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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Kiseld
No reviews yet
Extension Builder in Welwyn Garden City
Hi, i am a solo trader with 5 years experience in construction, I have a very good knowledge on everything that includes extensions, roofing, full flat refurbishment and good knowledge on other fields too, i looking forward to work for you.
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Cooper’s construction solution
No reviews yet
Extension Builder in Welwyn Garden City
Coopers Construction Solutions is a specialist brickwork company established in 2019 with bricklayers having over 12 years of experience. We pride ourselves on high quality and clean work at a competitive price... always leaving our customers happy!
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ALEX’S ELECTRICAL CREW LIMITED
No reviews yet
Extension Builder in Welwyn Garden City
We specialize in external rendering, providing durable and weather-resistant finishes that protect and enhance properties. Our services cover traditional and modern rendering systems, delivering smooth, stylish, and long-lasting results. With a commitment to quality and reliability, we help transform exteriors into strong, attractive, and energy-efficient spaces.
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Skyline Glass
No reviews yet
Extension Builder in Welwyn Garden City
At Skyline Glass Ltd, we don't just deliver products — we deliver lasting value for your property. We specialise in high-quality glass solutions and expert construction services for both residential and commercial clients across the UK. Our full-service offering includes stunning custom glass designs, precise measurements, premium materials, and flawless installation of windows, doors, partitions, balustrades, balconies, and complete glazing systems — all crafted to elevate the look, functionality, and security of your space. But that's not all. We also provide professional driveway concrete work, creating strong, attractive, and long-lasting driveways that boost your property's kerb appeal. Plus, our home extension services are designed to help you maximise your living space, add value to your home, and create the perfect environment for your family or business. Whether you're replacing outdated fixtures, upgrading your driveway, expanding your living space, or taking on a new build or renovation, we deliver tailored solutions that combine quality, reliability, and superior craftsmanship — all with a keen eye for detail and full compliance with safety standards and building regulations. Transform your property with Skyline G
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Open4way Ltd
No reviews yet
Extension Builder in Welwyn Garden City
Open4way Ltd experienced in general construction,painting,decorating,gardening,block paving,slabs,fencing,cleaning paving with high water pressure,guttering.We have the ability to complete any job,large or small to a very high standard. We are happy to give you a free quote.
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VCNY GROUP LIMITED
No reviews yet
Extension Builder in Welwyn Garden City
We are a dedicated team of experienced, field-based professionals with diverse backgrounds in Health and Safety, Engineering, Project Management and Environmental Sustainability. Our combined expertise allows us to deliver integrated building solutions covering essential services, ensuring each client’s project operates smoothly, efficiently, on schedule and always in compliance with the highest industry standards. At VCNY Group Limited, we pride ourselves on turning ambitious visions into reality by blending innovation with practical, reliable execution. Established on unwavering principles of integrity, creativity and excellence. Our company has earned a leading reputation across the construction and civil engineering sectors. In addition to exceptional building services, we provide expert consultancy to guide clients through complex projects with confidence. From initial concepts to project completion, we remain committed to quality, sustainability and client satisfaction, setting the benchmark for superior results in every endeavour.
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V3 Capital construction ltd
No reviews yet
Extension Builder in Welwyn Garden City
We specialize in providing high-quality repair and renovation services for domestic houses across the UK.
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T.E.T Construction LTD
New on MyBuilder
Extension Builder in Welwyn Garden City
We are the team of professionals that can turn your house into a dream. Quick, reliable and accurate work.
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Kiratpal
No reviews yet
Extension Builder in Welwyn Garden City
We specialize in extensions, bespoke carpentry, and door fitting, alongside complete outdoor solutions including slabbing and fencing. Quality materials, expert installation, and a finish that speaks for itself.
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Rei construction Ltd
No reviews yet
Extension Builder in Welwyn Garden City
We have more than 5 years experience In construction
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DESIGN SEED DEVELOPMENTS LIMITED
No reviews yet
Extension Builder in Welwyn Garden City
We have over 100 years of combined building experience we set up our business to stream line for our clients as we were constantly being let down by tradesman we merged 3 companies together combining heating, gas safe NiC electrical works and all building and brick laying so there is no reason for delays in a project at any given time
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FSB Company (UK) LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
FSB is a well-organized contracting company with a team experienced in large-scale development projects with leading UK construction companies. Based primarily in London, we offer a variety of self delivered services, including complete extensions, and conversions, small works, structural alterations, steel work installations, ground work (foundations, drainage, concrete sub and superstructures), hard landscaping and paving and soft landscaping. We manage our sites carefully and have a digital site management tool kit. Our fully managed service connects skilled tradespeople with experienced construction management directly ensuring attention to detail that begins with our Contractors Proposals and continues through to practical completion and aftercare.
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Latest review:
Extensions- 17 Nov 2025
Freddie, Kaz and Dan are a great team. I felt they were friendly and professional throughout. Any slight niggles were discussed and solutions found, quickly and professionally. They were respectful and went out of their way to get on with all the neighbours. Over all I would say they are a team of very nice people, who care about what they do and take pride in achieving the result their clients are after.
James Murdoch
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Construction company with 27 years experience in the industry between us and a team of other qualified tradespeople necessary to undertake projects.We are new to this site so please ask us to provide you with reference from previous clients. We have experience in timber frame homes, apartment blocks, extensions, renovations and commercial works.We take great pride in our work and make sure every job is completed to the highest of standards on time and on budget. Our aim is your satisfaction.
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Latest review:
Carpentry- 31 May 2017
Was really impressed with these guys. Helped me order the correct garden door and then went to pick up extra bits when the order didn't turn up correctly, for no extra cost and couldn't have been nicer about it, even though it was a pain for them. Really cheerful and helpful - nothing was too much trouble. Would use them again, for sure.
Stark Management Limited
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Accredited with the Federation of Master Builders, TrustMark, Better Business Group and Accreditus Register. Our specialities include New Build Projects, Developments, Extensions and Loft Conversions. We consider ourselves to be different from our competitors as we take on only one project at a time to ensure that we can give our clients our 100% focus and committment.
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Latest review:
New Builds- 24 Jul 2025
job
Robi paiting decorator
No reviews yet
Extension Builder in Welwyn Garden City
We perform work reliably and to a high standard
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Urban Doors&window Glazing Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Welcome to Urbandoor & Window Glazing Ltd! We are your local specialists in doors, windows, and glazing solutions, providing high-quality installations across the UK. Whether it’s bi-fold doors, UPVC or aluminium windows, skylights, or roof lanterns, we combine premium products with expert craftsmanship. Our team is committed to reliable service, precise measurements, and flawless installations. Every project is carried out to British standards, ensuring safety, energy efficiency, and durability. Call us today for a free quotation and let us brighten your home with quality doors and windows!”
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Latest review:
Urbandoorwindowglazing ltd is good team honestly work good price proper neat and clean job. I highly recommended 😍

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.

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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.