Extension Builders in Knebworth

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.9 (15 reviews)

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Some of our top rated extension builders in Knebworth

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Keystone Building and Renovation Ltd
Rating: 5 out of 5
Extension Builder in Knebworth
We build, create and renovate homes:- Kitchen refurbs Bathroom refurbs Building works Extensions
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Latest review:
I got a good feeling as soon as I met Darren from Keystone. Sometimes, I find builders and tradespeople difficult to talk to but Darren was super friendly and chatty, as we went through my plans. Darren's input was really helpful and he and his team got the work done quickly and efficiently; also couldn't believe how tidy they were, thought there was going to be mess everywhere! Amazing job, at a really good price and great communication throughout...can't recommend highly enough.
OWA CONSTRUCTION LTD
Rating: 4.9 out of 5
Extension Builder in Knebworth
We are a medium sized groundwork company based in West London. We have over 18 years groundwork experience. We specialise in Drainage , Basements Reinforced concrete, Foundations, Block and beam , Paving , Fencing Etc . We pride ourselves in our work and customer satisfaction is our top priority.
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Latest review:
Groundwork & Foundations- 7 Feb 2026
Oli carried out the groundworks and demolition at my property and was on site every day with his crew, fully committed and hands-on throughout the job. I am an architect, and this was work on my own home, so my expectations were high. Oli met those expectations fully. He has a strong knowledge of groundworks and demolition, works carefully and methodically, and you can tell he genuinely enjoys what he does and takes real satisfaction in delivering the work exactly as required. He was always in a good mood, easy to communicate with, and a pleasure to have on site. I enjoyed discussing the project and hearing about other jobs he has completed over his 23 years of experience, which clearly shows in the quality of his work. I would highly recommend Oli for any groundworks or demolition works.
WARREN LESTER - BUILDING AND MAINTENANCE
No reviews yet
Extension Builder in Knebworth
Bricklayer of 6 years now, working with a number of firms on price. both on and off site also taking on my own jobs such as extensions, new builds and garden walls. first time using MyBuilder.com but DO have hand written references and photos to confirm quality and proof of work.
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Amazing constructions limited
Rating: 5 out of 5
Extension Builder in Knebworth
we are specialised-Loft conversion, Extension, Brick work, Plumbing, Electric, Roofing, Bathroom, Tiling, kitchen, Flooring, Paint, and have experience of 15 years.
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Latest review:
Extensions- 10 May 2021
Very Professional and diligent service, even though was hard to get materials because the job was done at the peak of the pandemic, still they managed to sort things out. The job was so nicely done that all the tenant who viewed the house wanted to rent it. I have even given them another job would certainly recommend.
Friesian Group Ltd
No reviews yet
Extension Builder in Knebworth
We are a reliable construction and refurbishment company specialising in bathroom and washroom renovations, as well as all types of home repairs and refurbishment work. Our team delivers high-quality workmanship, attention to detail, and a professional service from start to finish. Whether you need a full washroom makeover or small repairs around your home, we are here to provide fast, trustworthy, and affordable solutions.
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Ionut
Rating: 5 out of 5
Extension Builder in Knebworth
Hello, I'm Ionut handyman, I also do tile and floor work, as well as paving and driveway work.
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Latest review:
Landscaping- 7 May 2026
“We recently had our landscaping redone along with new turf installation, and the results were excellent. The team was professional, punctual, and paid great attention to detail from start to finish. They completely transformed the garden, leaving everything neat, tidy, and looking amazing. The new turf was laid perfectly and has already made such a difference to the overall appearance of the space. Communication throughout the project was clear and friendly, and the workmanship was top quality. Highly recommend to anyone looking for reliable and skilled landscapers.”
Euro Elite Projects Ltd
No reviews yet
Extension Builder in Knebworth
We are Euro Elite Projects, a London-based construction company established in 2024, we stand out for our experience, expertise, and commitment to excellence. Our seasoned team of contractors, with over 20 years in the industry, brings unparalleled skill to every project. From quality craftsmanship to great customer reviews, we prioritize attention to detail and fresh perspectives. Trust us as your partner in building dreams.Choose us for top-tier construction services that turn your vision into reality! Always here for you! Euro Elite Projects
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Elvis Torba
No reviews yet
Extension Builder in Knebworth
Hi, I’m Elvis, a professional bricklayer with over a decade of experience in all aspects of brickwork and masonry. I take pride in delivering high-quality workmanship, whether it’s garden walls, extensions, repointing, repairs, patios, or new builds. I’m reliable, hardworking, and always make sure every job is completed to a high standard with attention to detail. Customer satisfaction is very important to me, and I always aim to keep work areas tidy, finish on time, and provide honest, competitive pricing. I cover local surrounding areas and am happy to take on both small repairs and larger projects. If you’re looking for a trustworthy bricklayer who takes pride in their work, I’d be happy to help.
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CJ Carpentry
Rating: 5 out of 5
Extension Builder in Knebworth
We are joiners by trade, passionate on what we do over the years. We have combined over 32 years of experience on carpentry/joinery itself. As there is always demand, we started delivering any type of construction work, full house refurbishment, kitchens, bathrooms etc. Always preserving our high quality of work, honesty, professionalism. Fully committed to anything we can come across, always find clients, architects solutions so we can achieve everyone’s dream, expectations.
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Latest review:
Carpentry- 18 May 2022
Very professional and friendly tradesman. Work was carried out perfectly and I couldn't recommend him high enough. Brilliant work ethic and he went the extra mile to carry out the works impeccably. Privellage to work with him.
Guri*s Brothers
No reviews yet
Extension Builder in Knebworth
Landscaping,gardens,paving,maintenance
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K vision developments ltd
No reviews yet
Extension Builder in Knebworth
With over five years of hands-on experience across multiple trades, I provide reliable, high-quality workmanship for homes and businesses. I’m a fully trained locksmith, builder, extension builder, and plumber, offering a wide range of services from small repairs to large-scale property improvements. I specialise in emergency callout maintenance, delivering fast, efficient solutions when you need them most—whether it’s a locked door, a burst pipe, or urgent structural repairs. My approach is built on professionalism, clear communication, and a commitment to getting the job done right the first time. No matter the size of the project, I take pride in offering dependable service, honest advice, and craftsmanship you can trust.
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Dk construction
No reviews yet
Extension Builder in Knebworth
Very friendly and trustworthy i love my job and i always deliver a high standard jobs. Been on this trade for over 25 years and very skilled
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Lubjana meshi
New on MyBuilder
Extension Builder in Knebworth
BK Construction provides reliable, professional and high-quality building services for homeowners and businesses across London and surrounding areas. We specialise in extensions, loft conversions, renovations, refurbishments, waste clearance and general building works. We take pride in delivering quality workmanship with attention to detail on every project, whether it’s a small improvement or a complete property transformation. We understand that building work is a major investment, so we focus on clear communication, honest pricing and keeping our customers informed from start to finish. Our team works efficiently, safely and respectfully, treating every property as if it were our own. We aim to make the entire process as straightforward and stress-free as possible while delivering results that meet our customers’ expectations. Choose BK Construction for a reliable service, quality workmanship and a professional approach. Contact us today for a free quotation and let us help bring your building project to life.
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NA Builders Ltd
No reviews yet
Extension Builder in Knebworth
NA Builders LTD is a reliable and professional building company providing high-quality construction and renovation services. We take pride in delivering excellent workmanship, clear communication, and projects completed on time and within budget. With strong experience in the building trade, we specialise in a wide range of services including extensions, renovations, structural work, brickwork, plastering, and general building projects. No job is too big or too small – we give every project the same level of care and attention to detail. Customer satisfaction is at the heart of what we do. We work closely with our clients to understand their needs, offer honest advice, and ensure the finished result meets their expectations. Our team is hardworking, respectful, and committed to keeping sites clean and safe at all times. If you are looking for a trustworthy builder who values quality, reliability, and professionalism, NA Builders LTD is here to help.
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City Building and Roofing Ltd
Rating: 4.9 out of 5
Extension Builder in Knebworth
City Building and Roofing Ltd provides professional roofing, refurbishment and building services across London and Surrey. Our services include roof repairs, new roofs, flat roofing, GRP roofing, roof refurbishment, guttering, fascias and soffits, chimney work, damp proofing, brickwork and full property refurbishment. We work with homeowners, landlords and commercial clients, delivering reliable workmanship, honest advice and free no obligation quotes.
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Latest review:
Damp Proofing- 26 Mar 2022
Good,timely and clean workers. Worked hard and efficiently with clear explanations. Very satisfied with the finish.
Bull&Chisel
Rating: 5 out of 5
Extension Builder in Knebworth
We are an experienced business focusing on all building, renovations, kitchen and bathroom fitting as well as painting. Feel free to view our web page and request a free quote.
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Latest review:
I was planning an extension to my kitchen, which included a complete refurbishment and the addition of a shower room. I also needed somebody to coordinate all aspects of the project, including recruiting the right resources for the building work, electrics etc. I was extremely pleased that Bull & Chisel were recommended to me. From the start, Bryan and Warren gave me the confidence that they were able to complete the project to my satisfaction. They were happy to continue working with me throughout and they liaised effectively with partners they brought in at key stages to ensure that each task was completed to my satisfaction. As for their own work, I cannot fault them. There are always unexpected challenges that arise in these types of project. Bryan & Warren consider these very carefully before providing a solution. They pay close attention to detail and that has resulted for me in a super new space. I highly recommend Bull & Chisel and have already asked them to sign up for more projects in the near future!

3.9

Top rated Extension Builders

Our Extension Builders in Knebworth, are rated 3.9 out of 5 based on 15 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.