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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Builder Cat LTD
Rating: 5 out of 5
Extension Builder in Hertfordshire
Serdar has over 20 years of experience as a professional builder. His extensive experience includes Owner/Builder/Developer of his own company, many years Builder Cat Limited was founded by Serdar Aydinlar, who has since 1996 structural engineering and design experience. Serdar oversees the structure of each project, and monitors the careful execution of the design brief to ensure a flawless finish.
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Latest review:
Bathroom Fitting- 12 Jun 2019
Did a very good and efficient job with minimum fuss. I have asked the builder to quote for another job and do not have any hesitation in recommending this builder.
D price brickwork
No reviews yet
Extension Builder in Hertfordshire
Hi my name is David , I have been doing bricklaying and structural alterations since leaving college. I have over 25 years of experience in the building game
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A and B Gardening LTD
Rating: 5 out of 5
Extension Builder in Hertfordshire
Here at A&B Group, we have years of hands‑on experience across a wide range of trade needs, from landscaping to renovation and refurbishment projects, our company brings reliable expertise to every job we take on. We proudly serve clients throughout Hitchin and the surrounding areas, offering flexible travel for projects of all sizes. Our specialist skills include high‑quality finishing, problem‑solving on complex builds, and delivering clean, precise workmanship from start to finish. Customers choose us because we prioritise clear communication, honest advice, and craftsmanship that stands the test of time, ensuring every project is completed to the highest standard. Delivering your work from start to finish, with near all trades covered in-house. Built on Trust. Delivered with Quality. Check out our instagram: aandbgardening aandbconstructiongw
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Latest review:
Extensions- 24 Sep 2026
Was a pleasure to work with this company.
Johnny Construction
Rating: 5 out of 5
Extension Builder in Hertfordshire
I’m a realible person good and hard worker with lots knowledge in the construction industry
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Latest review:
Hard Flooring- 31 Oct 2026
Arrived on time and carried out the work professionally. Was very helpful and insightful and left the room tidy when finished. Very happy and will recommend and use again! Thank you so much!
Benington Services
No reviews yet
Extension Builder in Hertfordshire
We have an exceptional team of qualified staff with years of experience who take pride in carrying out an excellent service.
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PrimeUKContractorsLtd
Rating: 5 out of 5
Extension Builder in Hertfordshire
Prime UK Contractors is a London-based construction company providing high quality work for a reasonable price. Our projects are always finished on time. Our priority is the satisfaction of our clients. Our team consists of skilled, experienced builders who will help you execute your dream project.
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Latest review:
I recently used PrimeUK Contractors Limited for conversion works at our studios in Camden, and I couldn’t be happier with the results. The project timeline was set at six weeks, and the team delivered right on schedule. Pavlo and his team had a clear understanding of the scope and what needed to be achieved, going above and beyond to make the project a success. The quality and attention to detail in their work were outstanding, and my entire team was thrilled with the final result. Their pricing was competitive and fair, which was another bonus. When we have more work in the pipeline, Pavlo and PrimeUK will definitely be my first call. Highly recommend!
Dj Russell builders limited
Rating: 5 out of 5
Extension Builder in Hertfordshire
We are a building company which cover a multitude of trades in the industry. We pride ourselves on quality and good working relationships with all our clients. We have been trading for over forty years and have built up a good reputation with local authorities and domestic clients alike. We cover all building and maintenance aspects in the private and public sector.
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Latest review:
Extensions- 14 Feb 2021
Adam and the DJ Russell team have been great, I cannot recommend them highly enough. The job started on the 3rd of November 2020 and was completed on the 3rd of February 2021. All the neighbourhood have been impressed with the speed and accuracy of workmanship displayed. From the general builders (Bruce, Martin and Steve) to the brickies (Paul, Matt and Steve) and to the carpenters (Paolo and Dominic) through to the electricians (Max and his team) and the plumbers (Mark and Jack) and last but not least the plasterers (Gary and Craig) they all have kept me occupied with producing huge quantities of tea and coffee (-: but most of all they have constructed a quality extension for our home. Thank you for all your hard work and professionalism.
George
Rating: 5 out of 5
Extension Builder in Hertfordshire
Mini digger and driver hire and I’m specialist in bricklaying , choose me if you need something to dig cheap Thanks
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Latest review:
Groundwork & Foundations- 7 Jun 2023
Did has work quickly
Florin
Rating: 5 out of 5
Extension Builder in Hertfordshire
I’ve got over 10 years experience in roofing industry,I’m a professional person,I’m not doing tipe of work that I never done it before,I don’t leave any jobs unfinished.I have done several roofing jobs for different companies base in London.
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Latest review:
Roofing (Pitched)- 29 Nov 2022
Florin and his team did a very good job fitting a skylight and rubber roof. Communication was very good and the standard of workmanship and overall finish were excellent. I would strongly recommend him
JBP Developments Ltd
No reviews yet
Extension Builder in Hertfordshire
1. Surveys - Offering drone and Matterport surveys for planning applications and marketing purposes 2. Architectural Services - Providing drawings for pre-app and planning submissions. 3. Project Management - Managing multiple consultants, sub-contractors, and statutory authorities at any stage of the construction process. 4. Design and Build
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RMR Building & Renovation
Rating: 5 out of 5
Extension Builder in Hertfordshire
Welcome to RMR Building & Renovation Ltd — your trusted partner for high-quality building and property transformations. Based in Harlow, we proudly serve homeowners across Essex, London, Cambridge, and surrounding areas within a 50-mile radius. With over 15 years of industry experience, we pride ourselves on exceptional craftsmanship, reliability, and clear communication. From small residential updates to major structural overhauls, our fully qualified and insured team manages every project with absolute precision. Core Services Include: • Extensions & Conversions: House extensions, structural wall removals, and garage conversions. • Full Renovations: Kitchen installations, bathroom refits, and complete property updates. • Groundworks & Brickwork: Foundations, drainage, excavation, and structural brickwork. • General Building: Plastering, rendering, screeding, and interior/exterior decorating. Why choose us? • Experienced Specialists: Over 15 years of hands-on expertise in extensions and renovations. • Fully Insured: Absolute peace of mind with complete liability insurance. • Turnkey Solutions: We manage your project from groundworks to the final brushstroke. • Clean & Professional: We treat your home with respect, ensuring a tidy site and minimal disruption. No matter the size of your project, we are committed to delivering on time, on budget, and to the highest standard. Get in touch today for a free, transparent quote!
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Latest review:
Restoration & Refurbishment- 24 Aug 2025
Rez and the Team have done an excellent job with the complete bathroom renovation and additional decorating works, laminate flooring in the hall and living room, along with plumbing and electric tasks. Very professional, with great communication and finished all works to a high standard within the estimated time, accommodating all changes as the works went. Very grateful also for tackling the bathroom wall tiles pattern, which turned out to be exactly as planned.
Adrian
Rating: 5 out of 5
Extension Builder in Hertfordshire
Ady Construction Services LTD is a full-service building company providing high-quality construction, renovation, and property maintenance solutions across residential and commercial sectors. From groundwork, brickwork, roofing, and extensions to full refurbishments, kitchen and bathroom installations, landscaping, and decorating, we cover every aspect of building work. With a skilled team, attention to detail, and a commitment to excellence, we deliver reliable and cost-effective services tailored to each client’s needs — from start to finish.
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Latest review:
Landscaping- 23 Mar 2025
Great job - promptly done and good quality!
B&G Brothers Construction Ltd
Rating: 4.8 out of 5
Extension Builder in Hertfordshire
WELCOME TO B&G BROTHERS CONSTRUCTION LTD B&G Brothers Construction Ltd is a well-established building company based in Stanmore North West London. We carry out most types of building works, including: House Extensions Property Refurbishments Loft Conversions Ground Works And all type of repairs and alterations. You can be confident in our abilities to create you that perfect home using the highest quality of materials and best possible level of workmanship
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Latest review:
Extensions- 11 Jan 2023
Rear garden extension done with new fully refurbished old house new electric new plumbing, all work done properly and good quality, experienced builders , +++ big job done within time frame and olso garden levelling with retaining wall ! Andrei and Alex recommend!
RT Build
Rating: 5 out of 5
Extension Builder in Hertfordshire
We are a family run small company with 20 years on the market.We specialize in bathroom ,kitchen and general building refurbishments.We offer high quality service for a reasonable price with great attention to details. Your satisfaction is our top priority.We are looking forward to doing new project with you.
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Latest review:
Bathroom Fitting- 27 Dec 2025
Rafal did everything as expected. Many thanks for his commitment and professionalism.
THE OREILLY GROUP LTD
Rating: 5 out of 5
Extension Builder in Hertfordshire
We undertake all Groundworks packages to simple repairs to large site packages.Having been in the industry almost 20 I have worked on a number of large scale projects including RAF Northolt,Harry Potter world London and many housing developments. All our lads are fully trained and certified,including Cscs,Cpcs,first aid etc.We own all our own plant from 1 tonne to 30 tonne excavators, dumpers, skips and grab lorrys.Here at The OReilly Group we pride ourselves on repeat business & recommendations
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Latest review:
Groundwork & Foundations- 25 Jul 2023
The Oreilly Group completed my groundworks, external drainage and some knock throughs on my extension. The job commenced when promised and was completed within programme. The works were completed on time and this included some extras I threw in along the way. I would reccomend Owens team for any groundwork and drainage project - very happy with the outcome.
Access Building and Construction Ltd
No reviews yet
Extension Builder in Hertfordshire
Hi Access Building and Construction are a family owned and run building and construction that specialise in all general building works to include Garage Conversions, Extensions, ramping, internal refurbishments and bathrooms. With over 30 years experience in the building industry and a 5 star rating (through our sister company) we can offer a full design, supply and installation service. We have our own tradespersons to make sure all aspects of our projects are completed in full. We have our own in house project manager to make sure your project runs on time, on schedule and in budget. Building applications, structural reports and Part L calculations are all carried out in house to help keep your cost down. We offer a full 10 year warranty for all building works and 5 years warranty for bathrooms, along with a 5 million pound public liability insurance. As members of the BHTA we could offer zero rated VAT if any work is carried out for mobility, easy access or ground floor living. We also have a legal contract approved by the trading standards code of practice, all for your piece of mind. Kind regards Lee Brand CEO
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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.

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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.