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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JHF Construction Limited
Rating: 5 out of 5
Extension Builder in Knebworth
JHF Construction Ltd have been established as a limited and VAT registered company since March 2018. Located on the outskirts of Hitchin, our brand-new Studio is an example of our work and welcomes visits. We provide a reliable, professional service with innovative concepts and pride ourselves on the quality of our work. We offer everything from design through to completion and work hand-in-hand with our clients to ensure expectations are met and exceeded. Always striving to go the extra mile.
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Latest review:
Kitchen Fitting- 27 Feb 2019
Jack and the team did a great job on our new kitchen including new electrics, tiles and underfloor heating and we’re truly delighted with the end result. Jack was always available to discuss the project and answer any questions or concerns I had and was able to quickly overcome issues we experienced relating to the kitchen units and a design error. He was always professional and gave us useful tips and input into the overall kitchen design and helped us source very nice materials. As with many small businesses, Jack and the team were juggling other jobs along side ours which meant that after some unexpected additional work on our floor, they were unable to complete the job within the original timeframe plus 2 days contingency. As a family with young children we found this really difficult so I would urge you to project manage closely. It was all totally worth it in the end though and overall I would recommend Jack and the team.
ERIC GROUP LTD
Rating: 5 out of 5
Extension Builder in Knebworth
Eric Group Ltd has been trading for over 10 years and has completed numerous refurbishment and fit-out projects. We offer free survey and estimates and free specialist advice. If you want a new kitchen, a new bathroom, a house extension or a full house refurb, get in touch for a chat.
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Latest review:
The Job was to extend the rear of the house on the ground floor, open up the kitchen and reception room into one open plan living area, to refresh the rest of the house which included new plaster skim, doors and frames and to fit new bathrooms and kitchen as well as an rewire on the whole house and the construction of a retaining wall in the garden to accommodate the extension. Florins team were excellent from start to finish, the whole project was completed in record time to a very high standard. The 10 weeks turnaround was incredible, we were very happy that Florin was always here at the property or on the end of the phone throughout the process, his professional advice and smart ideas made for a smooth transition from room to room. The team were very hard working, polite and knowledgeable, these guys worked very hard and very quickly which was amazing to see and I was very grateful we were able to move into the property earlier than planned which even saved us money on the temporary accommodation we had! Can’t thank you enough Florin, any small issues we had were dealt with quickly and smoothly, I love the house, the level of work and would 100% use Florin and his team on my next project!
Gary prime
Rating: 4.5 out of 5
Extension Builder in Knebworth
I have been actively involved in the construction industry for the past seven years, during this time I have gained experience in ground works, bricklaying and a variety of other trades and in the last two years I have been working in a supervisory role. I have worked on large construction sites as well as carrying out works on property refurbishments.
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Latest review:
Groundwork & Foundations- 14 Aug 2019
Gary did an excellent job on the drainage, everything I asked of him. He was punctual and polite, wouldn't hesitate to hire him again.
TJD Driveways & Landscape
No reviews yet
Extension Builder in Knebworth
My name is Tony. I'm a qualified bricklayer who has experience in New builds, extensions, footings, groundworks. I also specialise in driveways, patios and all aspects of landscapeing . I've always been tought to do the job right first time. I'm proud to say i produce exceptional work and standards. Clarified by every customer and building official I've worked with.
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N M Building and Roofing Ltd
Rating: 5 out of 5
Extension Builder in Knebworth
Hi we are n.m building and roofing we are a family business that undertake all building / roofing / and / landscaping work all our quotes are free and all work is guaranteed we have many 5 star testimonials for our work we have been working with many happy customers for over 20 years we look forward to hearing from you many thanks Neil N.M building we are also a 5 star approved with trust a trader
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Latest review:
Landscaping- 12 Aug 2024
Neil provided a professional assessment of the job, quoted and carried out the work in a honest and professional manner. Good job tidied up a and provided good advice after the work was completed. I would recommend N M Building and Roofing Ltd
A and B Gardening LTD
Rating: 5 out of 5
Extension Builder in Knebworth
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:
Hard Flooring- 1 Sep 2026
Absolutely brilliant guys fantastic job doing my floors they had a problem putting it down as I left the packs out side and the wood swelled from the rain but the managed to lay it after hours of trying. Thanks Dan and partner brilliant job done
D Bird carpentry and building LTD
Rating: 5 out of 5
Extension Builder in Knebworth
Hi were Dbird Carpentry & Building we are a family run company by myself Daniel and my brother Ellis. We take pride and love what we do! We will help you every step of the way through your project no matter the size.
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Latest review:
Conversions - General- 21 Jun 2022
D Bird Carpentry completed the works on time and to a high standard. Dan and his team were a pleasure to work with and I would be happy to work with them again.
Century21 lofts and extensions Ltd
Rating: 5 out of 5
Extension Builder in Knebworth
Century21 lofts and extensions Ltd are a residential design and build company that offers the personal touch.the company was founded on the idea of providing quality workmanship working alongside our clients, to ensure we deliver an excellent service and building solution tailored to your requirements. We provide expertise and experience in full house renovations, loft conversions and single & double storey extensions. We provide comprehensive, no obligation, quotes and are more
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Latest review:
Carpentry- 12 Jun 2025
Replaced roof, doors and windows for a small lean too. Work completed in 2 days. Shev was very professional and so was the others. Very pleased with the job. Thank you!
Enzo Build Solutions Ltd
Rating: 5 out of 5
Extension Builder in Knebworth
Enzo Build Solutions Ltd is a reliable, family-run building company providing high-quality workmanship across all aspects of construction and property improvements. We specialise in renovations, extensions, kitchens, bathrooms, carpentry, plumbing, electrical work, painting & decorating, and general maintenance. We take pride in delivering honest, professional service with attention to detail from start to finish. Customer satisfaction is our priority, and we aim to complete every project on time, on budget, and to the highest standard. No job is too big or small
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Latest review:
Had a very beautiful bathroom done to a very high standard, would highly recommend
Phi Architectural Services Ltd.
Rating: 5 out of 5
Extension Builder in Knebworth
Phi Architectural Services Ltd. specializes in providing architectural, structural and project management services from small to big sized residential projects. With more than 12 years of experience and more than 500 projects ranging from refurbishment to new build houses and flats, the firm also have its own team of sub-consultants and contractors.
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Latest review:
CAD / Drawings- 6 Mar 2022
Very helpful architect. Needed a little nudge occasionally due to busy season, but the work is delivered in time and to a high standard. I'm happy with the result.
Adi
Rating: 5 out of 5
Extension Builder in Knebworth
Hi, I'm a bricklayer living in Luton I'm part of a team of bricklayers, we can work for you if you wish it . We did already a lot's of extenshions and houses in differents sites .
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Paternoster building services limited
No reviews yet
Extension Builder in Knebworth
With 20 years of experience in the building industry, I have successfully managed a wide range of projects, from small-scale bathroom renovations to large, complex refurbishments and extensions, including bespoke features such as saunas, steam rooms, gyms, and frameless glass balconies. I began my career mastering the wet trades, groundwork, and drainage, before transitioning to a role with a company that allowed me to broaden my expertise across all areas of plumbing. Over time, I specialized in bathroom fitting, honing my skills in high-quality bespoke installations and design. Upon founding my own company, I chose to focus on property development and extensions, driven by a passion for witnessing the complete transformation of properties. This experience has enabled me to deliver exceptional results and exceed client expectations on every project.
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L R Harvey (Builders) Ltd
Rating: 5 out of 5
Extension Builder in Knebworth
I am a local builder with 35 years experience in the trade. I am reliable and trustworthy with a reputation for being clean & tidy. I specialise in brickwork, hard landscaping, extensions from start to finish & internal alterations. I work closely with all my clients to ensure that they are pleased with the results.
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Latest review:
Groundwork & Foundations- 5 Mar 2021
Very professional and all round lovely person punctual, professional and honest Would highly recommend L R Harvey builders, don’t hesitate give him a call.
Brandon’s building
No reviews yet
Extension Builder in Knebworth
Hi my name Brandon I’m a 22 year old builder from St Albans. I’m a bricklayer by trade but can do all building jobs like ( drive ways , patios , garden walls , landscaping ,clearance ext) I’m looking to expand my business and customers so if you need anything doing as little as they are just get in contact. Thanks
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D H S HOUSING LTD
No reviews yet
Extension Builder in Knebworth
Hi my name is David I run this business in which I work a long side other, we are a very hard working team that bring out the best quailly in whatever we do to improve home and to fulfil our customers needed in there home improvement I take great proide in my job and commitments in everthing I do
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NESIMI CONSTRUCTION LTD
Rating: 5 out of 5
Extension Builder in Knebworth
Nesimi construction ltd With over 18 years of experience, we specialise in bricklaying, driveways, and paving. We carry out all types of work including garden walls, patios, extensions, repairs, and general building. We pride ourselves on high-quality workmanship, reliability, and attention to detail. All jobs are completed to a high standard, on time, and at competitive prices. Friendly, honest, and professional service from start to finish.
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Latest review:
When Mr Nesimi came to undertake a pre-assessment for my front wall, he came across very professional and genuine and very honest about the work needed doing. He even suggested some changes to the work to reduce cost. The quote he gave me for the job was very reasonable and he was able to slot in my job within a week and arrive sharp on time at 8am and got on to the job straight away as I had a busy day at work for me to attend to. I notice that right from the start he was very clean and meticulous with the work and his job was of a very high quality ( compared to a job I had done by another builder 9 months ago). My neighbours also noticed this difference and were praising Mr Nesimi’s work. I would definitely recommend Mr Nesimi for any construction work as I felt he was very professional, reliable and honest and most of all the work was of high quality. I will be certainly calling him for my next job, most likely the driveway resurfacing and the attic conversion within the next year.

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.