Extension Builders in Welwyn Garden City

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.9 (16 reviews)

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Some of our top rated extension builders in Welwyn Garden City

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MD Property
No reviews yet
Extension Builder in Welwyn Garden City
Welcome to our profile MD Property is a well established landscaping & building firm. We cover an array of services from laying some turf to multi storey extensions & loft conversions. We love what we do and wouldn’t change it for anything! the pride, joy & sense of self accomplishment we have in all our work sets us apart from the rest! We put the customer at the forefront of our business as they are the people that really matter. Thank you for looking at our profile, we hope to see you soon.
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Complex design and build ltd
No reviews yet
Extension Builder in Welwyn Garden City
We are a construction company. We specialise in all types of building works commercial and residential. Over the past years we have built loft conversions, extensions, new build houses and are currently on a commercial refurb building 14 flats.
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Toni
No reviews yet
Extension Builder in Welwyn Garden City
We are a London-based construction company delivering high-quality building solutions across the capital and beyond. Specialising in residential and commercial projects, we provide reliable, end-to-end services—from planning and groundwork to final completion. Our focus is simple: quality workmanship, clear communication, and projects delivered on time and within budget. While we are proudly based in London, we also undertake projects across the UK, bringing the same level of professionalism and attention to detail wherever we work. Whether you’re planning a new build, renovation, or extension, we work closely with you to turn your vision into reality.
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landcraft improvements
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Hi John here. Thank you for viewing my profile. I have been in the family business of landscaping and roofing construction work for many years gaining lots of experience form many types of projects. I offer competitive rates and aim to offer professional advice and carry out work to a high standard. Thank you again John.
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Latest review:
Roofing (Pitched)- 5 Mar 2024
John, an all round great person to deal with. Very helpful and did an excellent job. Would def recommend. :)
Rise Group Holdings
No reviews yet
Extension Builder in Welwyn Garden City
**Profile:** Hi there, I’m a 43-year-old Project Manager with extensive experience in construction and a background as a trained carpenter. Over the years, I’ve had the privilege of working on a variety of projects, from loft conversions and extensions to full refurbishments. My approach is grounded in honesty, hard work, and delivering on promises. I believe in providing clear and inclusive quotes that I can confidently stand by, ensuring transparency and peace of mind throughout the process. Myself and my team are professional, friendly, and dedicated to getting the job done right, every time. Whether you’re planning a small renovation or a large-scale transformation, I am here to help bring your vision to life with skill, reliability, and attention to detail. Feel free to get in touch if you’re looking for someone who takes pride in their work and is committed to delivering exceptional results!
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TL BRICKWORK
No reviews yet
Extension Builder in Welwyn Garden City
We are a family run business and have been trading for over 15 years in the construction industry, we have a very experienced workforce that are willing to go above and beyond for our customers. We specialise in all aspects of the construction industry.
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Shonan carpentry and building services
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
I’m a Qualified NVQ Carpenter and joiner with 17 years experience in residential and commercial construction industry. I lived in Japan for 3 years and whilst there learnt Japanese carpentry skills. I pride myself in making sure the customer is happy and the quality of my work is second to none. communication between customer and myself is key to making sure the job runs smoothly. Carpentry Maintenance Kitchen fitting Wood flooring Refurbishment
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Latest review:
I have employed Jordan Wade many times to work on my properties, his primary trade is a fully qualified carpenter, though any other activity such as plaster boarding and kitchen installations that he has carried out for me has been of top quality. He's always on time and has never let me down when he says he will turn up, he turns up, I can certainly highly recommend Jordan
Sefolli
No reviews yet
Extension Builder in Welwyn Garden City
We know it can be hard to find a builder that you can rely on. The owner, Artur Sefolli (F) has a wealth of experience and is known as one of the best builders. We pride ourselves on providing a professional, caring and high-quality service and always meet our customers’ needs. Sefolli Building is fully experienced, timekeeping, quality of work and value. We offer a full range of building services, from major rebuilds to smaller jobs such as masonry repairs Our services include: Alterations Extensions Basements Garages Brickwork Roofing Services Driveways Gardening Groundworks Excavation Foundations External Works Underpinning Concrete Screeding Flooring Painting Decorating Fences Paving Landscaping Re-pointing Soakaways Manholes Drainage If you are trying to find a builder near you, why not give us a call? Our friendly, professional team will be happy to talk through your needs and give you a free quote.
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M&J
No reviews yet
Extension Builder in Welwyn Garden City
I am 29 years old. I really like working in construction. I have been working for 5 years in a company and now I want to do something for myself because I believe that I have all the necessary qualities and I want to start something for myself.
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Decor Bros Ltd
No reviews yet
Extension Builder in Welwyn Garden City
About Decor Bros Ltd Decor Bros Ltd is a trusted provider of high-quality painting, decorating, loft conversions, full house refurbishment and summer house extensions across the UK. With a commitment to excellence, we transform residential and commercial spaces with precision, creativity, and durability. Our skilled team specializes in: ✔ Painting & Decorating – Delivering flawless finishes for interiors and exteriors. ✔ Loft Conversions – Maximizing space with innovative and functional designs. ✔ Summer House Extensions – Creating stylish and practical outdoor living spaces. At Decor Bros Ltd, we take pride in delivering exceptional craftsmanship, personalized service, and timely project completion. Whether you’re a homeowner, landlord, business, or developer, we tailor our solutions to meet your unique needs. Let us bring your vision to life with quality you can trust. Get in touch today for a consultation! 📍 Operating UK-Wide
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ZGS Carpentry
New on MyBuilder
Extension Builder in Welwyn Garden City
I’m a young, fully qualified carpenter and joiner with a real passion for quality workmanship. I have experience across all aspects of carpentry and joinery, from first-fix and second-fix work to doors, flooring, kitchens, roofing, bespoke work and much more. I take pride in delivering a high-quality finish, working professionally and leaving every job clean and tidy. Whether it’s a small repair, home improvement or a larger project, I’m always happy to discuss your requirements and provide a reliable service at a competitive price.
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Top capital construction
No reviews yet
Extension Builder in Welwyn Garden City
We in building industry for last 17 years. We do any carpentry/ joinery works as instalation doors, windows, stares, warddribes etc. Also we do extentions, loft conversion and any refurbishment.
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Highpoint roofing and building contractors
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
At Highpoint roofing and building contractors we have over 40 years of experience Collectively, we take pride in our work to ensure 100% customer satisfaction With our free no obligation quotation you will be given all the advice you need to ensure total piece of mind our goal is to meet and exceed expectations of every customer all work carried out to the highest Possible standards and at very competitive prices
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Latest review:
Roofing (Flat)- 6 Jan 2026
Completed the job as promised and was very tidy in his job
K&S Design Build Ltd
No reviews yet
Extension Builder in Welwyn Garden City
We have a committed team working on a range of different projects throughout London, working in all sectors including; residential, commercial and conservation. The services that we provide are, architectural and structural 2d & 3d designs, calculation, planning permission, building control, new build, refurbishment, self contained flats, loft conversion, rear and side extension plus much more. I have over 30 years of experience in construction and have worked on a variety of different projects, from small developments to managing large scale Projects.
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Louis Dowling
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
I take pride and joy in any job I am doing, always take extra time to make sure the customer is totally satisfied and understanding, there is no job to big or too small so please don’t hesitate to get in touch - I range from groundwork’s such as installing drainage or digging footings to building extensions or garden walls/piers, also specialise in repointing. I also do a lot of landscaping work such as patios, driveways, fencing concrete shed bases etc… so please feel free to get in touch
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Latest review:
Landscaping- 10 Sep 2026
Louis made a difficult job very easy by sorting all the logistical problems of removing and disposing of an old patio and getting all the new stone and aggregate delivered where there was no easy access to the back garden. He worked continuous days until the job was done and finished in good time and on the budget we agreed, which was very reasonable. Louis did the job to the spec we wanted, including cutting mitre corners on narrow concrete edging, and was very clear when offering us different options, such as how to join the patio to the side passage. Everything was cleared up at the end, and the finished patio looks exactly as we had hoped it would. Louis was always polite and is a hard worker who takes an obvious pride in doing the job properly.
STONE SA LIMITED
No reviews yet
Extension Builder in Welwyn Garden City
Stone Sa Construction can give you the help and essential advice needed to optimize the space and construction of your building project, but also provide a quality of service.
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3.9

Top rated Extension Builders

Our Extension Builders in Welwyn Garden City, are rated 3.9 out of 5 based on 16 reviews from customers like you.

Quality screening

Easily find verified local tradespeople. Just post your job to get quotes from tradespeople near you across the UK.

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.