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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Johny the Builder
Rating: 5 out of 5
Extension Builder in Hertfordshire
PROFESSIONAL BUILDERS. Johny The Builder Ltd are Building Contractors based in Romford, Essex. We undertake commercial and domestic Refurbishments, Roofing, Loft conversions, Brickwork, Extensions, Basements and new building projects. We make your House a Home
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Latest review:
Extensions- 28 Sep 2018
Johnny was very nice to deal with. When there were problems they were quick to find ways to rectify them. They started at short notice& finished on time which I was very impressive. We got a no. of quotes,Johnny was middle of the range but with a better level of service than others. Johnny was very open about when things might cost more &gave us the option if we wanted to proceed. A few things to note: -this was our 1st experience of any building work &we should have remembered they are builders, not designers -we both work long hours &so most days didn't see the team to get an update or brief them. This meant a few things were missed or miscommunicated - while most of the team were lovely the electrician used was horrible to deal with. He got very cross about requested changes, didn't deliver everything requested &just did silly things like putting in a light switch with 2buttons where there was only one Light or hanging lights incredibly low when we had given measurements of where we wanted them - we got Johnny's team to build some extra storage for us which on the whole was fine but some things weren't centred or for example the wine rack they built was wonky Overall, it was a good experience and we would recommend them but would suggest be home to oversee the work more than once a week (must be true of any building work!) and get your own electrician. Very happy to talk to people and give references-the house looks great now.
TD Building
No reviews yet
Extension Builder in Hertfordshire
Fluent in Turkish. I have 45 years of experiencing construction that have worked in all areas including high-rise buildings and rough construction metal work measurements. I understand every part of the process and always deliver quality work. Written by the son of the builder.
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F&U Building Construction
Rating: 4.7 out of 5
Extension Builder in Hertfordshire
All aspects of building work covered professionally. Always willing to go the extra mile. Very low prices. * Extensions/ Conversions. * Full kitchen fitting. * Full bathroom fitting. * Painting/ wallpapering. * Chimney removal. * Plastering. * Tiling. * Double glazing/bifolds. * All Diy handyman works Covering Barking, Dagnem, Romford, Ilford, Gant's hill, Leyton, Leytonstone, Walthamstow, Woodford, all areas in East London, please ask.
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Latest review:
Carpentry- 10 Oct 2022
Athar and his team did a brilliant job to a very high spec with a good price. I am very happy with work done. Would highly recommend
Jaspal
Rating: 5 out of 5
Extension Builder in Hertfordshire
Hi,i work very well and im very carefull about thier work.
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Latest review:
Plastering- 25 Sep 2026
Reasonable priced. Timely finished. Remained on contact. Very nice person and a good personality. Well done Jaspal and thank you for your work.
Total B Construction Ltd
No reviews yet
Extension Builder in Hertfordshire
Total B Construction Ltd are leading main contractors providing end-to-end design, construction, and commercial/residential project delivery across London and the South East. Under the executive direction of NVQ Level 7 Project Management, our group operates with corporate precision, rigorous HSE compliance, and dedicated site supervision on every contract. Our Specialized Divisions: • Main Contracting & Refurbishments: Full-scale residential developments, commercial-to-residential conversions, and structural remodeling. • High-End Interior Fit-Outs: Bespoke joinery, architectural tiling, luxury wet rooms, and premium finishes executed by master trades. • Sustainable & Eco Construction: Modern Methods of Construction (MMC), Structurally Insulated Panels (SIPs), and energy-efficient building systems. Why Enterprise & Residential Clients Partner With Us: • Senior Project Oversight: Managed directly by NVQ Level 7 certified leadership to guarantee deadline compliance and budget accuracy. • Full Regulatory Compliance: Fully insured, CDM compliant, with strict quality assurance (QA) frameworks. • Scalable Workforce: Capacity to handle concurrent, multi-phase projects without compromising on execution speed or quality. Contact our commercial team today to schedule an initial consultation or tender review.
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DOREZ LTD
No reviews yet
Extension Builder in Hertfordshire
Dorez Ltd is a company that specialises in refurbishment and new build projects. We have a team of directly employed professional staff who deliver a cost-effective, timely, and high-quality construction solution. Our core team of tradesmen delivers consistent quality and has the ability to be flexible and reactive to requirements. Dorez Ltd was created in 2013 by Ermal Brazhda the owner and the person responsible for delivering every project from beginning to the end . We cover all the London areas We work outside London that’s depends on the projects . Get in touch today for better quality !
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Your Space
No reviews yet
Extension Builder in Hertfordshire
We create the perfect space you require. You choose, we build. We can assist, from design, all the way to the finished article. All aspects of buildings works are carried out.
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Marco ltd
Rating: 4.6 out of 5
Extension Builder in Hertfordshire
we put effort and commitment into our work so that the client is satisfied with our work
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Latest review:
Hard Flooring- 1 Sep 2026
I WANTED TO LEAVE A MINUS REVIEW BUT THERE IS NONE, THAT IS WHY I HAVE LEFT THE LEAST POSSIBLE SCORE. I PERSONALLY DO NOT THINK THIS GUY CALLED MARCO KNOWS ANYTHING ABOUT BUILDING AT ALL. HE IS A ROGUE BUILDER. HE SAID HE HAS 25 YEARS BUILDING EXPERIENCE, WHICH IS A LIE. I CALLED HIM TO DO MY FLOORING, KITCHEN CABINET, TOILET. PAINTING, FIXING LEAKS. HE RUINED THE WHOLE HOUSE. 8 MONTHS ON, WE ARE STILL REDOING ALL THE WORKS HE DID, HE JUST SPLASHED SILICONE ON THE UPVC TO FIX A LEAK. THE LEAK CAME THROUGH THE CEILING UNTO THE FLOOR CAUSING A BIG FLOOD IN THE HOUSE. HE IS THE MOST UNTIDY BUILDER. HE SAID HE WAS PAINTING, HE SPLASHED PAINT ALL OVER THE HOUSE, HE KEPT SAYING HE WILL TIDY IT UP AT THE END. UP TILL NOW, 8 MONTHS AFTER, I AM CLEARING THE MESS. ALL THE GROUT HE PUT ON THE TILES CAME OFF THE FIRST TIME I MOPPED THE KITCHEN FLOOR. ALL THE TILES HAVE MARKED PAIINT ON THEM AND IT IS EXTREMELY DIFFICULT TO REMOVE THEM BECAUSE THERE IS A LOT OF THEM.
Ali builder
Rating: 5 out of 5
Extension Builder in Hertfordshire
Hey I go with the name of Ali builder! I been working in the building field for the last 20 years and have got many clients and every client I work for I make sure I do the 100 percent perfect !
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Latest review:
Mr Muhammad is a great guy with a lot of skills and he was refer to me by friend and he has done my work very nice and on time . Very professional man with great sense of hummer
Home Renovation City Ltd
Rating: 5 out of 5
Extension Builder in Hertfordshire
SKILLS 1 .Plastering 2. Lay Bricks 3. Tiles 4.Renderin 5. Painting decoration 6. Coving 7. Dry Lining 8.Flat Ceilings 9.Renderin 10 Extensions Hello, I am Eneo, proud owner of Home Renovation City Ltd and here’s a little about me: With many happy and returning customers over the last 10 years, you can be sure of being well looked after. My aim is to provide a stress free project, delivered in a manner that I am confident will exceed your expectations. I carry out all work myself and will be your single point of contact. My customers are accustomed with the outstanding quality of my projects, by sourcing quality materials with experienced craftsmanship I create truly bespoke masterpieces lasting my customers many years. Year guarantees are included as standard on all completed work.
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Latest review:
Painting & Decorating- 23 Jul 2022
Eneo painted One bedroom flat in a highly professional manner in a very tight schedule. He was very tidy and provided High quality service. Highly recommended
MGA Projects Ltd
No reviews yet
Extension Builder in Hertfordshire
MGA Projects Ltd is a trusted London-based construction company delivering high-quality building services from start to finish. We specialise in extensions, full refurbishments, loft conversions, and structural works including steel installations. With years of hands-on experience, we pride ourselves on reliability, attention to detail, and clear communication throughout every project. Whether it’s a small renovation or a full-scale build, we work closely with our clients to bring their vision to life—on time and within budget.
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A1
Rating: 4.8 out of 5
Extension Builder in Hertfordshire
Hi i m Gurlal singh We are available 24 hour
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Latest review:
Plumbing- 5 May 2025
On time and great work ethic would truly recommend
Earthmates Construction Limited
Rating: 5 out of 5
Extension Builder in Hertfordshire
Introducing Earthmates: Your trusted partner for all property needs. We offer comprehensive services in new builds, extensions, landscaping, fencing, loft conversions, and complete property management. Whether you’re planning to build from the ground up, expand your existing space, or enhance your outdoor area, Earthmates delivers expert craftsmanship and tailored solutions to transform your property vision into reality. Let us help you create, renovate, and manage with quality and care at every step.
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Latest review:
Landscaping- 20 Sep 2025
Earthmates absolutely transformed my garden. They did an amazing job so I hired them again to redo my driveway. I would definitely recommend them an would hire them again an again. They were a good bunch of guys friendly and professional. If you want a job done right hire Earthmates Construction!
Levismar Formwork & Groundworks Ltd
New on MyBuilder
Extension Builder in Hertfordshire
Levismar Formwork & Groundworks Ltd is an experienced construction contractor with over 25 years of industry experience. We work with homeowners, developers, builders and main contractors on both private and commercial projects. Our services include complete groundworks, excavation, foundations, underpinning, basements, reinforced concrete, formwork, steel fixing, retaining walls, drainage, demolition, structural works, new-build houses, extensions, brickwork, blockwork, roofing, driveways, paving, hard landscaping, external works and site preparation. We can provide complete construction packages or individual specialist services, depending on the requirements of each project. Our team has the workforce, experience and construction plant to support projects ranging from smaller groundwork, driveway and retaining-wall works to major basements, reinforced-concrete structures and new-build developments. We also have excavators from 3 to 22 tonnes, dumpers and HIAB/plant transport, with operated plant available where required. Visit our website to view our services and previous projects. We welcome genuine enquiries from clients looking for reliable, capable and experienced construction support.
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SBM Construction
No reviews yet
Extension Builder in Hertfordshire
Having the heritage of a family business, SBM Construction offers 25 years of experience to Private home owners, Landlords, Developers and main contractors of our services. Fully qualified in our specialist field of brickwork, Masonry and structural applications, we build everything from extensions to garden walls. • Fully insured / Public Liability. • Repairs and Insurance work is welcomed.
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J.Miles Building
No reviews yet
Extension Builder in Hertfordshire
General builder. Level 3 qualified bricklayer. .Extensions .Chimney refurbishments .Guttering .Fascias .Soffits .Driveways .Brick wall repairs .Knock throughs .Roofing
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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.