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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Aman constructions Ltd
Rating: 5 out of 5
Extension Builder in Harpenden
Hi My name is Aman we undertake all kind of construction work including refurbishment, extensions, loft conversion and new build
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Latest review:
Extensions- 14 Feb 2025
Kamal, was fantastic start to finish. Fair pricing. They were quick and but no corners where cut. Superb performance and communication. I will be using Aman Construction for all my building needs going forward and recommend you do too. I would give them 10 out of 10
Roozbeh
No reviews yet
Extension Builder in Harpenden
3D-Design Build and Maintenance
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Buildwright contractors ltd
No reviews yet
Extension Builder in Harpenden
Over 20 years of experience in the trade. Alongside electrical work, I also specialise in property renovations and conversions, delivering high-quality workmanship across a wide range of projects. I take pride in working to a high standard, ensuring every job is completed safely, efficiently, and to the client’s satisfaction.
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R KELLS LTD
No reviews yet
Extension Builder in Harpenden
Hello, and welcome! I’m Rkan the owner and lead builder of R KELLS LTD . With years of experience and a commitment to exceptional quality, I’m proud to be known as one of the best builders in London. Whether you’re looking to renovate, extend, or start a completely new project, I bring both expertise and passion to every job. I work closely with my clients to ensure that their vision becomes a reality, on time, on budget, and with the highest standards of craftsmanship. My focus is always on providing a hassle-free experience and delivering outstanding results. Let’s create something amazing together!
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Braham Glazing Ltd
Rating: 5 out of 5
Extension Builder in Harpenden
Finance Available : We are "Braham Glazing Limited" a reliable family company in London. We provide our customers with high class and excellent quality designs and build services whether it's windows, doors, conservatory or a porch throughout the UK. We respect the individual expectations of each customer and provide tailor-made solutions with bespoke products designed specifically for each customer. We work with passion and dedication towards every job big or small.
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Latest review:
Windows & Doors (uPVC & Metal)- 3 Apr 2025
Garry and team were very knowledgeable about how the windows should be installed. They managed to retain the Victorian features of the existing windows and were perfectionist when it came to finishing each window. I am very happy with my windows and would highly recommend them.
Darktolight
Rating: 4.5 out of 5
Extension Builder in Harpenden
WELCOME to DARK 2 LIGHT CONSTRUCTION LTD. We are team of builders and electricians and all the trades . Our website is available to get more information ! Our team is made up of qualified, trusted and experienced workers . No job is too small or too big, we offer a big range of services . Call now to get a free quote !
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Latest review:
Extensions- 14 Jun 2023
⭐️⭐️⭐️⭐️Excellent Builders.👍👍⭐️⭐️⭐️ I used different types of builders for the past 10yrs for various type of job. But I would tell DARKTOLIGHT are THE BEST of all. They are skilful, honest, punctual, friendly, economical, and very professional. They always consider your financial situation and help your building/repair needs accordingly. They complete the job with the fullest satisfaction on time. I have already booked for more of my other jobs. Highly recommend.10/10.
SSB Building Services Ltd
Rating: 5 out of 5
Extension Builder in Harpenden
Hi. My name is Sylvester and I would like to introduce to you SSB Building Services Ltd. We have over 15 years experience specialising in all aspects of general building services including extensions, loft conversions, kitchen and bathroom fittings, carpentry, restoration and refurbishment, decorating and many more.
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Latest review:
Kitchen Fitting- 11 Nov 2019
A fantastic job. I am very pleased with the new worktop and my kitchen was left clean and tidy. I would highly recommend this builder. Lindsey (Northampton).
Lan Lin
New on MyBuilder
Extension Builder in Harpenden
We are a team of qualified civil engineers with more than 10 years of experience in building construction and property improvement services. Our work includes house builds, extensions, loft conversions, shed , greenhouse construction, furniture installation, repairs, and a wide range of handyman services. We are reliable, hardworking, and committed to delivering quality results for every project. Customer satisfaction, professionalism, and punctuality are always our priorities.
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fedora and sons
Rating: 4.4 out of 5
Extension Builder in Harpenden
I have started working for myself in Europe for 10 years, came over to England with my family and have been working here for 11 years getting business from word of mouth. In my business I manage lots of sub contractors covering a wide range of trades which I have experience in too.
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Latest review:
Painting & Decorating- 24 Feb 2020
Quite literally the worst tradesman I have ever worked within 25 years as a property developer! He came and quoted to paint my house (a good price I must say), little did I know that this meant he would spray everything that he can see, not prepare the surfaces by sanding them down or protects things. This included door handles, hinges, radiators, alarms sensors, tiles and my own furniture and cooking utensils. First time I confronted him about this he said that we would clean everything, and we agreed to carry own. However, it became apparent that we was doing the same as previously discussed. have paid hi 66% of what was agreed, I quickly realised that the damaged he has caused was going to cost me far more and I told him to leave. The next day he turned up at my house with his wife demanding the balance which I refused to give him, they were both shouting outside my house, threatening to call the police. I eventually agreed to pay the 50% of what was left, just so that they would leave. However, even once he had confirmed writing his acceptance of this, he walks over to me and threatened me one final time, saying that he will take me to court etc, there is god and he will see to me! I advise to stay away from this person, better to pay a little more and work with professionals who don't agree with one thing and do another. He paints using a spray, which means you can not touch anything up and he quite literally paints everything he sees!!
Good Choice Builders LTD
Rating: 5 out of 5
Extension Builder in Harpenden
We are the building company that specialized in Loft Conversions, Extensions and Refurbishments. By this moment we worked as a subcontractors, now we have all neccessary and feel free to participate to the tenders, prepare the informative and detailed contracts and estimations, management.
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Latest review:
Extensions- 8 Jul 2019
A very efficient builder who did the plans which where passed first time when we needed help he found someone to help very clean and tidy and on time
mbond
No reviews yet
Extension Builder in Harpenden
Our team undertake building projects for last 15 years in London and surrounding areas - we doing lots of HI-end bathrooms and kitchens ,extensions ,loft conversion and general refurbishment works. We can provide references from our clients plus its always possible to visit one of our current projects or in some cases past projects as well.
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Boris
No reviews yet
Extension Builder in Harpenden
We do all jobs necessary, from full refurbs to plumbing works to building your house ground up and gardening needs too.We have a professional team of skilled workers in this domain and always deliver. We finish all jobs on time and we pride ourselves on the quality that we provide.
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Powerbiz ltd
Rating: 4.2 out of 5
Extension Builder in Harpenden
Hi, We are a LOFT conversion and EXTENSION specialists to look after the construction side of the building works. Over 20 yrs of experience and accumulated variety of different skills. We take pride in our teamwork and always keep costumers interest on high priority . On qualification side I am a GAS SAFE registered and undertake works like New boilers , central heating and underfloor heating, also a REFCOM registered air-conditioning installer Many thanks and hope to hear from you soon.
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Latest review:
Extremely professional and great attention to detail. Very approachable and committed. The job carried out was of very high quality and neat. Complete transformation of my Living Room.
Angle Construction
Rating: 4.7 out of 5
Extension Builder in Harpenden
We have been in the construction business for over 15 years doing all sorts of works, from minor works to full home constructions. No job to small no job to big. We work in and around London
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Latest review:
Windows & Doors (uPVC & Metal)- 28 Jan 2026
Very unhappy with how things went with Angle Construction overall. Poor comms during the transaction was the first red flag - no communication for 2 days the moment money was sent, however afterwards received an apologetic call - parts ordered and arrived in due course. Andrei turned up, and got to work on removing the old gate, but then started shaving down the post without saying anything -we were told after that the posts were not level. Eventually he said the door would need to be cut, which we agreed to. The door and posts were both cut to fit, but massive gap left at the bottom, and only half of the door fittings and no handles were installed! In addition, where the door was cut and the wood shaved made, a lot of mess was left all over the garden furniture and patio floor. Shocked at the lack of care and professionalism. He was clearly agitated and in a rush to leave. We have a working back door, but it looks like a real botched job. Not happy, and I would not recommend.
Downtown Builders
No reviews yet
Extension Builder in Harpenden
Welcome to Downtown Builders, a small family-run business between 4 brothers who was taught by there grandfather with over 15 years of experience in the construction industry. Our team specializes in brickwork, and extension building, providing high-quality services to our clients across the region. We take pride in delivering exceptional craftsmanship and personalized service to every project we undertake. Whether you are looking to build a new extension to your home or in need of repointing a new garden wall a pizza oven bbq for the summer anything you need our team has the expertise and dedication to meet your needs. With a focus on attention to detail and customer satisfaction, we strive to exceed our clients' expectations on every job. From concept to completion, you can trust Downtown Builders to bring your vision to life. Contact us today to learn more about our services and how we can help you with your construction needs. Thank you for considering Downtown Builders for your next project.
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Landscaping
No reviews yet
Extension Builder in Harpenden
Daniel Landscaping
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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.

Quality screening

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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.