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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jc_electrical
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are a construction company with years of experience in all aspects ranging from groundwork, carpentry, extensions and many more. We pride ourselves on delivering a high quality finish.
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Latest review:
Landscaping- 20 May 2026
Very pleased. Responsive and did a good job
Arcus Construction Ltd
No reviews yet
Extension Builder in Welwyn Garden City
Arcus Construction was formed with the view to deliver the highest quality standards alongside exceptional customer service, making the construction process simple, seamless, well managed and entirely positive for our clients. As refurbishment & construction specialists, our multi-skilled team covers all trades, enabling us to provide a complete in-house, end-to-end service, which is managed & completed to our own impeccably high standards
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Viranna Professional Building and Cleaning Service Ltd
Rating: 4.4 out of 5
Extension Builder in Welwyn Garden City
Viranna Brickwork Contractors are actively looking to take on more work and would like to be in your tender list. We are based in Surrey, South Croydon, but travel and work all over the South East. We have over 10 years’ experience in the Building industry and taking pride in the job. Looking forward to work with you on your next project. Viranna Professional Building and Cleaning Service LTD
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Latest review:
Bricklaying- 26 May 2020
Very professional and reliable. Quality of work is very high standard and will definitely use their services again. Come highly recommended.
Boundary builders
No reviews yet
Extension Builder in Welwyn Garden City
Family run company specializing in making more space extensions, loft conversions, out buildings,new builds. we can take the stress out of building for you from the start to finish with setting out architecture drawings building control structure build and interior ..
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Matteo construction Ltd
No reviews yet
Extension Builder in Welwyn Garden City
Hi there hope you’re all keeping well I would like to introduce myself and my company Matteoconstruction Ltd I kindly ask if you could take a moment and visit our website site and see the service that we offer Please share with me if there is anything that we can assist you in the future with your work loads Kind regards Flo At Matteoconstruction Ltd
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D&DGeneral Building Construction
No reviews yet
Extension Builder in Welwyn Garden City
D&D General Building Construction with more than 22 years experience in a Construction sector as commercial and private property , ( Registered with Federation of Master Builders & UK Degree Civil Engineering ) is committed to excellence in every aspect of our operations. From the initial consultation to the final walkthrough, we ensure that every project reflects our dedication to our clients’ satisfaction, environmental responsibility, and the highest standards of quality. Join us as we continue to build a better future, one project at a time.
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Home Renovations Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We're a building company specializing in house extensions, loft conversions and refurbishments. Our clients come from New Malden, where we're based, but also surrounding areas. The vast industry experience enables us to provide valuable advice, professional services and individual approach, benefiting our customers. As we understand trust and credibility are crucial when undertaking such projects, we arrange viewings and provide customers with references and photos of our most recent projects.
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Latest review:
Extensions- 24 Jun 2017
We had a large piece of work done by Johan and his team. It was a 4m single storey rear extension with new kitchen installation, converting the old kitchen into a downstairs bathroom and utility room, plus other bits and bobs like new boiler, rear patio. We got quotes from a few builders, Home Renovations weren't the cheapest, they were actually towards the higher end. But we went and saw their previous work and spoke to some of their other clients. The work was done to a high quality and the clients seemed to be happy so we decided to go with them. Johan's team are very hard working, professional and polite. Pawel and his team of builders, bricklayers, plumbers, electricians, etc. would turn up before 8am and finish at 6pm working solidly throughout the day. There is Magda as the project manager who keeps you in the loop, and answers any of your questions (which we had many). There is Michaela on the finance side who keeps you up to date with the budget. Our budget went over by 5% with "variations" (extra work or materials) but it was always communicated why and the work wasn't done without our approval. Pawel would give his recommendations but the final word would always be ours. But these things can add up. Overall we were very happy with the build, it was done to a very high standard. They also finished it before time. They said it would take 12 weeks in fact they finished it in 10 weeks which was amazing as you would normally expect these things to go over.
A.S.L Corporation LTD
No reviews yet
Extension Builder in Welwyn Garden City
A.S.L Corporation Ltd, stands as a powerhouse in the UK construction industry. Based in London but serving the entire nation, we operate under a singular, driving philosophy: "Built Strong. Built Right." Our brand is defined by a commitment to civil-engineered results that prioritize structural integrity and aesthetic precision. We bridge the gap between high-end quality and affordability, offering a Best Price Guarantee that ensures our clients receive premium construction without the premium price tag. Our "no shortcuts" approach is backed by a dedication to on-time delivery; we respect your schedule by starting promptly and finishing according to plan. Our versatile service portfolio covers every stage of property development. We handle heavy structural work, including extensions, lofts, and garage builds, alongside refined interior services like bespoke kitchen fitting and tiling. Our expertise extends to the exterior with professional roofing, painting, and civil works. To ensure long-term value, our maintenance and "Deep Finish" teams provide specialized care, from gutter restoration and roof cleaning to driveway jet washing and protective sealing. At Beast Construction, we transfor
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IVD Construction Ltd
No reviews yet
Extension Builder in Welwyn Garden City
Hello, I’ve been in the construction business for more than 13 years. I’ve been doing high end projects including basement excavation works, new roofs, extensions, full internal renovations, plumbing and electrical works, etc. My company works with high skilled professionals to satisfy all customer needs.
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R & R Brickwork ltd
Rating: 4.7 out of 5
Extension Builder in Welwyn Garden City
I've been a bricklayer for 30 years. We specialise in all forms of Brickwork and block work from garden walls to extentions, new builds, patio and driveways. Work of all sizes undertaken.
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Latest review:
Bricklaying- 26 Aug 2021
I cannot recommend Rob and his 2 sons highly enough, they have done an excellent job completing the brickwork for our large outbuilding in good time and at a reasonable price. 3 genuinely nice blokes who are hard working and thorough, we wouldn't hesitate to use them again and have already referred for work elsewhere.
AJ Partners Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are family business working in different levels of building industry. Refurbishment, supply and fit and installation service. Carpenter, Joinery, Tiling, Plumbing, etc. Supply or supply and fit, refurbish and new build We completed various projects in London and surrounding areas We listen to our clients needs and liaise with you throughout your project to ensure that the project finishes on time and on budget. Trades 15 Years of experience and good reviews leads our work.
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Latest review:
Kitchen Fitting- 7 Jun 2020
We liked Alex from the first meeting and the first impression was spot on. Alex did an amazing job on our kitchen, which was half initiated by another tradesman. He reviewed the work and fixed many issues, always explaining and communicating well. Our kitchen had to be adapted and had some non standard cabinets but Alex was able to do all the additional features we asked for and with a great result. He also recommended some design changes which we agreed to and love. He finished the work, reviewed everything and signed off, always with a smile which is a plus. Definitely highly recommended and we will call him again in the future for sure. Thank you Alex!
LSTAR CONSTRUCTION LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
From the first brick to the final detail – we turn your vision into reality.
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Latest review:
When I was looking for quotes, Lukasz was the only builder who provided a fully detailed breakdown. From the start, he was professional and punctual, arriving exactly on time for our first meeting. He offered great recommendations on the best ways to approach the refurbishment and was flexible enough to let me source my own materials. Most importantly, he provides a warranty which he has already honored to fix a minor fault from another professional. It has been a pleasure trusting Lukasz and his team with my full house renovation.
MR BUILDING
No reviews yet
Extension Builder in Welwyn Garden City
Hi we are professional builders experience more than 10 years we do all building work such as bathroom and kitchen renovation tiling flooring and loft,extensions.
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BLUE LOFT CONSTRUCTION LTD
No reviews yet
Extension Builder in Welwyn Garden City
Design, Build & Remodel We pride ourselves on our commitment to provide a professional and speedy service at all times, whilst maintaining the highest quality of work. We take on all types of jobs from small domestic work to larger commercial projects, all carried out to the highest standards, and at very competitive prices. We take on all building work from plumbing and electrics to conversions and extensions. Contact us today to discuss your requirements.
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Pal
New on MyBuilder
Extension Builder in Welwyn Garden City
For a strong Thumbtack company description, focus on being professional, clear, and personable. You want to convince potential customers that you are the best person for their specific job.
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Chaman singh
No reviews yet
Extension Builder in Welwyn Garden City
Hi, my name is chaman kamboj I have been working in construction industry for 5 years now , I can work far aswell around 50 miles from west london, I give neat and quality work no compromise with it and reasonable price ,
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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.