Extension Builders in Welwyn

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.9 (16 reviews)

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Some of our top rated extension builders in Welwyn

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CS Design Services
No reviews yet
Extension Builder in Welwyn
Proffessional consultancy that provides floor plans, elevations etc. to assist with planning and building control applications.
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dealsanio ltd
Rating: 5 out of 5
Extension Builder in Welwyn
With over 15 years of international experience in architecture, construction, and landscaping, I deliver high-quality residential and commercial projects from concept to completion. My expertise includes landscaping, home extensions, repointing, new builds, renovations, and outdoor living spaces. I have successfully completed projects across Singapore, Malaysia, Turkey, and Canada, giving me extensive experience working with a wide range of architectural styles and construction methods. I am particularly experienced in Eastern landscape design, including Japanese gardens, as well as modern and contemporary outdoor spaces. I pride myself on attention to detail, quality craftsmanship, and delivering projects on time and within budget. Whether you need a complete new build, an extension, professional repointing, or a bespoke landscape design, I am committed to providing reliable service and exceptional results.
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MUJA BUILDERS LTD.
No reviews yet
Extension Builder in Welwyn
Muja Builders Ltd. I have over 20 years of experience in the building industry and specialise in all aspects of building All my work is done with pride and delivered to the highest standard possible.
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R4ebb ltd
No reviews yet
Extension Builder in Welwyn
I worked as a builder for 20 years loft ,extension,tiles ,bricks,painting,plumbing,kitchen etc all type of building work I have my team long experience thank you
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Justas Kusak
Rating: 5 out of 5
Extension Builder in Welwyn
I'm a self employed roofer for more than 14 years now. Roofing specialist you can rely on. 10 year Warranty for work. EPDM, GRP, Felt, RESITRIX, Kemperol, lead, slates, tiles, skylights and more...
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Latest review:
Fascias & Soffits- 19 Aug 2019
Very happy with the work Justas did, house looks much tidier with the new fascias and guttering. He arrived on time, quoted a fair price and did a good job. I would happily recommend and hire him again.
Project A Construction Limited
No reviews yet
Extension Builder in Welwyn
Project A covers all aspects of groundwork, extensions, driveways, refurbishments and tiling. Our work is build with experience and reliability.
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Neil Thompson
No reviews yet
Extension Builder in Welwyn
Hi there, I’m Neil, I’ve got 20+ years of experience in the construction industry. I’ve worked all over London and Greater London over the years and travelling to work is not an issue for me. I have an experienced group of people that I work with and who know how to get the job done on time and on budget. From the domestic side of the industry i.e. garden walls, extensions and new builds to the commercial side which includes retail units, office blocks and housing estates, there’s nothing that can’t be built!!! If an architect can draw it, we can build it!!! Thanks for checking out my profile and I look forward to hearing from you soon.
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Mani builder
No reviews yet
Extension Builder in Welwyn
How can I help you I have 4 experience in this field and I love to help you to get your things done . I’ll bring my own tools and am very good in my work.
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Pawanpreet Sibgh
No reviews yet
Extension Builder in Welwyn
Hey Pawanpreet here , i am fully experienced builder in all types of building work such as extension work , fully house rennovation , loft conversion , garden , tiles work , paint and decoration feel free to contact us
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ATB Construction Group Limited
No reviews yet
Extension Builder in Welwyn
Welcome to ATB Construction Group, where expertise and innovation come together in design and construction. Whether you're looking to build your dream home or renovate your living spaces, including outdoor areas, we’re here to guide you every step of the way. Explore our services and discover how we can bring your vision to life.
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Strong Rock Construction Ltd
New on MyBuilder
Extension Builder in Welwyn
Strong Rock Construction Limited We Build Your Dreams. Strong Rock Construction is a reliable and professional building company dedicated to delivering work to the highest standard. From new builds and house extensions to loft conversions, renovations and commercial projects, we bring experience, quality workmanship and attention to detail to every job. We work closely with our customers from the first idea through to completion, making the building process straightforward, professional and stress-free. New Builds • Extensions • Loft Conversions • Renovations • Commercial Projects • All Building Work Undertaken Strong Rock Construction — Building to the Highest Standard.
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Huseco Limited
Rating: 3.7 out of 5
Extension Builder in Welwyn
HUSECO Limited is a well-established family business specialising in domestic renovation and construction projects. Our portfolio of skills also includes architectural design, interior design, and planning, which allows for stylish renovations, extensions, lofts, and modern living spaces. We have a loyal team of highly skilled builders, and the dedicated project manager personally oversees all our projects
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Latest review:
Extensions- 14 Sep 2025
How long should a 3m extension take if drawings were approved in April, the conservatory was demolished, the foundation completed, and the steel structure was already on site by May.?
jc_electrical
Rating: 5 out of 5
Extension Builder in Welwyn
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
Britania Building Services
No reviews yet
Extension Builder in Welwyn
I’m a self employed builder with vast knowledge and experience for over forty years. I’m a multi trade person from construction, renovations, loft conversions and extensions etc. I’m an electrician, plumber, kitchen fitter, tiler and many other trades. My past experiences being, BT Engineer, Coca Cola Engineer, Sound Engineer, BBC sound engineer and few other companies I worked for.
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Nisar Groups
No reviews yet
Extension Builder in Welwyn
Work is done with perfection and with perfect measurements. Experienced labour work under this company. Interior exterior garden front yard backyard bathroom works done ,Electrical work as well
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Blockwork and brickwork
No reviews yet
Extension Builder in Welwyn
Im bricklayer, im doing all brickworks and blockwoks,repointing and repairing jobs.we have many years experience.
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3.9

Top rated Extension Builders

Our Extension Builders in Welwyn, are rated 3.9 out of 5 based on 16 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.