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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CTA BUILDING CONTRACTORS LTD
No reviews yet
Extension Builder in Welwyn
my company runs : house from scratch, extension,loft conversion, roof ,plumbing, electric, we provide certificate for plumbing and elctric, new bathrooms, full refurbishment ,paving, we large team and we take the work in serious, every job new challenge
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Simarji Singh
No reviews yet
Extension Builder in Welwyn
At Simar Construction, we bring craftsmanship and design together to transform your home. Whether it’s a luxury kitchen, a bespoke bedroom, or a full home renovation, our skilled team delivers quality you can see and service you can trust. We handle every aspect of your project — plumbing, electrical work, loft conversions, house extensions, and driveways — all completed with precision and care. With years of experience and a commitment to excellence, Simar Construction ensures your home is built to the highest standard — from concept to creation.
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BuilderMaan Limited
No reviews yet
Extension Builder in Welwyn
We are a new company who have experienced builders for over 10 years specialising in residential building work. We have successfully completed projects which include whole house renovation to smaller work such as single storey extensions and garages. We have a highly dedicated team who pride themselves in creating the customers needs within the most competitive rates in the market.
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DM Builder
No reviews yet
Extension Builder in Welwyn
I am a general builder and have 15 years experience in the trade. I have worked for large companies which have enabled me to gain a vast knowledge in many areas. I have completed large refurbishments to smaller projects. I work with qualified Electricians and plumbers so am confident that I can complete tasks.
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Cyrus Consulting Civil and Structural Engineers Ltd
No reviews yet
Extension Builder in Welwyn
Our services typically include structural design calculations and detailed drawings for building control submissions. We have extensive experience designing with traditional materials such as steel, concrete, masonry and timber on varied projects including new build residential and commercial buildings, alteration of existing structures, extensions, loft conversions and basements.
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Ivan Martinciuc
No reviews yet
Extension Builder in Welwyn
Hello, my name is Ivan, I have been professionally involved in repairs for more than 5 years and have CSCS level 2 NVQ Carpenter and Joinery certification. I guarantee you quality work at a reasonable price. Thank you.
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BSB Builders
No reviews yet
Extension Builder in Welwyn
With 15 years of experience in the building trade, I offer a full range of building services, specialising in tiling, plumbing, painting, and extensions. I have built a strong reputation for quality workmanship and reliability, earning excellent reviews from my clients. My work spans both residential properties and commercial spaces, including high-end clothing stores. I take pride in delivering professional results, no matter the project size. I am based in West London and cover all of London and outer London. My main priority is client satisfaction and making sure my client is happy with the work we do. As a homeowner myself, I am aware of the clients situation and the importance of doing what my client wants to the best standard possible.
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Tmbl carpentry ltd
No reviews yet
Extension Builder in Welwyn
Tmbl carpentry ltd. We are a small carpentry company specialising in kitchen fitting, loft conversion and extension and all aspects of home development. Our otherside of the business we do commercial fitouts. Office interiors, property maintenance, shop fitouts. We have a over 50 years of combined experience in construction and can provide a multi trade team to cater for all domestic and commercial projects.
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Express Moves
No reviews yet
Extension Builder in Welwyn
All building work from loft conversions to basements. Internal restructuring, kitchens and bathrooms. Any job small or big undertaken. Approved building control work. We welcome any jobs you have and are happy to quote or advise free of charge. Honest and straightforward ethics. Very competitive rates.
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CIVIBUILD LTD
No reviews yet
Extension Builder in Welwyn
One stop service of design, planning and implementation of your home renovation project.
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R sure builder's
No reviews yet
Extension Builder in Welwyn
Areas of Speciality Extensions Property Refurbishments Electrics Carpentry Tiling Plastering Building
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MMA RENOVATIONS LTD
New on MyBuilder
Extension Builder in Welwyn
MMA Renovations Ltd is a leading UK-based construction and property maintenance company offering a complete range of professional services. We specialize in electrical work, including rewiring and extensions, as well as plumbing services like bathroom and kitchen installations, pipe repairs, and more. Our expertise also includes loft conversions, home extensions, full house renovations, flooring, carpentry, painting and decorating, and general building work. Whether you need a small repair or a complete property makeover, we ensure top-quality workmanship, safety, and customer satisfaction. At MMA Renovations Ltd, we pride ourselves on reliable, affordable, and tailored solutions that bring your vision to life.
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Sandhu heating and construction limited
No reviews yet
Extension Builder in Welwyn
All Bulding work undertaken
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JERRY BUILDING LIMITED
No reviews yet
Extension Builder in Welwyn
Dynamic and highly experienced builder whit over 35 years in residential construction. Taking on variety of projects Lofts,Extensions, Renovations from concept to completion. Dedicated to quality in craftsmanship and delivering results to client expectations . Managing projects hands an. Fully insured whit public liability coverage. Reference from clients
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PARM G BUILDERS & CONTRACTORS LIMITED
No reviews yet
Extension Builder in Welwyn
Hi, am parm hope u guys are fine I just want to say I love my work and I love to make people’s happy with my work so give us chance for all type of work extensions bathrooms paints electrics plumbings laminate flooring skirtings doors tiles thank you
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SILVER STONE TRADERS LTD
No reviews yet
Extension Builder in Welwyn
All Building work undertaken, also experts in Kitchen & Bedrooms fitting. Kindest regards
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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.