Extension Builders in Welwyn

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

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Peter Building's service
No reviews yet
Extension Builder in Welwyn
I am a generał builder,I Arive on time,I have no addictions ,I have bęben on the UK for 16 years,I am cery precise,I like doing what I do.
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T and s building ltd
No reviews yet
Extension Builder in Welwyn
Referbishments new builds and extensions Trading for 25 years. Good reputation. Most work is by recommendation.
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A&AK CONSTRUCTION LTD
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Extension Builder in Welwyn
Hello my name is sandeep kapoor and I am a dedicated builder with almost 12 years of experience starting my journey in this Industry in 2013.Over the years, I’ve honed my skills in various aspects of construction, from residential projects to commercial builds. I’m proud to be registered with Delta membranes , which reflects my commitment to quality and professionalism. I believe in creating spaces that not only meet my clients’ needs but also exceed their expectations. My approach combines meticulous planning, attending to details and focusing on communication in order to run projects smoothly from starting to finish.
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Elite Renovations Limited
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Extension Builder in Welwyn
Renovation work. From boilers to bathrooms, kitchens to decorating. We cover it all. We started off as a plumbing firm 8 years ago and have now expanded to a full renovation company.
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SANDHU A1 construction LTD
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Extension Builder in Welwyn
All Building Work Undertaken:- * Extension * Bathroom * Plumbing * Carpentry * Kitchen * Loft Conversion * Electrics * Heating
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Sfg constructions
No reviews yet
Extension Builder in Welwyn
Hi, I’m a reliable and hardworking individual with experience in kitchen fittings, floorings, bathroom fitting, loft conversions, . I’m passionate about providing excellent service and always go the extra mile to ensure customer satisfaction. I’m punctual, detail-oriented, and take pride in doing the job right the first time. Whether it’s delivering with care or handling tasks efficiently, I’m here to help make your day easier.
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DRYPSIAK
No reviews yet
Extension Builder in Welwyn
Hi! My name is Viktor. My team and I are professional carpenters with over 7 years of experience in construction. We have received many great reviews from our customers. We specialize in both first and second fix carpentry, as well as any kind of woodwork. We take pride in delivering high-quality craftsmanship, always meeting deadlines and ensuring customer satisfaction. Whether it’s framing, flooring, doors, windows, or custom woodwork, we approach every project with precision and attention to detail. No job is too big or too small — we’re ready to help bring your vision to life.
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Mat's Group Limited
No reviews yet
Extension Builder in Welwyn
Mat’s Group Ltd is an experienced construction and refurbishment contractor delivering high-quality residential and light commercial projects across London and the South East. We specialise in extensions, loft conversions, structural alterations, full refurbishments, and new build developments. Our team combines practical site expertise with strong project management, ensuring works are delivered safely, on time, and within budget. We regularly undertake structural works including foundation construction, steel installations (RSJs), underpinning, roofing, and complete internal fit-outs. As a Principal Contractor, we operate in full compliance with CDM 2015, maintaining high standards of health and safety, workmanship, and communication throughout every project. We pride ourselves on reliability, transparent pricing, and attention to detail. From small residential improvements to larger developments, we work closely with clients to achieve quality results with minimal disruption. Mat’s Group Ltd – Building with confidence.
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NV Constructions LTD
No reviews yet
Extension Builder in Welwyn
New build house , extensions ,renovation, loft convention all Bulding work undertaken
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Knights roof Ltd
No reviews yet
Extension Builder in Welwyn
Knights Roof specialises in top-quality roofing, loft conversions, and timber work. We’re fully insured, highly rated, and committed to clean, timely work on every job. Fast-track roofing service available – because your time matters. With a focus on lasting craftsmanship and customer satisfaction, we treat your home like our own. We don’t just build roofs—we build trust. Free quotes & honest advice—every time.
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Croftley Projects
No reviews yet
Extension Builder in Welwyn
We are a local based company supplying and installing high end windows, doors undertaking block and brickwork extensions as required with a local team of highly experienced tradesman. We cover both commercial and domestic clients, we can also provide replacement glazed units, construction materials and undertake full surveys as required. Over 20 years experience.
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Ligna Homes Ltd
No reviews yet
Extension Builder in Welwyn
Although very new to MyBuilder, we have over 20 years experience offering a friendly, helpful and comprehensive service for all of your timber framing, hand cut roofing and general carpentry needs.
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Cranham village construction
No reviews yet
Extension Builder in Welwyn
General building, maintenance and repairs.
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Jjbrickwork
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Extension Builder in Welwyn
Hi jjbrickwork im a local bricklayer over 10 yrs of experience. No job to small from repair work , garden walls extensions and new builds message for a free no obligation quote tx
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Executive Constructions Ltd
No reviews yet
Extension Builder in Welwyn
Hai , We are from Executive construction, we will help you to make New build homes , Roofing , Foundations , Landscaping, Rennovations and Driveways installer . Moreover , we will share with you new trending ideas and will work with full experience
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Junaid Ahmed
No reviews yet
Extension Builder in Welwyn
We are doing all kind of building works loft conversion, single or double storey extension, new build homes. Also we don’t charge any upfront, we will charge our clients after the work done and approved from building control
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3.8

Top rated Extension Builders

Our Extension Builders in Welwyn, 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?

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 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 who are available and interested can respond to your post.

Browse profiles, read customer reviews and get quotes from your chosen Welwyn extension builders, all before you decide who to hire.

What are the hourly rates of extension builders in Welwyn?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Welwyn 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 extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Welwyn home extension project is likely to cost.

Find extension builders in Welwyn with MyBuilder

Hiring the right extension builder in Welwyn 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 extension builders. Once your job is live, we’ll share it with home extension builders in Welwyn who can express their interest.

Step 2: Compare different extension builders in Welwyn

When you start receiving interest, review profiles of local Welwyn extension builders, check their previous work, and read real customer reviews. Ask about timelines, materials, and request detailed quotes.

Step 3: Hire Welwyn extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Welwyn, 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 extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Welwyn extension builder before hiring?

Before hiring an extension builder in Welwyn or extension building company in Welwyn, 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?

An extension builder in Welwyn 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 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?

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 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 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

Can an extension builder in Welwyn help with planning permission?

Yes, many extension builders in Welwyn 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 handle everything from design to construction?

Many Welwyn 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 help with materials and finishes?

Yes, most extension builders in Welwyn 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.