From initial design concepts to final construction, we are dedicated to delivering projects that not only meet but exceed client expectations, creating lasting value and aesthetic appeal. Our customers consistently recommend us for our commitment to quality, attention to detail, and exceptional customer service. They appreciate our ability to turn their visions into reality while staying on schedule and within budget. Positive testimonials highlight our professionalism, seamless communication, and the collaborative approach we take throughout each project. Clients feel confident entrusting us with their building needs, knowing that we prioritise their satisfaction and work tirelessly to ensure memorable and successful outcomes.
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Latest review:
Excellent quality of work which has not caused any problems for many years. Efficient work style whilst keeping up a high standard of work.
RDS Building Services Ltd
Rating: 4.8 out of 5
Extension Builder in Harpenden
We are a team of dedicated master builders based in Milton Keynes who specialise in high quality extensions & rapid construction of shell only builds. 25 yrs experience in residential builds, from single room additions to bespoke new builds. Extensive work history with trusted teams ready to work with outstanding attention to detail & professionalism. Members of FMB, and CHAS & Safe Accredited. Design service, project management & full construction offered as part of our service.
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Latest review:
Extensions- 27 Jul 2023
I would be happy to use RDS buiding services again. They turned up every day worked efficiently and kept the mess created by the construction out of the way of the neighbours. The budget we agreed was followed and the stage payments schedule worked throighout the build. I am very happy with the quality of the work and more importantly the attitude of the builders who worked with us when inevitable snags came along. We invited RDS to do some additional work (landscaping in the garden) which did not detract from the main job. Thanks RDS for a job well done.
M&B Civils
No reviews yet
Extension Builder in Harpenden
At M&B Civils we provide all aspects of groundworking and landscaping at a high level of quality. We focus to keep the costumer happy with our job and price.
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VNG Interiors LTD
No reviews yet
Extension Builder in Harpenden
🏠 VNG Interiors LTD - Transforming Visions to Reality 🏠 We specialise in residential & commercial construction, renovations, extensions, & structural repairs. Our commitment to quality, transparent communication, & competitive pricing sets us apart. Your dream project starts here!
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Niall paine
No reviews yet
Extension Builder in Harpenden
I have been in the bricklaying trade for 17 years, fully qualified nvq 2. Work to a high standard, have worked on all types of bricklaying jobs from sites with multiple houses to small garden walls and repointing. Reliable and hardworking.
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MP Fast Brickwork Contractors Ltd
No reviews yet
Extension Builder in Harpenden
Hi, I’m an experienced bricklayer with over 10 years in the trade. I specialise in all types of brick and block work — from garden walls and extensions to large-scale construction projects. For the last 4–5 years, I’ve also been working as a foreman/supervisor, managing teams and ensuring top quality on every job. My team and I work fast, professionally and always deliver high-quality results with great attention to detail. I take real pride in my work, and many of my customers are happy to recommend me. You can also see our projects on Instagram: @m.p.fastbricklayers
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New build, refurbishment & maintenance
No reviews yet
Extension Builder in Harpenden
Hello, We are a reliable construction company specialising in commercial & high end residential fit - outs & refurbishments. Our team is made out of skilled tradesman, reliable, experienced & knowledgeable. You'll have one reliable point of contact throughout the works and all the support needed. We take great pride in our work ethic and the quality of our finishes. New to "my builder", as opened an account to fill gaps between our normal projects but can give many references on request.
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RDB Contractors Ltd
No reviews yet
Extension Builder in Harpenden
we use to do any dry-lining partitions, metsec works, loft conversions, extensions, carpentry works, tiling, suspended ceilings. We have about 10 years experience. we also do roofing works in fibre glass.
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J.Miles Building
No reviews yet
Extension Builder in Harpenden
General builder. Level 3 qualified bricklayer. .Extensions .Chimney refurbishments .Guttering .Fascias .Soffits .Driveways .Brick wall repairs .Knock throughs .Roofing
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Arisen Ltd
No reviews yet
Extension Builder in Harpenden
Hi, I'm Edwart, Managing Director at Arisen Construction Ltd. We specialise in interior refurbishments, kitchen fitting, flooring, and general renovations. With a reliable team and a focus on detail, we aim to deliver quality workmanship and customer satisfaction in every project. Based in London and fully insured, we're here to bring your vision to life — efficiently, safely, and to a high standard.
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Urban Doors&window Glazing Ltd
Rating: 5 out of 5
Extension Builder in Harpenden
Welcome to Urbandoor & Window Glazing Ltd! We are your local specialists in doors, windows, and glazing solutions, providing high-quality installations across the UK. Whether it’s bi-fold doors, UPVC or aluminium windows, skylights, or roof lanterns, we combine premium products with expert craftsmanship. Our team is committed to reliable service, precise measurements, and flawless installations. Every project is carried out to British standards, ensuring safety, energy efficiency, and durability. Call us today for a free quotation and let us brighten your home with quality doors and windows!”
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Latest review:
Veeno is a great guy,i called him for an emergency job and he drove down almost immediately to get the job done with a very fair quote…i will always recommend him.

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.