Extension builders in Welwyn Garden City

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.6 (18 reviews)

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Some of our top rated extension builders in Welwyn Garden City

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GM CONSTRUCTION LTD
New on MyBuilder
Extension Builder in Welwyn Garden City
We are a professional construction company offering a wide range of building, renovation and property improvement services. Our services include new house builds, home extensions, loft conversions, garage conversions, porches, garden projects and general building work. We also provide bathroom fitting, plumbing, kitchen fitting, electrical work, tiling, painting and decorating, carpentry, flooring, concrete and screeding, underfloor heating, boiler installation and servicing, and drywall installation. From complete property renovations to individual home improvement projects, we aim to deliver quality workmanship, reliable service and clear communication. We work closely with our customers to understand their needs, discuss project requirements and provide solutions suited to their budget. Whether you are planning a new build, upgrading your kitchen or bathroom, converting your loft or garage, or renovating your entire property, we are happy to discuss your project and provide a quotation. Customer satisfaction, professionalism and attention to detail are important to us.
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C&L Construction services LTD
No reviews yet
Extension Builder in Welwyn Garden City
At C&L Construction Services Ltd, we specialise in providing a complete construction service delivering refurbishment, development and maintenance services. We work on any projects from homeowners looking to extend complete /refurbishment of bathrooms and kitchens, modernisation for smart homes and automation systems and a full project management and design service. We can advise on material selection help navigate the minefield of planning building and health and safety regulations
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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.
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.
Infuse Construction Limited
New on MyBuilder
Extension Builder in Welwyn Garden City
Experienced Construction Contractor | Residential & Commercial Projects With over 12 years of trading and led by a Chartered Surveyor with 40 years of industry experience, we deliver high-quality construction projects from concept to completion. We offer general contracting, design & build and turnkey solutions through our trusted team of architects, engineers and specialist consultants & contractors, ensuring every project is professionally managed from start to finish. Our residential expertise includes new build homes, listed buildings, barn conversions, loft conversions, extensions and property conversions. Our commercial experience includes KFC new build, children's nurseries, shopping centre and retail park landlord works, and five-a-side football centres. We pride ourselves on a personal, hands-on approach, building strong client relationships through clear communication, reliability and attention to detail. We aim to deliver projects on time, within budget and to the highest standards, providing practical advice and solutions throughout. We are backed by comprehensive insurance for complete peace of mind: £5m Public Liability, £5m Employers' Liability and £2m Professional Indemnity Insurance.
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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.
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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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.
Sandhu construction
No reviews yet
Extension Builder in Welwyn Garden City
Sandhu Construction is a results-driven construction firm committed to delivering high-quality residential and commercial building projects. Our team specializes in comprehensive site management, expert craftsmanship, and modern infrastructure solutions—ensuring every fitting and installation meets the highest industry standards for safety and durability.
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GP Construction Services Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
New build, extensions, loft conversion, glazing, roofing, electrical and plumbing
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Latest review:
We recently bought flat to let and decided to do completely refurbish. We invited few quotations including Gurwinder. We shortlisted top 3 quotation and invited him for discussion. During the meeting he was very professional and full of ideas. So we decided to honour him. Work started as agree on time, during the Job we liked his ownership of the work and advising us on the very step of the decision. Although it would have been better if his communications were more punctual but it neither affect us nor delayed any work. Even after completion he has been very helpful if any issue arises ( nothing major).
Rocky
Rating: 4.8 out of 5
Extension Builder in Welwyn Garden City
We are undertaken all type of work speacialist in brick work
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Latest review:
Groundwork & Foundations- 30 Oct 2026
Quickly and efficiently work done.
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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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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Joy Design & Build LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Joy Design & Build – Where every project is a promise of exceptional quality, unwavering integrity, and cutting-edge innovation. We specialize in transforming your vision into vibrant, functional spaces that truly reflect your needs and style. Whether you're dreaming of a bespoke home that captures your unique personality, a commercial space designed to inspire productivity and creativity, or a thoughtful renovation that breathes new life into your property, we are here to turn those dreams into reality. At Joy Design & Build, we take pride in our meticulous attention to detail, our commitment to sustainable practices, and our collaborative approach with every client. From initial concept to final construction, we ensure that each project not only meets but exceeds your expectations. Your vision deserves more than just a construction project—it deserves an experience that’s seamless, stress-free, and tailored to your goals. Let’s build something extraordinary together.
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Latest review:
The works was clean , neat and well organised
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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4.6

Top rated Extension Builders

Our Extension Builders in Welwyn Garden City, are rated 4.6 out of 5 based on 18 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.