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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Flynn Construction ltd
Rating: 5 out of 5
Extension Builder in Harpenden
We are a medium sized Limited Company based in Watford . We specialise in all area's of building - New builds, Refurbishments, Extensions and Paving all welcome. We have a vastly experienced team to cater for all your building needs.
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Latest review:
Extensions- 12 Jun 2020
Gavin project managed the rear story extension on our house from start to finish and was professional and friendly throughout. He was always on hand to offer help and support and we would definitely recommend his services.
Switch Electric Services Limited
Rating: 4.9 out of 5
Extension Builder in Harpenden
A fully qualified electrician is a highly skilled professional equipped with comprehensive knowledge and expertise in all aspects of electrical work. With rigorous training and practical experience, they excel in designing, installing, and maintaining electrical systems with utmost precision and safety. From residential wiring to industrial installations, fully qualified electricians play a crucial role in powering the modern world, enabling progress, and illuminating our lives.
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Latest review:
Electrical- 9 May 2026
He was good on price for the first inspection and attended as agreed. However, I was less happy with the remedial quote. Several items quoted did not appear to be needed, while some items that did need attention were not included. Overall, fine for the inspection, but I would have preferred a more accurate and practical quote for the follow-up work.
Ian Warren Brickwork
Rating: 5 out of 5
Extension Builder in Harpenden
Bricklayer by trade 30 years We do extensions, alterations, loft conversions, orangries all types of roofing we also do new cement board cladding and all types of fencing
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Latest review:
Extensions- 16 Mar 2022
The extension has come out great and we are very pleased with the space gained. The bathroom is stunning. Ian was very approachable to discuss details and make changes through the job.
Sami
Rating: 5 out of 5
Extension Builder in Harpenden
Hi, I am a fully skilled plastering with 15 years of experience delivering quality work to your home.I also have experience in all other relating trades like external wall insulation,silicon rendering ect.
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Latest review:
Plastering- 28 May 2026
Came on short notice. Completed the job ontime and very nice work
Emanuel. Sh
Rating: 5 out of 5
Extension Builder in Harpenden
Hello everyone My name is Emanuel. I’ve used this app for a long time as well as a few other apps. I’m a builder for 8 years now. Me and my team can do everything regarding building work such as new builds, extensions, loft conversions, sheds, patio, fencing, roofs, garden work, plasterboard , skimming, painting,everything inside the house and out If you see me as the person to work in your house, I’m more then happy to help Thank you
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Latest review:
Bricklaying- 15 Feb 2023
Emanuel was hired because he seemed knowledgeable about his trade and came across as a confident tradesman. He was punctual and worked with professionalism. He offered to advise where his input was needed. Overall I am pleased with his work and will hire him again or recommend him to family and friends.
Compact Building Ltd
Rating: 4.8 out of 5
Extension Builder in Harpenden
Compact Building LTD Renovations | Refurbishments | Plumbing – Across London From full home makeovers to small upgrades, we deliver expert results with 0% interest payment options. Make It Compact. Make It Perfect.
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Latest review:
Bathroom Fitting- 21 May 2026
Petru fitted a new shower tray. It was a complicated job due to the location of the piping. Petru was very meticulous and ensured he completed the job correctly and to a high standard.
T.M Construction.ltd
Rating: 5 out of 5
Extension Builder in Harpenden
TM Construction.ltd, established in 2007, is a trusted building company specialising in extensions, loft conversion,refurbishments, and general construction projects. With over 15 years of experience, the company is known for its high-quality workmanship, reliability, and customer-focused approach. From groundwork and structural works to finishing touches, TM Construction delivers complete building solutions on time and within budget.
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Latest review:
Roofing (Pitched)- 6 Mar 2026
Thomas was a pleasure to work with. Polite and accommodating. Would definitely hire him again.
Ceca Developments LTD
Rating: 5 out of 5
Extension Builder in Harpenden
Hael Construction Ltd, a proud member of the Federation of master builders, is a trusted construction company based in North London, delivering high-quality building services across the region. We specialise in new builds, extensions, loft conversions, renovations, groundworks, electrical installations, and plumbing. With a skilled team of qualified tradespeople and experienced project managers, we provide a complete service from design to completion. Our focus is on quality workmanship, transparent communication, and delivering projects on time and within budget.
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Latest review:
Extensions- 23 May 2022
Ceca Developments have done an outstanding work on our side and rear extension project, and we would definitely recommend this company. Firstly, they have offered a really competitive quote for the work and have been very transparent and detailed in regards to how long it will take to complete the project. Sebastjan has been a pleasure to deal with and was very helpful during the project, providing honest and useful recommendations and being available every time we needed anything. All the work has been completed to a very high standard and to the agreed timelines. We did not have to worry about anything during the whole project, which made this a very pleasant experience.
coppertree construction ltd
No reviews yet
Extension Builder in Harpenden
Coppertree Construction Ltd. we are a professional building company offering reliable construction solutions. we focus on quality workmanship, clear communication and results you can depend on. we specialise in single story extensions and house refurbishments.
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TJD Driveways & Landscape
No reviews yet
Extension Builder in Harpenden
My name is Tony. I'm a qualified bricklayer who has experience in New builds, extensions, footings, groundworks. I also specialise in driveways, patios and all aspects of landscapeing . I've always been tought to do the job right first time. I'm proud to say i produce exceptional work and standards. Clarified by every customer and building official I've worked with.
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Daniel Gagea
Rating: 5 out of 5
Extension Builder in Harpenden
We are onest builders, quick and reliable jobs, new on my builder but with lots of experience on the trade, looking for work, we do all kind of refurbish jobs, decorating, carpentry, basic plumbing and electric, new bathrooms or kitchens, back or loft extensions ,landscaping and much more We offer guarantee for our work. Everything seen on the pictures is 100% our work and we have loads of other pictures
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Latest review:
Daniel quoted comprehensively and clearly for both jobs that I needed, building an extension and a raised patio at the end of the garden. He worked extremely hard and diligently every day. Also he would summarise what he would do next and we discussed any changes etc and which tiles or render I preferred. I am very happy with both the patio and extension and Daniel finished everything off to an excellent standard and went above and beyond the quote. I would not hesitate to use him again and recommend him highly.
MSG DESIGN LTD
Rating: 5 out of 5
Extension Builder in Harpenden
Hello I am Simion, the proud owner of Msg Design Ltd , A little about us With many happy and returning customers over the last 7 years, you can be sure of being well looked after. Our aim is to provide a stress free project, delivered in a manner that I am confident will exceed your expectations. I work with a small team of trusted colleagues, who communicate and work together well. Our customers are accustomed the outstanding quality of projects we complete, by sourcing quality materials with experienced installers we create truly bespoke masterpieces lasting our customers many years. 2 year guarantees are included as standard on all completed work. Availability We are always contactable via phone throughout the week, including evenings and weekends. If for any reason you are unable to contact us, please send a text message or email. Thank you for taking the time to consider our company’s profile, I look forward to hearing from you. Msg Design Ltd
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Latest review:
Carpentry- 7 Jun 2026
Top carpenter. Will definitely be using again. Neat and great craftmanship.
DJP BUILDING SERVICES
No reviews yet
Extension Builder in Harpenden
General building company specialising in groundwork, brickwork and plastering.
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Gazmend
No reviews yet
Extension Builder in Harpenden
Hi my name is Gaz, I do extensions from start to finish, loft conversion, Garden refurbishment and patio, Best prices around guaranteed Don’t hesitate to give me a call
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Jay Truslove
No reviews yet
Extension Builder in Harpenden
Been roofing for 20+ years and went into building about 15 years ago. All aspects of work undertaken.
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Jr general building
Rating: 5 out of 5
Extension Builder in Harpenden
Professional Builders JR General Building Ltd is a fully-insured, limited company with a heritage spanning three generations. We excel in delivering comprehensive building services, from foundational work to chimney construction. Our specialised departments are staffed by fully-qualified professionals, ensuring all your requirements are met to the highest standards. As an SMAS-accredited organisation, we take safety seriously. Every member of our team holds a CSCS registration, guaranteeing not just an exceptional finished project, but also a commitment to conducting work in a safe and secure manner. 20+ years experience 500+ projects 100% customer satisfaction
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Latest review:
Driveways (Paved & Loose)- 23 Oct 2023
Very pleased with the repair work on my block paved driveway. Jamie and Lee were very professional and helpful. Job was completed quickly and at a reasonable price. I would use them again!

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.