Extension Builders in Welwyn Garden City

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.7 (13 reviews)

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Some of our top rated extension builders in Welwyn Garden City

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FERARU GROUP BUILDERS LTD
Rating: 4.7 out of 5
Extension Builder in Welwyn Garden City
I've worked in the UK for 8years now and I do my job to a high standard.
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Latest review:
Extensions- 15 Jun 2024
My advice is avoid. Poor communication Poor workmanship Poor quality finish Create 'issues' during build to make you pay more than quoted Left project incomplete We pursued through the Court and won the case, but of course he is unable to pay, so we are pursing further through the Court. He will respond to the review with some excuse, but there is absoultley no excuse for poor workmanship and quality. Happy to share pictures and videos on request.
Pro-House Builders & Decorators
No reviews yet
Extension Builder in Welwyn Garden City
I have been working as a designer for 13 years. This is not only my job, but also my passion. I love making changes to people's homes, improving their comfort, I listen to my clients and always work closely with them to build their home exactly the way they want. My experience helps me quickly come up with ideas for clients' needs, and I act quickly in case of various types of problems and uncertainties. I always work to a high standard and pay attention to detail - these are my strengths. I work with my business partner in London, Surrey, Kent, Essex and any other reasonable distance. We are always happy to provide a free quote
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Y&F Building and Decoration
New on MyBuilder
Extension Builder in Welwyn Garden City
Building & Decoration is a premier contracting company led by a professional electrical expert. We specialize in high-quality home renovations, offering a complete service from structural work and expert electrical installations to premium interior decoration. With our technical background, we ensure every project is safe, compliant with regulations, and finished to the highest aesthetic standards. Your vision, built on a solid and safe foundation."
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CIRCLELETTINGs london limited
New on MyBuilder
Extension Builder in Welwyn Garden City
an experienced builder with good knowledge of building, plastering, tiling job
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ibuilder service ltd
No reviews yet
Extension Builder in Welwyn Garden City
extension
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Vb development
No reviews yet
Extension Builder in Welwyn Garden City
VB development here to make your dream house.
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Delta Build Services
No reviews yet
Extension Builder in Welwyn Garden City
collectively have experience of about 10 years, done several complete refurbishments, single and double story extensions, loft conversions. have done a newbuild warehouse from scratch to complete. have good experience of electric, plumbing, and joinery. qualifications for electrics are part P of building regs., 17th edition and Inspection & testing. Electric certificates will be provided through NICEIC.
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Jplbuilders
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Our company specializes in high-quality renovations for bathrooms, kitchens, entire homes and gardening. We offer a wide range of services, including carpentry, custom woodworking, and general home improvements. With a focus on craftsmanship and attention to detail, we ensure every project meets your expectations. Whether you're updating a single room or remodeling your entire property, we’re here to bring your vision to life."
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Latest review:
Carpentry- 6 Dec 2024
Jerry was excellent and delivered a fabulous job, and I am very happy with the outcome! Highly recommended!
TJ Elite Building Services LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We have a team of qualified builders, electricians, plumbers, roofers to mention a few covering all aspects the building services we offer. Accumulating over 10 years of experience, covering all requirements of our customers, we aim to deliver a high quality service for your requirements We can provide all aspects of job to be covered from start to finish, from drawing plans, approval to the high quality finish of the job.
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Latest review:
Diligent, professional and finished job to a high standard. Only needed flooring done in all rooms but after seeing the quality of work, had further work carried out in gardens front and back. Have had no issues since and hes the one family goes to for any jobs that need doing, as know work gets done and we can trust that it will be of high standard.
Jass
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We do all kind of staircase with fill finishing, Roofs Structure, Roof Tiles , installing doors , Flooring and other construction work.
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Latest review:
Carpentry- 1 Jul 2026
Jass was quick to respond and gave a good price for fabricating a staircase on site. Jass made sure I was happy before leaving and readjusted one of the steps which was creaking.
Acorn build
No reviews yet
Extension Builder in Welwyn Garden City
Hi my name is Robert I have been in the industry for 30 years I’m cis regestered I have worked between site work and private contracts troughtout the country my reputation can be proved via my previous employment who have always appreciated my work. Bricklaying plastering patios and fencing
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Thomas Wicks Building Services Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are a growing domestic building company, with 20 years of experience carrying out all aspects of residential building projects. Extensions, Kitchens, Bathrooms and all of the related services such as Plumbing, Tiling, Electrics. We pride ourselves on giving the customer exactly what they want, making the experience of improving their property an enjoyable one.
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Latest review:
Bathroom Fitting- 2 Jan 2018
Tom was brilliant from start to finish. Clean and very personable, we have used him again since and will do in the future.
Amritpal singh
Rating: 4.5 out of 5
Extension Builder in Welwyn Garden City
We are here to assist you and provide you the work you dreamt off on very reasonable prices so trust us with your house and we will do the best for you .please do understand that we have to pay to get contact details of customers so it’s important being a customer to check the portfolio before short listing a tradesman just to be sure that we won’t just be paying for nothing .
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Latest review:
Extensions- 4 Jan 2026
I hired Amrit based on positive reviews, but my experience was extremely poor. The work showed all the signs of a cowboy builder. I’m sharing this to help others avoid the stress, delays, and financial risk I went through. 1: No Respect for Contract or Deadlines Contract deadline was 15th September, which he completely missed. Despite delays, he demanded money almost daily. When I referred him to the payment and work schedule he signed, his response was: “I didn’t read it, I just signed it.” 2: Dangerous and Unprofessional Working Practices Brought in unqualified workers, many of whom could not speak basic English. He ignored safety standards throughout the project and wanted to use the same unqualified workers for gas work, which is extremely dangerous. When I objected, his response was: “Don’t worry, you will get a new house if it blows up as you have insurance.” 3: Work failed multiple building control inspections. He eventually refused to cooperate with the building inspector.
Ss construction
No reviews yet
Extension Builder in Welwyn Garden City
With over 20 years of experience in the construction industry, our company has built a strong reputation for delivering high-quality projects with reliability and precision. We specialize in residential, commercial, and renovation projects, ensuring every build meets the highest standards of craftsmanship, safety, and durability. Our dedicated team works closely with clients to turn their vision into reality while completing projects on time and within budget.
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Saharan Enterprises
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
we create beautifully crafted interiors that combine luxury, elegance, and exceptional craftsmanship. Specialising in bespoke kitchens, fitted wardrobes, and premium carpentry services, we transform ordinary spaces into timeless works of art. Every project is carefully designed to reflect your style, maximise functionality, and add lasting value to your home. From sophisticated modern kitchens to handcrafted wardrobes and custom woodwork, our skilled craftsmen deliver flawless finishes with meticulous attention Our Services * Luxury bespoke kitchens * Custom fitted wardrobes * Premium carpentry and woodwork * Elegant storage solutions * Professional design and installation * Tailor-made finishes to suit your lifestyle
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Latest review:
Kitchen Fitting- 21 Jun 2026
Quick and very efficient, replaced worktops, cupboard doors and drawers and fixed bathroom tap. Highly recommend
APNA GROUP UK LIMITED
No reviews yet
Extension Builder in Welwyn Garden City
We take on variety of projects,small to large. we have been in the building trade for the last 15 years. General builders, loft specialist, roofing, refurbishments of properties.We also specialise in External wall insulation along with keeping your property warm in the current climate.
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3.7

Top rated Extension Builders

Our Extension Builders in Welwyn Garden City, are rated 3.7 out of 5 based on 13 reviews from customers like you.

Quality screening

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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.