Extension Builders in Knebworth

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.8 (14 reviews)

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Some of our top rated extension builders in Knebworth

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east herts projects
Rating: 5 out of 5
Extension Builder in Knebworth
We are a small building company, I have 30 years experience as a builder /bricklayer. my main work is extensions and brickwork.
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Latest review:
Repointing- 16 Sep 2024
A great job re pointing the DPC around our bungalow, came when he said he would and had a very pleasant manner and well priced too.
SC DUNCAN CONSTRUCTION LTD
No reviews yet
Extension Builder in Knebworth
SC Duncan Construction provides a general builder service across herts
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Sam plumber
Rating: 5 out of 5
Extension Builder in Knebworth
I'm very good plumber.I'm correct with the customer never have problem back
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Latest review:
Bathroom Fitting- 2 Jun 2026
Amazing work, Sam and his team are dedicated professionals that have real eye for detail. The toilet needed changing position which required a significant amount of rework of pipes. But they made it look easy.. tiling work was done perfectly and Sam helped me find the right products before starting this project. Really happy with the work done and was completed in a timely manner. Highly recommend.
Mevlan & Sons
Rating: 5 out of 5
Extension Builder in Knebworth
Mevlan & Sons is a trusted building company with 10 years of experience in residential construction, specializing in custom homes, renovations, and remodeling projects. With years of experience, we bring a commitment to quality craftsmanship and attention to detail on every job, big or small. Whether you're building your dream home from the ground up or looking to renovate your current space, our dedicated team works closely with you to ensure your vision becomes a reality.
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Latest review:
Good price for complete new bathroom. No issues found when stripping out the old one so they finished on schedule. Came recommended by a friend of a friend kind of thing and glad they were. Got another little job now for them when the weather improves. Good job.
D & F Brickwork
Rating: 5 out of 5
Extension Builder in Knebworth
Brickwork and All ground work,driveway,patio etc...
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Latest review:
Driveways (Paved & Loose)- 20 Dec 2025
Fatos arrived on time and completed the drainage repair efficiently, replacing it with paving bricks and cementing everything off smoothly and neatly. Very professional workmanship and a genuinely nice guy to deal with. Highly recommended.
CVD Constructions
Rating: 5 out of 5
Extension Builder in Knebworth
Hi I'm new as a solo trader with a vast experience in multiple trades I have a team of plumbers and electricians if needed.
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Latest review:
Conversions - General- 8 Oct 2022
Valentin, Dan and Chris did a great job turning an old wooden shed into a beautiful teenage den / home office. They stripped the shed down to the original wooden frame, replaced the roof and cladding, subdivided the internal space into two rooms and a small shower room. The job was reasonably priced though there was a little scope creep much of it due to additions to the original specification that resulted in an increase in price. With hindsight we should have made sure we kept track of additional work. They were friendly, tidy and considerate in the work and the dog loved having them around. They were professional and hardworking and we were pleased with the final result which was excellent value for money. We would recommend Valentin and his team and will have them back to do more work for us.
sb services
Rating: 5 out of 5
Extension Builder in Knebworth
We offer a range of high quality services, Extension, lofts and full or part renovations, plumbing and certified electrical work, we have gas safe engineers for anything gas related, kitchens and top quality carpentry work, bathroom installation and high end tiling, Flooring installation of all varieties (carpets, vinyl, tiles, wood) Whether it’s high end or a rental, we treat all jobs as if they are in our own home
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Latest review:
Kitchen Fitting- 25 Feb 2019
Scott fitted new kitchen, including new units, electrical sockets, new wall and floor tiles. He worked hard, on time, punctual, and on budget.
Redrose construction (Herts) Ltd
No reviews yet
Extension Builder in Knebworth
I am an experienced builder with a passion for providing excellent customer service and high quality work. I have been in the building trade for over 15 years, branching off a successful family building company I have started Red Rose construction. Red Rose Construction specialises in brickwork and covers all areas of general building. We also offer services in the traditional side of the industry ie. Repointing of heritage houses, traditional brickwork, heritage brick cleaning and damp surveying. Red Rose Construction prides themselves on reliability, hard work and attention to detail. All our work is fully insured. Reach out for a chat or quote with one of us, we will be happy to help.
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Fennel Carpentry and Construction
New on MyBuilder
Extension Builder in Knebworth
Hi, I’m George, founder of Fennel Carpentry and Construction. Carpentry is my trade, but my experience goes far beyond that. Over the past three years I’ve worked on new builds, renovations and extensions, developing a strong understanding of multiple trades to deliver high-quality work from start to finish. Before that, I specialised in carpentry and handyman services, taking on everything from hanging doors and fitting door linings to the smaller jobs that make a big difference. I also have over two years’ landscaping experience, which I still enjoy today, and having a plasterer as a dad means I’ve picked up solid plastering skills too. I’m proud to be known for being reliable, honest, hardworking and easy to communicate with. I take pride in every job, no matter the size, and always aim to leave my customers happy. Most of my work is local, but I’m always happy to travel for the right project. If you’re looking for a trusted tradesman, I’d be delighted to help. George Fennel Carpentry and Construction
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WOODLEY RAY LTD
Rating: 5 out of 5
Extension Builder in Knebworth
Woodley Ray was formed early this year by David Ray and Sam Woodley, both expirenced in all forms of construction for over 15 years. Mainly concentrating on domestic extentions, alterations and loft conversions. With already several happy customers happy to provide references. A limited company, VAT registered.
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Latest review:
Committed to delivering great work, and being a successful construction business owner. Strives to grow and get better at what they do there work is excellent. Had work completed both internal and external over a few years would highly recommend Woodley Ray Ltd they are very reliable & extremely professional.
Martini Building & Roofing Ltd
Rating: 5 out of 5
Extension Builder in Knebworth
I do Building and construction since 2010 Quality is our priority
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Latest review:
Tiling- 29 Jun 2022
We needed an experienced and skilled tiler, to fit 800 x 800 glass fronted tiles to a TV wall. The tiles were manufactured to size, and formed one large pattern. Arben did a fantastic job for us, he finished the job in one day, and it was completed to a excellent standard. I highly recommend him!
JLita Construction
Rating: 4.7 out of 5
Extension Builder in Knebworth
J Lita Ltd Building Service is a business established in 2016. We have more than 10 years' experience in providing building services around North London, London, St Albans, Watford, Luton, Amersham, Aylesbury. We specialise in a wide range of services across all aspects of house refurbishment, construction, including house remodels, renovations, extensions, and more, ensuring that we can handle every aspect of your project from start to finish. We provide expert solutions for projects of all sizes. Our team of professionals is highly skilled and dedicated to delivering exceptional results on every project. We have the knowledge and expertise to get the job done right the first time. At J Lita Ltd, we believe that communication is key to the success of any project. That's why we work closely with our clients to understand their needs and provide customized solutions to meet their unique requirements. We are committed to delivering projects on time, within budget, and most importantly to your satisfaction. We look forward to helping you with your projects. Estimates/quotes are available on request, please don't hesitate to give us a call anytime.
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Latest review:
Extensions- 2 Aug 2023
JLita construction were hired after a competitive quote was agreed to carry out work on my kitchen extension project last year. Prompt and dependable Jetmir’s team worked productive long hours with a clear understanding of my wants and requirements. Where it was possible to accommodate they did. Any remedial work was quickly picked up and completed in good time to the required specifications. After completion of work each day, the space was swept and tidied and the space made as usable as possible. I am extremely happy with the work carried out and the attention to detail applied by Jetmir and his team and would, (and have already) happily recommend JLita Construction for any building works. More than satisfied. Many thanks Jetmir and team. Scott
Arlo
No reviews yet
Extension Builder in Knebworth
Our company offer these services: Landscaping Services •Paving •Driveway •Fencing •Grass •Cleaning •Drainage •Garden Repair •Concrete Base •Wooden Pergola
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RV DEVELOPMENTS
Rating: 5 out of 5
Extension Builder in Knebworth
An established and proven family business who have recently partnered with Tf builders to become Thomas Richards. Still working to the highest standards. Specialising in new build developments Extensions and conversions
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Latest review:
Extensions- 1 Jun 2012
Great job. Reliable and high quality work.
Urwin services
No reviews yet
Extension Builder in Knebworth
We are a driveway clearance and demolition specialist, all aspects of clearance and demolition undertaken, competitive rates clean and efficient working in home counties and north London
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Drago construction
Rating: 5 out of 5
Extension Builder in Knebworth
Drago construction started trading in 2023; the company is able to support homeowners with jobs in the following categories: 1- Fencing/Gates 2-Gardening 3-Brickwork
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Latest review:
Fencing- 13 Jul 2026
Excellent job done by Drago . I am so happy with his work . Beautiful pergola and fence . Good quality materials.

3.8

Top rated Extension Builders

Our Extension Builders in Knebworth, are rated 3.8 out of 5 based on 14 reviews from customers like you.

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

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

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

What are the hourly rates of extension builders in Knebworth?

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

Find extension builders in Knebworth with MyBuilder

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

Step 2: Compare different extension builders in Knebworth

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

Step 3: Hire Knebworth extension builders with confidence

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

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

What to ask a Knebworth extension builder before hiring?

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

An extension builder in Knebworth 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 Knebworth 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 Knebworth?

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 Knebworth 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 Knebworth 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 Knebworth

Can an extension builder in Knebworth help with planning permission?

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

Many Knebworth 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 Knebworth help with materials and finishes?

Yes, most extension builders in Knebworth 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.