Extension Builders in Welwyn Garden City

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 Welwyn Garden City

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Ali builder
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Hey I go with the name of Ali builder! I been working in the building field for the last 20 years and have got many clients and every client I work for I make sure I do the 100 percent perfect !
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Latest review:
Mr Muhammad is a great guy with a lot of skills and he was refer to me by friend and he has done my work very nice and on time . Very professional man with great sense of hummer
Electrical
No reviews yet
Extension Builder in Welwyn Garden City
Electrical work
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Brickwork
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Deep Brickwork provide professional bricklaying services. We doing all types of brick/block work and complete water tight shell including digging, poring concrete, roof work and internal work as well. If you looking for someone to do New build houses, extensions,Outbuild, garages any type of work Feel free to contact us.
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Latest review:
Bricklaying- 1 May 2026
I needed a shed done and Ranjit and the team provided a competitive quote and explained everything they would do. They arrived on time for all meetings and when the work started, worked solid every day, completing the work in good time. Shed was built to a good standard and the quality of work was very good. They tried to keep things clean and tidy and once finished left the garden clean of rubble. I would definitely recommend them to anyone looking to build a shed or similar.
Onyx Construct Limited
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are a multi-trade construction company operated in domestic sector and we are able to full-fill any building requirement. The scope of projects we have delivered in the past spans from smallest jobs like kitchen or bathroom fitting to extensions, house refurbishments or loft conversions.The majority of our previous clients were extremely satisfied with high standard and quality of work. If you are looking for professionals builders with reasonable prices - you are on the right profile !
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Latest review:
Extensions- 29 Nov 2023
We had the most fantastic experience with Sarunas. He was highly professional from start to finish and completed the work to the highest standard. We extended our project significantly once we realised how excellent he was and he has now renovated our whole home over an 18 month period. He was able to guide us through the process and help us make key decisions which made the experience smooth and efficient. He is extremely skilled in all aspects of building, has high attention to detail and is a pleasure to have in your home! I couldn't recommend him higher and look forward to having him back in future to convert our loft!
Craft Construction Ltd
No reviews yet
Extension Builder in Welwyn Garden City
Craft Construction have been running since 2011 and have worked on many large projects from full refurbs to removing complete roofs and replacing with new we can provide photographic evidence of completed works.
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Mprgroundworksltd
No reviews yet
Extension Builder in Welwyn Garden City
Hi my names is michael from MPR groundworks we are a groundwork company that can handle big or small jobs We have only been going for 2 years In which I have completed some big jobs I’m an honest builder who likes to help people because word of mouth and reputation is the most important part of being a builder I have experience in building trade since 1996 Have worked for large companies Just wanted to try to go on my own
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Guri*s Brothers
No reviews yet
Extension Builder in Welwyn Garden City
Landscaping,gardens,paving,maintenance
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Buildstead Development Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Our team at Buildstead has over 25 years of experience in the construction industry covering a wide range of project types. We truly are your "one-stop shop" when it comes to your project. From design to build, we pride ourselves on our integrity, the quality of our work and the working relationship we enjoy with our clients. With full project management included, you will be kept up to date at each step along the way ensuring complete peace of mind.
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Latest review:
Kitchen Fitting- 5 Nov 2020
An incredibly positive experience from start to finish. I found Robbie and team were hard workers, very likeable and provided brilliant results. Comms throughout were excellent. With Robbie happy to discuss the job over the phone beforehand and put our minds at ease. A big shout out to the team for undertaking this work during COVID. We understand the pressures this places on our tradespeople and we thank Robbie and his team for their diligence and commitment to wearing masks in our home and working safely. A brilliant experience.
Best Bond Brickwork & Construction
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
I'm a fully qualified bricklayer with 12 years in the industry.Im Experienced in all aspects of commercial and residential types of brick/block work. Capable of completing extensions, garden walls,patios, pointing, fencing and plastering. I am a skilled tradesman with a good work ethic and work with a great team .Im happy to work with the client and get the job done to the highest possible standard and in the fastest time.
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Latest review:
Bricklaying- 27 Aug 2021
Mitch and his team were efficient at building the retaining wall in my garden, working on a Saturday to get the job done. The work was completed to a very high standard. The wall had to be left slightly unfinished in order for other works to happen first, so Mitch promised to come back and finish off the wall at no additional cost later in the week. After some chasing, Mitch came back to finish the wall by himself the following Saturday. This was also completed to a high standard. We would highly recommend Mitch’s service for an efficient, high standard output.
SIXTHART LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are an Architectural and Interior Design Studio. We effective planning and technical drawing services. Our Services - Site Survey -All Drawings with Cad Software (Demolish/Proposed) - Draft Planning - Pre Advice Planning - New Build Design - Loft Conversion - Home Extensions - 3D Visulation -Kitchen &Bathroom design projects - Preparation and submission of planning applications - Hourly\Daily Based CAD Services - 3D Modelling (Internal & External Visualisation) -Member of TAG (Traditional Architecture Group) -Bachelor’s Architectural Design Practice -NAAB -TMMOB
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Latest review:
Extensions- 16 Sep 2024
Erhan was excellent. He followed my project from start to finish and kept me updated throughout. Here to the next project!
Florin Lavric
No reviews yet
Extension Builder in Welwyn Garden City
Hi! My name is Florin! I have 4 years experience in carpentry 1st and 2nd fix I can help you with door hanging,skirting,architrave,laminate and wood floors…roofs,and manny more! If you need help and you looking for someone who knows how to do it,contact me!
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JM builders
No reviews yet
Extension Builder in Welwyn Garden City
With 20 years of experience in restoration and refurbishment, I've developed a deep understanding of the field. We are skilled in various aspects of renovation, from initial planning to final execution. We’re committed to delivering high-quality results and ensuring projects are completed efficiently and effectively. Our goal is to provide excellent service and exceed expectations on every project.
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Mark
No reviews yet
Extension Builder in Welwyn Garden City
I do Bathroom , fit laminate flooring and extension
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Mandeep singh
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Hii we do all types of ground work landscaping and demolition on very decent prices
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Latest review:
Groundwork & Foundations- 30 May 2026
Really happy with Mandeep and the team. They are friendly, hard working and helpful. Communication is excellent and honest. I would not hesitate to recommend them
MYD Studio London Limited
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
MYD STUDIO London limited is a Design-Led Architectural and Planning consultancy focusing on New Build ,Extensions, Loft Conversions, Change of use and Flat conversion projects in different Boroughs in London. Whether you are looking to increase the size of your home, make the most of its current size through an internal alteration, or gain planning permission in order to increase its value before selling, we will help you to produce a planning application to meet all of your expectations.
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Latest review:
Extensions- 6 Aug 2022
Majid has been great in producing drawings for our rear extension. He's also helped explain the whole build process to us from design, building inspection, and building. We received our drawings in under 10 days from the initial consultation and site visit. Majid was accomodating and was able to visit the site on weekends for the initial consultation. Always a pleasure to deal with and has been easy to reach over the phone or email. Would highly recommend Maji and MYD Studio London to anyone looking for an architect.
MGA Projects Ltd
No reviews yet
Extension Builder in Welwyn Garden City
MGA Projects Ltd is a trusted London-based construction company delivering high-quality building services from start to finish. We specialise in extensions, full refurbishments, loft conversions, and structural works including steel installations. With years of hands-on experience, we pride ourselves on reliability, attention to detail, and clear communication throughout every project. Whether it’s a small renovation or a full-scale build, we work closely with our clients to bring their vision to life—on time and within budget.
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3.8

Top rated Extension Builders

Our Extension Builders in Welwyn Garden City, 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 Welwyn Garden City?

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 Welwyn Garden City 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 Welwyn Garden City who are available and interested can respond to your post.

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

What are the hourly rates of extension builders in Welwyn Garden City?

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

Find extension builders in Welwyn Garden City with MyBuilder

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

Step 2: Compare different extension builders in Welwyn Garden City

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

Step 3: Hire Welwyn Garden City extension builders with confidence

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

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

What to ask a Welwyn Garden City extension builder before hiring?

Before hiring an extension builder in Welwyn Garden City or extension building company in Welwyn Garden City, 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 Welwyn Garden City?

An extension builder in Welwyn Garden City 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 Welwyn Garden City 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 Welwyn Garden City?

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 Welwyn Garden City 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 Welwyn Garden City 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 Welwyn Garden City

Can an extension builder in Welwyn Garden City help with planning permission?

Yes, many extension builders in Welwyn Garden City 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 Welwyn Garden City handle everything from design to construction?

Many Welwyn Garden City 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 Welwyn Garden City help with materials and finishes?

Yes, most extension builders in Welwyn Garden City 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.