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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Raf Building Services
No reviews yet
Extension Builder in Hertfordshire
Fully qualified carpenter, NVQ3 , insured and happy to help.. No job to small or to big - from flat pack furniture to complete loft covertion.
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Gabriel Slavik
No reviews yet
Extension Builder in Hertfordshire
I’m doing building work for last last 23 years. I always try to do precise work, I am happy to help and advise the customer.
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landcraft improvements
Rating: 5 out of 5
Extension Builder in Hertfordshire
Hi John here. Thank you for viewing my profile. I have been in the family business of landscaping and roofing construction work for many years gaining lots of experience form many types of projects. I offer competitive rates and aim to offer professional advice and carry out work to a high standard. Thank you again John.
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Latest review:
Roofing (Pitched)- 5 Mar 2024
John, an all round great person to deal with. Very helpful and did an excellent job. Would def recommend. :)
365 BUILDING LTD
Rating: 5 out of 5
Extension Builder in Hertfordshire
At 365 Building, we focus on quality over quantity. With many years of experience across a wide range of construction and carpentry projects, we take pride in delivering work that is done to a high standard, completed on time, and kept clean and tidy throughout. What We Do We offer a full range of building services, including: • Carpentry & woodwork • Kitchens & renovations • Flooring & doors • Roofing • Extensions • General building and property improvements We approach every project with care, precision, and professionalism—whether it’s a small repair or a full home improvement. Why Customers Trust Us Our customers appreciate our attention to detail, respectful working style, and strong workmanship. We aim to make every client happy, and many of our projects come through recommendations from homeowners who value the quality of our work.
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Latest review:
Hard Flooring- 23 Jan 2026
Great and honest work, very quick and flexible. Would 100% recomend
Star 5 construction ltd
Rating: 5 out of 5
Extension Builder in Hertfordshire
Hi everyone,Star 5 construction Ltd provides best quality of work with affordable price and finish your project with in giving time. For coustmer satisfaction we will provide you our liability insurance details. Our services: New build Extension. New loft conversation and new Roofing. Supply and fit new double glazed windows and doors, with K silicone rendering or Standard plastering. All types interior and exterior design and build. All types supplied and install steel beams. Free quotes and estimate. Many more offers if you need any information feel free to send us email with your plan, happy to provide you all the information.
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Latest review:
Mr singh and his team have done an excellent job,couldn’t have been more happier.Mr Singh’s experience and advice has saved me some serious money.really happy with the final product. It was big and complex task but it was completed in very efficient and professional manner.without any hesitation I’ll be recommending their services to friends and family
Core Design and Build Ltd
No reviews yet
Extension Builder in Hertfordshire
I'm Callum from Core Design and Build Ltd we are based in Hertfordshire, specialising in residential refurbishments, loft conversions, extensions and new builds. We have over 40 years of experience in the construction industry. Our team is made up of a professional team that completes every project to a very high standard.
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Garnet Construction Ltd
Rating: 4 out of 5
Extension Builder in Hertfordshire
Garnet Construction has over 10 years' experience in the industry and specialise in loft conversions, all types of extensions and complete renovations. Priority is given to the design and construction of all our projects with a unique obsession to strive for perfection.
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Latest review:
Extensions- 18 Sep 2019
To start off with the job went reasonably well - we were happy with the workers and the progress. but when we neared completion the work slowed up we waited 3 months for a response from Jordan. we had an issue where his plasterer hid the plumbing access in the wall. - This cost us £500 to sort and re-decorate so we came to an agreement that this was fine and at the time i presumed that Jordan was going to sort out the building control. so we then chased and chased but obviously since he had his money he wasn't interested he answered the phone and hung up. so we called building control and there are 2 small bits to fix which are all due to his work not being up to scratch. obviously i will be paying out for this - so please be careful when using him and dont pay him until you have all of the documents as he will not resolve any issues after being paid. i have had 2 previous building projects and this was by far the worst experience going. avoid dont use him thanks
LondoNest Ltd
Rating: 5 out of 5
Extension Builder in Hertfordshire
Londonest is a London-based building company specialising in high-quality residential construction and renovation. We provide reliable and professional services including house extensions, loft conversions, full property refurbishments, kitchen and bathroom renovations, and general building works. Our team combines strong technical expertise with attention to detail to deliver projects that meet the highest standards of quality and safety. We work closely with our clients from the initial consultation through to completion to ensure every project is delivered on time, within budget, and to the client’s satisfaction. At Londonest, we pride ourselves on clear communication, transparency, and a commitment to excellent workmanship.
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Latest review:
We hired this builder for a 2-metre rear extension and a very large garage extension and we’re really happy with the result. The project needed a pile foundation which is a bit more complicated, but they handled everything very professionally. They listened to what we wanted and kept us informed at every stage, which really helped as we were living in the house while the work was being done. The team were friendly, easy to deal with and worked to a good standard. Overall a very good experience and we would happily recommend them.
M B WARNER GENERAL BUILDERS
No reviews yet
Extension Builder in Hertfordshire
City and guilds qualified in Bricklaying With over 19 years experience. Extensions, bricklaying, alterations, plastering, fencing, patios and general building work.
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AK Bespoke carpentry & construction
No reviews yet
Extension Builder in Hertfordshire
I’m a qualified carpenter with a background carrying out extensions, loft conversions and new build carpentry packages. I’m new to MyBuilder, as I’ve only just recently formed my company. This decision was made having been project managing and supervising on extensions, loft conversions and renovation work for a Building company since 2015. Please don’t be alarmed that I have no feedback as yet, photos of my work clearly demonstrate that the sky really is the limit.
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Lcd
Rating: 1 out of 5
Extension Builder in Hertfordshire
Hy I am cris more 15 years experience in carpentry and building work
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Latest review:
Joinery & Cabinet Making- 8 Jan 2024
Absolute cow boy 🤬 Don’t even think of hiring So many faults Door not closing Plinth boards cut wrong So much more disgrace
Florin Stancu
No reviews yet
Extension Builder in Hertfordshire
My business consists in undertaking various aspects of construction and building. I’ve been in the business for about 15 years doing both site and private work. The type of work that I usually do is: - extensions - bricklaying - refurbishment
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Medi Building and Construction
No reviews yet
Extension Builder in Hertfordshire
As I need to improve my Mybuilder feedback, I would not worry about the price of your job. So it is a great opportunity for you to get your work done in the best possible way and minimum price. Although we are new in Mybuilder, we are professional and qualified team in many construction aspects with over 20 years experience. We want to make sure that you get what you want at the highest standard and minimum price. Please don't hesitate to contact me for any reason. Many thanks Mehdi
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P O'Brien Builders London LTD
No reviews yet
Extension Builder in Hertfordshire
P O’Brien Builders is a trusted, family-run building company with decades of experience delivering high-quality construction services across London. We specialise in home renovations, extensions, loft conversions, and new builds, offering a reliable and professional service from start to finish. Our reputation is built on quality workmanship, attention to detail, and clear communication throughout every project. Whether it’s a small upgrade or a full renovation, we approach every job with the same level of care and commitment, ensuring results that are built to last. As a family business, we take pride in what we do. With the next generation now involved, we combine traditional values with a modern approach to building, giving our clients confidence in both the process and the final result.
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d&d building & property maintenance
No reviews yet
Extension Builder in Hertfordshire
We are a general building and property maintenance company that builds houses, extentions ,loft conversions and undertakes any house hold referbishments .Our company also provides commercial building works for various schools local to us who will be happy to provide references. With over 25 years years experience our aim is to make sure the customer is always satisfied.
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Nc property services
Rating: 5 out of 5
Extension Builder in Hertfordshire
Fully qualified electrician and multi-trade specialist with over 20 years of hands-on experience delivering single-storey extension builds, complete kitchen and bathroom refurbishments, and commercial refits. Based in Loughton, I serve clients across London and the Home Counties. Experience Over 13 years of trade experience spanning domestic extension builds, structural wall modifications, full kitchen and bathroom transformations, and co-founding a 39-strong engineering firm. Services & Expertise Extensions & Structural Builds: Single-storey extension framing, structural wall openings, carpentry, and flat roof repairs/installations. Kitchen & Bathroom Refurbishments: End-to-end fit-outs, floor laying, plumbing, electrical integrations, and space layout modifications. Electrical Compliance: CSCS card holder with Inspection & Testing certification for rewires, fault finding, testing, and consumer units. Maintenance & Repair: Planned preventive maintenance, disrepair remediations, and general trade upgrades. Areas Covered Loughton (IG10), Greater London, Essex, and surrounding Home Counties. Why Choose Me I offer direct, approachable communication and strict attention to detail on every project. From structural extensi
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Latest review:
Nick is excellent. Very resourceful and has a great attention to detail. He's given us the confidence to do more work to our house. Would highly 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.