Extension Builders in Knebworth

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.6 (12 reviews)

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Some of our top rated extension builders in Knebworth

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Wolfwood Homes Ltd
No reviews yet
Extension Builder in Knebworth
I run a construction company that provides a services to both domestic and commercial clients. Our services range from initial site surveys including conditional surveys of existing properties, detailed design for both planning and building regulations, project management or main contractor service. We currently run projects that range from loft conversions and extensions through to completed builds, while at all times being customer focused with quality and safety as our priority.
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Gazmend
No reviews yet
Extension Builder in Knebworth
Hi my name is Gaz, I do extensions from start to finish, loft conversion, Garden refurbishment and patio, Best prices around guaranteed Don’t hesitate to give me a call
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Florin Pascu
Rating: 5 out of 5
Extension Builder in Knebworth
Hello, I'm florin and welcome to my profile! I've been working in construction and building for the past 15 years, and have made all my customers happy, completing work to a high standard very efficiently. I'm available to talk anytime if you are interested to take a hard working person like me. Don't hesitate to contact!
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Latest review:
Plastering- 9 Jul 2026
Florin is an experienced professional who is multi skilled with range of different materials and trades. He is very trustworthy and was tidy and organised throughout. He had good communication and was committed to the project and finishing on time. Like all projects unexpecting things crop up however he worked with us to finish at a very high standard. We love our new warm house and cant thank Florin enough. I have had issues with builders in the past but this project was a dream. He listened to our requirements and used quality products, no corners were cut. 5 stars!
Dizzain Ltd
Rating: 5 out of 5
Extension Builder in Knebworth
The multi trader with excellent skills and consistently good in work performance. If you need help with your house project, such as internal structural changes, rear extensions, loft conversions or any other house structural issues, please don't hesitate to contact. Happy to help and discuss suitable solutions regarding structural design, and to comply with building regulations. A fair and good fees.
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Latest review:
We used Andrius recently and were very happy with the service. Inspected our house and spent a lot of time discussing everything in detail. He completed the drawings very quick and communication was good. Good value for money. He even helped amending something later on as needed. Thank you!
Femtec Heating Services
No reviews yet
Extension Builder in Knebworth
I take on any type of heating jobs small or big Any type of plumbing we can fit new bathrooms plum washing machines and dish washers.At a very reasonable price.we also take on house refurbishment (Any typ)
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Hasanozdemir
No reviews yet
Extension Builder in Knebworth
I have been working in the construction industry for 7 years, and I do painting, repair, parquet ,laminate flooring, partitions, loft construction, garden works, pavement, digging, demolition, fencing etc.
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Comer Construction Services
No reviews yet
Extension Builder in Knebworth
I am a multi skilled builder, I set up Comer Construction Services 10 years ago and before that worked in my father's construction company for 10 years. I will take on work of all sizes from an extension that takes 18 months to fitting a laminate floor that is put down in a day.
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HEXAFORM CONSTRUCTION LIMITED
Rating: 5 out of 5
Extension Builder in Knebworth
HEXAFORM is a London based multi-disciplinary design and build company that has the experience, work ethic, communication tools, and systems in place needed to bring any scale project from a virtual blueprint to reality. Historically the architect-contractor relationship has been one of an ‘us versus them’ mentality. But we’re 'both'. Having a design team under the same roof as a construction company means that the eccentricities of each project are rendered opportunities, rather than obstacles.
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Latest review:
Architecture- 12 Jun 2023
Lots of ideas, step by step explained. Easy to work with. Highly recommend
ARJD BRICKWORKS LTD
New on MyBuilder
Extension Builder in Knebworth
Trusted & Skilled Bricklayer I provide bricklaying, masonry, wall building and repair services. All work is safe, accurate and finished on time. I offer reasonable rates and guarantee my work. I am based in Bedfordshire and ready to help with your project.
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B&K
Rating: 5 out of 5
Extension Builder in Knebworth
B.K. Building & Renovation is a family-run building and renovation business based in South Harrow. We provide reliable, high-quality work across extensions, brickwork, blockwork, plastering, painting and decorating, tiling, flooring and general property improvements. We take pride in clean workmanship, clear communication and attention to detail from start to finish. Whether it is an internal renovation, plastering and finishing work, brickwork, flooring or a larger building project, we aim to complete every job safely, neatly and to a professional standard. Customers choose us for our reliable service, respectful approach, tidy working habits and commitment to quality. We treat every property with care and work hard to deliver results our customers are happy to recommend.
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Latest review:
Benjamin and his team did a fantastic job on my property building a 6m by 6m Extension walls in only 2 days, it was done ahead of time and on budget. He was very conscientious and nothing was to much trouble. Done all the pictures of each step along the way needed for Building Control Guy. The quality and workmanship was first class and I would definitely recommend him for all types of building/refurbishment work.”
Lcd
Rating: 1 out of 5
Extension Builder in Knebworth
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
Powerbiz ltd
Rating: 4.2 out of 5
Extension Builder in Knebworth
Hi, We are a LOFT conversion and EXTENSION specialists to look after the construction side of the building works. Over 20 yrs of experience and accumulated variety of different skills. We take pride in our teamwork and always keep costumers interest on high priority . On qualification side I am a GAS SAFE registered and undertake works like New boilers , central heating and underfloor heating, also a REFCOM registered air-conditioning installer Many thanks and hope to hear from you soon.
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Latest review:
Extremely professional and great attention to detail. Very approachable and committed. The job carried out was of very high quality and neat. Complete transformation of my Living Room.
Alex
Rating: 5 out of 5
Extension Builder in Knebworth
Hi I offer good quality work which includes general construction works, painting interior, exterior, walls and ceiling repair and wood work I also offer handy man jobs, decking installation and repair,groundwork jobs.
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Latest review:
Painting & Decorating- 6 Jul 2026
Excellent communication and decorating done to a high standard. The rooms look beautiful and Alex was very clear about what needed to be done at all stages. When bits of the job changed, he revised the bill down in keeping with the fact less work was needed.
Rumahn International
No reviews yet
Extension Builder in Knebworth
With over 35 years of experience in the building industry, we offer a complete A–Z service across all trades — from builders, carpenters, fitters, and bricklayers to electricians, plumbers, and more. Whether it’s a minor repair or a major development project, we provide trusted professionals for every job. At Mazmo, we pride ourselves on delivering exceptional service, reliability, and peace of mind. Our “one-stop shop” approach means you don’t need to look elsewhere — we handle everything under one roof. Quality workmanship. Proven expertise. All in one place.
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BORUFI BUILDRES
No reviews yet
Extension Builder in Knebworth
NEW BUILDS LOFT CONVERSIONS EXTENSIONS FULL REFURB
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Absolute Drylining ltd
No reviews yet
Extension Builder in Knebworth
Hello My name is Luke Jell and I am the Managing Director of Absolute Drylining ltd. I have been project managing in main construction for the last 10 years. I Have managed large jobs up to £5m with 150 flats and I have managed multiple jobs at any one time, During my journey I have managed all trades internal and external and have a large amount of experience in building and I also do extensions and full house refurbs. I have a calming nature and take pride in my work.
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3.6

Top rated Extension Builders

Our Extension Builders in Knebworth, are rated 3.6 out of 5 based on 12 reviews from customers like you.

Quality screening

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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.