Extension builders in Hertfordshire

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.6 (18 reviews)

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Some of our top rated extension builders in Hertfordshire

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Tim Lee Construction and Development
No reviews yet
Extension Builder in Hertfordshire
A small family run business with over 30 years experience within the building trade. Specialising in structural alterations and conversions. Kitchen design, supply and installation. All professional trades you will need to complete your project.
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Jonner Construction
Rating: 5 out of 5
Extension Builder in Hertfordshire
Hello! We are a team of passionate craftsmen with 20 years of building experience between us. Our main focus is first & second fit carpentry & joinery but we also provide most types of general building & maintenance services. We cover a large area from Stanmore to Basingstoke. We take pride in what we do, our goal is to complete jobs to satisfaction once without need to return. We love what we do and no challenge is too big for us, in fact we welcome challenges as it grows us further in our craft! Hire us if you would like a quality job completed in a professional and timely manner, with full, transparent communication from start to finish. We will make sure you are satisfied & bring your ideas to reality! Thank you for taking the time to read & we look forward to working with you on your projects!
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Latest review:
Carpentry- 9 Jul 2025
Michael came gave a reasonable and well broken down quote and saved our timber bifolds that no on else would touch. We should get many more years from these before we need to replace now! I would definitely recommend Michael and Jonner Construction.
Geo Way Limited
Rating: 5 out of 5
Extension Builder in Hertfordshire
The "Geo Way Limited" is trustful FMB member construction company with professional experienced team with all required qualifications & DBS checked; we undertake works listed below: - Brickwork - Extension works - Loft conversion - Interior Designing - Kitchen & Bathroom installation - Decorating - Flooring - Bespoke joinery - Carpentry - Plastering - Dry-lining
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Latest review:
Kitchen Fitting- 19 Sep 2021
Zaza of Geo Way's Ltd was such a nice person to work with. As an individual who doesn't have a clue about building work and where to get materials he helped throughout. I didnt feel taken advantage of at all. Very professional people to work with. I would given them 10/10. Thank you Zaza and team.
E&E construction
Rating: 5 out of 5
Extension Builder in Hertfordshire
With over 18 years of industry experience, our construction company specializes in high-quality house extensions and loft conversions across London and Essex. We are committed to transforming homes with expert craftsmanship, tailored design solutions, and reliable project management from start to finish. Whether you're looking to expand your living space, increase property value, or bring new life to your home, we deliver outstanding results that reflect your vision and meet the highest standards of construction excellence.
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Latest review:
Fencing- 9 Sep 2023
Ervin was polite, communicated well and worked hard to get the job done. Would hire again.
grantconstruction0
Rating: 5 out of 5
Extension Builder in Hertfordshire
The construction company carries out and performs a full range of complex interior finishing works, general contracting for the repair and reconstruction of buildings and premises in commercial areas. The main direction in which the company operates is commercial real estate: shopping, entertainment and office centers, factories, hotels, logistics complexes and scattered throughout London will undertake any repair and restoration work. We use only high-quality materials and tools to ensure the highest quality of work, in addition, we always adhere to the agreed deadlines and budget, which allows our clients to be confident that the repair work will be completed on time and without unnecessary costs
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Latest review:
Tiling- 4 Oct 2026
After some confusion about when arriving. Went well. Ensure clear understanding, prior to work starting, on who is providing materials while agreeing costs. Would recommend.
Amwell Build Limited
No reviews yet
Extension Builder in Hertfordshire
Family Business run for over 30 years, we do jobs from Patios to Complete Newbuilds start to finish, no job to big or small, were the guys for your project
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KFN Plastering & Property Maintenance
Rating: 4.8 out of 5
Extension Builder in Hertfordshire
KFN Plastering & Property Maintenance is a trusted and professional company with over 18 years of industry experience. Based in Watford, we take pride in delivering exceptional workmanship, attention to detail, and outstanding customer service on every project. Fully vetted and committed to the highest standards, we provide reliable plastering and property maintenance services tailored to meet our clients’ needs. Whether undertaking small repairs or larger renovation projects, we consistently deliver a high-quality finish with a focus on professionalism, cleanliness, and customer satisfaction.
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Latest review:
Plastering- 19 Jul 2026
Excellent plasterer! Karl did an outstanding job, and the quality of the plastering was excellent, with a smooth, professional finish throughout. He turned up on time every day, completed the job on schedule, kept everything tidy, and was friendly and easy to deal with. I’m very happy with the result and would definitely recommend Karl to anyone looking for a reliable and skilled plasterer.
Brent Property Services LTD
Rating: 5 out of 5
Extension Builder in Hertfordshire
We are a building and refurbishment company. We are not the type of team that we can do everything, in our team the plumber is plumber , electrician is not bricklayer as well, everyone is doing what they trained for. Works are insured, reference available. At request we provide gas safety certificate and electrical certificate.
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Latest review:
Restoration & Refurbishment- 18 Sep 2019
Work completed to a good standard. Thank you
Circle Construction Ltd
Rating: 5 out of 5
Extension Builder in Hertfordshire
….………. Circle Construction Ltd is an established building company based in Hemel Hempstead, covering all residential construction works in Hertfordshire, Bedfordshire and all surrounding counties. Specialities are bricklaying (14 years experience), extensions, new builds, loft conversions, landscaping and groundwork’s.
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Latest review:
Landscaping- 4 Oct 2020
Jack did our patio and front path and we couldn't be happier. He is very positive and enthusiastic and kept us up to date with the process from beginning to end. He prices jobs very reasonably. We will definitely use him again.
BNN CONSTRUCTION LTD
No reviews yet
Extension Builder in Hertfordshire
I have 5 years of experience working for my self i have been in construction since i was 15 my company is undertaking all grenrall building work all jobs all sizes are considered
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Dignity LC Services Ltd
No reviews yet
Extension Builder in Hertfordshire
I have been running my own building and construction business for approx 30 years, with over 35 years of industry experience. I am a fully skilled carpenter by trade but have vast amounts of knowledge and experience in all aspects of building and construction works. The work I undertake includes domestic building; extensions, conversions, kitchens and bathroom, disabled adaptations.
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Sphinx constructions ltd
New on MyBuilder
Extension Builder in Hertfordshire
Looking to expand your home with a high-quality extension or loft conversion? With over 300 successful projects completed in the past 8 years, all certified to meet building regulations, we deliver exceptional craftsmanship you can trust. Transform your space today—contact us for a free consultation!
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AVR Construction
Rating: 5 out of 5
Extension Builder in Hertfordshire
I have a 10 years in construction industry ( landscaping) dancing paving foundations and many more For a fare quote contact me .
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Latest review:
Groundwork & Foundations- 21 Oct 2026
Excellent work and arrived on time
Michael John Interiors
Rating: 5 out of 5
Extension Builder in Hertfordshire
Hi I'm a general builder, started my working life on kitchen & interior design then also Installations, which quickly lead to building works. Taking down walls to building large extensions/loft conversions & out side works We take on any size work & can offer lots of advice & design help, having 35 years experience From kitchen installations & all types of Interior work To extensions/outside works & loft conversions.
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Latest review:
Extensions- 15 Apr 2019
Submitted quote on time and has responded to all questions and been very helpful.
PWF CONSTRUCTION LTD
Rating: 5 out of 5
Extension Builder in Hertfordshire
FRIENDLY, POLITE AND CONSCIENTIOUS
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Latest review:
PWF construction were never hired to complete my job and the fact that I am now writing a review is an error on my part. Paul Fisher was however very helpful when he provided a quotation for my job and his communication was great.
Abbot's
No reviews yet
Extension Builder in Hertfordshire
Hello
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4.6

Top rated Extension Builders

Our Extension Builders in Hertfordshire, are rated 4.6 out of 5 based on 18 reviews from customers like you.

Quality screening

Easily find verified local tradespeople. Just post your job to get quotes from tradespeople near you across the UK.

What types of services are offered by local extension builders in Hertfordshire?

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 Hertfordshire 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 Hertfordshire who are available and interested can respond to your post.

Browse profiles, read customer reviews and get quotes from your chosen Hertfordshire extension builders, all before you decide who to hire.

What are the hourly rates of extension builders in Hertfordshire?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Hertfordshire 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 Hertfordshire extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Hertfordshire home extension project is likely to cost.

Find extension builders in Hertfordshire with MyBuilder

Hiring the right extension builder in Hertfordshire 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 Hertfordshire extension builders. Once your job is live, we’ll share it with home extension builders in Hertfordshire who can express their interest.

Step 2: Compare different extension builders in Hertfordshire

When you start receiving interest, review profiles of local Hertfordshire extension builders, check their previous work, and read real customer reviews. Ask about timelines, materials, and request detailed quotes.

Step 3: Hire Hertfordshire extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Hertfordshire, 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.

Hertfordshire extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Hertfordshire extension builder before hiring?

Before hiring an extension builder in Hertfordshire or extension building company in Hertfordshire, 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 Hertfordshire?

An extension builder in Hertfordshire 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 Hertfordshire 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 Hertfordshire?

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 Hertfordshire 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 Hertfordshire 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 Hertfordshire

Can an extension builder in Hertfordshire help with planning permission?

Yes, many extension builders in Hertfordshire 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 Hertfordshire handle everything from design to construction?

Many Hertfordshire 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 Hertfordshire help with materials and finishes?

Yes, most extension builders in Hertfordshire 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.