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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Johnstones Property Services
Rating: 4.4 out of 5
Extension Builder in Hertfordshire
25 years experience in the building trade. Running my own business for 15 years. More than just decorators; I have a team who can complete a variety of building related tasks. We specialise in complete property refurbishments and are a proud member of the The Guild of Mastercraftsman.
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Latest review:
Extensions- 27 May 2021
Very professional service. Extremely happy with the finished result. Polite and friendly builders and admin team. Would definitely recommend and I'll be using these guys again in the future. Thanks again.
BARNETTS BESPOKE
Rating: 5 out of 5
Extension Builder in Hertfordshire
At Barnetts-bespoke we specialise in high quality custom carpentry and building solutions tailored to your unique needs, proudly serving all areas of Hertfordshire and London we offer high end craftsmanship for a wide range of projects including bespoke wardrobes, kitchens, bespoke storage solutions, and complete renovations Our complete list of services are listed below *kitchens *bathrooms *extensions * bespoke wardrobes/cabinetry *roofing *flooring * summerhouses * Returbishments * new build
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Latest review:
Carpentry- 11 May 2020
Charlie was absolutely brilliant, fist class tradesmen with extremely high standards Will definitely use and recomend to others
Aston Brickwork
Rating: 5 out of 5
Extension Builder in Hertfordshire
My name is Sean Aston I have been a bricklayer for 6 years now. I have all kinds of experience, from working on a large construction site to smaller jobs such as extensions ,porch's and garden walls. Any and all tradesmen I use will be full qualified I also have all relevant insurance .
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Latest review:
Bricklaying- 30 May 2019
Sean was on time and very polite at all times. He completed the work very efficiently with no disruption whatsoever. He went out of his way to make sure the job was completed to our satisfaction. He cleared up afterwards and left the site very tidy. We would happily recommend Sean.
OFIX Ltd
Rating: 5 out of 5
Extension Builder in Hertfordshire
With over 34 years experience I offer a complete design and build package as well as providing specific services for smaller contracts. I have been vetted by the Federation of Master Builders and strive to provide excellence. I am an extremely competent multi trader with a good eye for detail. With a team of experienced subcontractors I will deliver incredible quality installations on time within budget.
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Latest review:
Carpentry- 8 Mar 2025
Absolutely over the moon with Mike, he did a fabulous job. Would definitely recommend him!
P Jordan and Sons Ltd
Rating: 5 out of 5
Extension Builder in Hertfordshire
Jordan & Sons are a family run business with over 30 years experience specialising in extensions, new builds, all types of groundwork, drainage, brickwork, driveways, patios, resin bound & block paving. The work we carry out is second to none, finished to a high standard while providing an excellent service. We own our own plant with relevant tickets, & we take on all commercial and domestic projects.
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Latest review:
Extensions- 20 Aug 2026
We’re extremely pleased with the new garage build. From start to finish, the team were hardworking, punctual and professional. Communication was excellent throughout, and they kept us informed at every stage of the project. The quality of the work is great, and the whole process was completed efficiently and with great attention to detail. We wouldn’t hesitate to use them again and would highly recommend them to anyone looking for a reliable and professional builder.
B & M Home Improvement
Rating: 5 out of 5
Extension Builder in Hertfordshire
We are a local and reliable Plumbing, gas safe and Home Improvement Company in London and surrounding areas.I gained my experience working in the Plumbing and gas department. No matter whether you require help with plumbing, power flushing, boiler installation, bathroom, kitchen, extention, flooring we take on all building work. We provide a full interior decorating service for domestic and commercial.
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Latest review:
Extensions- 10 Apr 2014
Max and Bob completed the extension on time and within budget. There were no hidden extras and despite Bob being on holiday for two weeks, Max worked hard and lon. The extension is 6m x 5m. There were issues with Building Control which Max sorted out and did everything to meet their requirements. The extension is built to a high standard, kitchen cabinets fitted well, tiling very good and we are pleased with the quality of their work. We are using B&M again as we are confident that although they are not tghe cheapest, the quality of their work is of a high standard. Besides, it is always a pleasure to deal with Max who is a gentleman, patient and listens to what is required.
Ladkarn Construction Limited
Rating: 5 out of 5
Extension Builder in Hertfordshire
We are a well established construction company with very high expectations and standards of work. We are fully insured and carry out groundworks and landscaping and have a very professional team of operatives ensuring the quality of the works completed match our very high standards. We can carry out larger projects relating to the full construction of houses, extensions or conversions.
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Latest review:
Groundwork & Foundations- 11 Jul 2026
James is just brilliant! Did a great job.
Pat Mcgeough
Rating: 4.9 out of 5
Extension Builder in Hertfordshire
McGeough & Sons Ltd is a family run business based in Bedfordshire. I am a time served carpenter with 27 years extensive experience in all aspects of refurbishments and building. Fully insured, contact us for a non obligated quote or advice
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Latest review:
Conversions - General- 4 Jan 2026
Pat was a pleasure to deal with from beginning to end he had everything covered and made the whole project a seamless experience. He provided me with a professional quote and had the patience to deal with my questions. He started the project on time svd no thing was too much trouble, when I needed a roofer to fix some issues with a leak he had someone on the job within a day. He handled every aspect of my garage conversion effortlessly and had the job finished on time right before Xmas. Would 100% use Pat again. Great guy who also knows good trades people. Thanks Pat.
AMT Property Solutions
Rating: 4.9 out of 5
Extension Builder in Hertfordshire
I have spent 40 years in the construction industry, starting straight from school where I completed a five-year apprenticeship in the glass and glazing industry. Over the years, I progressed through all areas of the window and fenestration sector, gaining extensive hands-on experience in all types of glazing, window systems, fire doors, conservatories, and associated installation works. As my career developed, I broadened my expertise further by moving into carpentry and developing practical skills in a range of additional trades, including brickwork, tiling, kitchen fitting, and general building works, to name a few. This diverse background allows me to offer a well-rounded understanding of both specialist and general construction projects. We operate throughout Bedfordshire, Hertfordshire, Northamptonshire, and Oxfordshire, including all surrounding areas.
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Latest review:
Windows & Doors (uPVC & Metal)- 28 Sep 2026
Fantastic service thank you! Felt like a silly little job but was done perfect and would rehire! Came across an issue with the glass that was cut but instantly sorted out another one.
The Mangrove Group
Rating: 5 out of 5
Extension Builder in Hertfordshire
We do a vast amount of work from extensions and loft conversions to fences and garden walls. We’re a family run business that will work with our clients to ensure they get what is aesthetically pleasing and long lasting.
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Latest review:
7 months ago loft alteration. All work to the roof and brickwork completed efficiently and in excellent time. windows, doors, and flooring fitted perfectly Very pleasant polite and professional Builders. would genuinely recommend .
Milestone Brickwork
Rating: 5 out of 5
Extension Builder in Hertfordshire
Local bricklayer based in herts and Essex, we also undertake patios and fences.
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Latest review:
Jack came and quoted to lay a new patio and a shed base. He listened to exactly what I wanted (something other workmen didn’t do!) and came back with a very reasonable quote and said he would complete the job on a weekend as I wanted it done asap. From start to finish Jack was really polite and friendly and worked really hard to get the job finished - so much so, I’m adding more bits to the garden and will get Jack back over to do it!
NOVATE ACS LTD
Rating: 3 out of 5
Extension Builder in Hertfordshire
NOVATE ACS LTD, you can see more detail on our services on our website. We are an innovative design led London based Chartered RIBA Architectural Practice and an Accredited Construction Company. We specialise in home extensions, loft conversions, refurbishments and new builds
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Latest review:
Architecture- 21 Dec 2024
Good rating and very helpful.
GSrenovation
Rating: 4.9 out of 5
Extension Builder in Hertfordshire
We have 25 years of property renovation .During the last 15 years GSrenovation has specialised in fitting and renovating bathrooms, kitchens and extensions . We believe that our success stems from our exacting professionalism and true enjoyment of our work. We take as long as is needed to help customers from design through to completion. For peace of mind GSrenovation also provides 5 years guarantee with each installation. Sensible prices. Free quotation and advice.
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Latest review:
Kitchen Fitting- 10 Jul 2024
George has done an excellent job. He is highly recommended, and his prices are reasonable.
CNR Bricklaying & Building Services
Rating: 5 out of 5
Extension Builder in Hertfordshire
CNR Bricklaying & Building Services. A friendly, family run brickwork business who speialise in all types of brickwork and restoration.
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Latest review:
Bricklaying- 19 Apr 2016
We have always found it a problem trying to match the correct tradesman to any work we have needed doing, so much so that many jobs have been left undone. You either end up with a personality clash, or just plain bad workmanship, well not this time. The entire process was a joy from start to finish, from the initial quoting process, to the completion and the standard of work was exemplary. Nothing seemed to be a problem for them and they were very pleasant to have around. We are busy drawing up a fresh list of jobs we need doing and would certainly thoroughly recommend them. If you have had any bad experiences in the past, give them a try, you will be very satisfied.
B Williams groundwork & brickwork
No reviews yet
Extension Builder in Hertfordshire
All groundwork/ foundations and brickwork/ blockwork. 20+ years experience
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Flori plasterer
Rating: 5 out of 5
Extension Builder in Hertfordshire
👋 Welcome to my page! I’m a professional plasterer and renderer with 13 years of experience in the trade. We specialise in all types of plastering and rendering, including internal and external work, and can also take care of any additional construction work required to complete your project. 🏠 Quality workmanship 🔨 13+ years of experience ✅ Reliable and professional service 📍 Domestic & commercial projects Whether it’s a small repair or a full house renovation, feel free to get in touch for a free quote or advice. Thank you for visiting my page! 🙌
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Latest review:
Plastering- 9 Oct 2026
Very nice finish did a good job , would recommend!

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.

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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.