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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David Mario builders
No reviews yet
Extension Builder in Welwyn Garden City
Building Company for all your building needs whether its building to Garden work, Tiling or carpentry. No job too big or small. Get in touch for a quote.
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Reach Perfection
No reviews yet
Extension Builder in Welwyn Garden City
Electrical- painting- bricklayer and most construction work apart from plumbing and generally I am a handy man with 7 years work experience in construction
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Moss plumbing and Electrical
No reviews yet
Extension Builder in Welwyn Garden City
I have experience at all kind of building working 25 years at building industry.I have experience of big project building houses from ground with our group. I am gas enjeneer and electrical enjeneer I have experience of plumbing ,electrical, carpentry bathroom fitting . Kitchen fitting .repair of boiler and electrical fault finding. I can send you my job profile
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A&L Refurbishment UK
No reviews yet
Extension Builder in Welwyn Garden City
Welcome to A&L Refurbishment UK! We specialize in transforming homes across Buckinghamshire, Hertfordshire, and London. From full refurbishments and renovations to extensions and conversions, our team brings your vision to life with quality craftsmanship and attention to detail. Whether you're looking to modernize your space or create more room for your family, A&L Refurbishment UK is here to make your dream home a reality.
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SMBuilding Company Limited
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
20+years experience in construction.Working on all types of jobs;large,small and everything in between.Seasoned in extensions,brickwork,renovations,chimney removal,structural work and development,we ensure an exceptional finish. Competitive rates,we have natural drive to get jobs done. These qualities allow us to set out budgets,and time frames,allowing our clients peace of mind. See our about section,and soon you could be relaxing in the knowledge that your job will be done on time and budget.
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Latest review:
Bricklaying- 4 May 2016
Sean was polite, friendly, efficient, clean, tidy and his work was simply the best, I cannot praise Sean's work highly enough, if you want a great tradesman you can trust and someone will do exactly the job you want and more then hire Sean now. Sean is a rare find mark my words HIRE HIM .....
Danny builer
No reviews yet
Extension Builder in Welwyn Garden City
I’m available for work on new projects
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Halls construction
No reviews yet
Extension Builder in Welwyn Garden City
I'm a builder with 28 years experience. I specialise in extensions and loft conversions. I'm honest and hard working. I take pride in my work and ensure its of a high standard. I'm multi skilled so I'm able to build most aspects of a project myself. That way I can guarantee the quality of the work. Most of my work comes from word of mouth. I get lots of recommendations from previous customers. I'm hoping to increase my workload by advertising here. I've got a large portfolio of work and previous customers that will give good references.
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Home Design & Build
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Tooled with years of experience, we undertake design & reconfiguration of builds; adding value to your home or business. Working closely with you; we create a bespoke, quality finish within your budget & affordability. Delivering a high standard of skill & integrity of craftsmanship we are proud off
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Latest review:
Kitchen Fitting- 24 Jun 2025
Lalli and her team were all very professional, communicative, and detail oriented helping us create a new kitchen and bathroom that we love, not to mention, on schedule! We would highly recommend Home Design and Build and hope to work with then again in the future.
SGB Water Engineering
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
SGB maintain an interactive IT process, to ease transparency and movement of information data, to all parties involved in any one project. We have a combined 25 years professional experience in the civil engineering / construction management. We are experts in water utilities management enabling us to offer a variety of services and solutions in this area.
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Latest review:
Plumbing- 9 Dec 2020
Work completed and problem has been resolved .
Mihai Balanuta
New on MyBuilder
Extension Builder in Welwyn Garden City
Hi, I’m a professional bricklayer with experience in all aspects of brickwork. I specialise in garden walls, extensions, repointing, block paving and new builds. I take pride in delivering high-quality workmanship, always completed to a high standard and on time. I’m reliable, hardworking and easy to communicate with. Customer satisfaction is my priority and I always aim to leave every job clean and tidy. No job too big or small – free, no-obligation quotes
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Carry on laying
No reviews yet
Extension Builder in Welwyn Garden City
My name is John,I’m 43 and live in Watford I have been bricklaying/landscaping for 23 years now. I have a good friendly team of professional tradesmen who are reliable and very hard working Over the years we have been involved various small and large projects,varying from garden works to new builds.we are also lucky enough to have been part of a number of film and media projects 🎥 We love what we do and always compete jobs to a high standard,we take great pride in every job we are lucky enough to be involved in
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LEBELLE HERITAGE & RESTORATION LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Lebelle Heritage & Restoration Lebelle Heritage & Restoration is a professional building and construction company specialising in renovations, refurbishments, and heritage restoration. We take on all types of projects, from full property renovations and structural upgrades to detailed interior finishes and the careful restoration of period features. Our team is skilled in both traditional craftsmanship and modern construction methods, allowing us to deliver work that is reliable, high-quality, and built to last. Whether we’re restoring the character of an older property or breathing new life into a modern home, we focus on precision, honesty, and clear communication throughout every stage of the job. We pride ourselves on delivering clean, efficient, and well-executed work that meets the needs of our clients and respects the integrity of each building. At Lebelle Heritage & Restoration, we build, renovate, refurbish, and restore with a commitment to quality and long-term durability.
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Latest review:
After a previous contractor took our money and left our loft extension unfinished, we were devastated and worried about how we would ever get our home back to normal. Then Lewis from Lebelle stepped in and completely turned things around. Lewis was patient, understanding, and incredibly professional. He worked quickly, kept costs under control, and finished the loft extension to a standard we’re so happy with. The stress he took off our shoulders was unbelievable. We honestly can’t thank Lewis enough. If you’re looking for someone trustworthy, skilled, and genuinely caring, Lebelle is the company to call.
Asen Terziev
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
I have been working in construction since I was 19.I have qualified as external wall insulation,rendering and plastering!Over the years I have undertaken bricklaying and roofing jobs as well!
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Latest review:
Plastering- 7 Oct 2022
Excellent work, very professional.
Apollo Developments Ltd
No reviews yet
Extension Builder in Welwyn Garden City
We cover every aspect of construction. We have over 20 years of experience in the industry. We offer value for money and always take pride in our services.
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Archeus Ltd
No reviews yet
Extension Builder in Welwyn Garden City
Over twenty five years experience in the construction industry. We take pride in providing a high quality service with a keen focus on customer care. We provide detailed quotations and staged payment plans to ensure complete visibility from inception to completion. We won't always be the cheapest but we always strive to be the best.
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H-Build Limited
No reviews yet
Extension Builder in Welwyn Garden City
After 20 years experience working for large contractors and developers; H-Build Ltd, has been formed to focus our experience and expertise in residential construction to work on smaller but more rewarding projects for individual clients/homeowners.
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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.

Quality screening

Easily find verified local tradespeople. Just post your job to get quotes from tradespeople near you across the UK.

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.