Extension Builders in Welwyn Garden City

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 Garden City

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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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grantconstruction0
New on MyBuilder
Extension Builder in Welwyn Garden City
The construction company carries out and performs a full range of complex interior finishing works, general contracting for the repair and reconstruction of buildings and premises in commercial areas. The main direction in which the company operates is commercial real estate: shopping, entertainment and office centers, factories, hotels, logistics complexes and scattered throughout London will undertake any repair and restoration work. We use only high-quality materials and tools to ensure the highest quality of work, in addition, we always adhere to the agreed deadlines and budget, which allows our clients to be confident that the repair work will be completed on time and without unnecessary costs
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Danny builer
No reviews yet
Extension Builder in Welwyn Garden City
I’m available for work on new projects
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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.
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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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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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.
Omran
New on MyBuilder
Extension Builder in Welwyn Garden City
With years of hands-on site experience, I specialise in all aspects of first and second fix carpentry from timber framing, roofing, and stud walls to doors, skirting, and precision interior finishings. I take pride in clean workmanship, accurate measurements, and delivering durable results that stand the test of time. Reliable, efficient, and dedicated to getting every detail right on the first pass.
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Mihai Balanuta
No reviews yet
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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AA UK Building Services Limited
No reviews yet
Extension Builder in Welwyn Garden City
We are experienced qualified builders with over 16 years experience in construction, electrical and plumbing services. Offering an extensive range of services to meet all your needs at a high level of quality and at competitive prices. We offer no obligation quotes and advice for all your building needs.
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SZG BUILDING LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
18years of experience in the construction sector. I may only offer you quality services and nothing less, with SZG BUILDING LTD you will not have to worry about anything. I specialise in every stage of the construction process, right from the very beginning till the very end, in other words from FOUNDATION to DECORATION in the blink of an eye. I will be very pleased to show my previous work, it may be the final outcome or different stages of various projects. References may be provided.
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Latest review:
Kitchen Fitting- 20 Jun 2019
Really pleased with Slawek and his team and would defiantly recommend them after seeing a professional kitchen fit job which they did for me. They went extra mile to resolve some design issues during the fit, kept the work area clean and tidy and behaved in friendly, polite manner. Nice, reliable team charging very reasonable prices.
Ictinus Contractors
Rating: 4.9 out of 5
Extension Builder in Welwyn Garden City
Ictinus Contractors is a reliable London-based building and renovation team, delivering high-quality workmanship across residential and selected commercial projects. We specialise in painting and decorating, wallpapering, plastering and skimming, hard flooring installation, bathroom fitting, and general property improvements. We take pride in providing clean, well-organised work with strong attention to detail from start to finish. Whether the job is a single-room refresh, a bathroom upgrade, new flooring, or wider renovation work, our focus is always the same: quality finishes, honest communication, and dependable service. Based in East London, we cover surrounding areas across London and work closely with every client to make sure each project is completed to a high standard, on time, and with care.
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Latest review:
Painting & Decorating- 6 Apr 2026
I had a very positive experience working with Konstantinos. He is personable, reliable, professional and excellent at co-operating throughout the process. He repainted my entire flat/walls/ceilings to a high standard (and sanded down) he also helped address a few additional repairs along the way. The finish is clean, fresh, and has completely transformed the space. He was thorough and ensured everything was completed properly and on time. I particularly appreciated his attention to detail and his proactive approach in taking care of things I hadn’t even noticed. I would happily recommend Konstantinos and would work with him again in the future! Thank you
OWA CONSTRUCTION LTD
Rating: 4.9 out of 5
Extension Builder in Welwyn Garden City
We are a medium sized groundwork company based in West London. We have over 18 years groundwork experience. We specialise in Drainage , Basements Reinforced concrete, Foundations, Block and beam , Paving , Fencing Etc . We pride ourselves in our work and customer satisfaction is our top priority.
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Latest review:
Groundwork & Foundations- 7 Feb 2026
Oli carried out the groundworks and demolition at my property and was on site every day with his crew, fully committed and hands-on throughout the job. I am an architect, and this was work on my own home, so my expectations were high. Oli met those expectations fully. He has a strong knowledge of groundworks and demolition, works carefully and methodically, and you can tell he genuinely enjoys what he does and takes real satisfaction in delivering the work exactly as required. He was always in a good mood, easy to communicate with, and a pleasure to have on site. I enjoyed discussing the project and hearing about other jobs he has completed over his 23 years of experience, which clearly shows in the quality of his work. I would highly recommend Oli for any groundworks or demolition works.
Yida Design and Construction Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Yida Construction is a limited company based in Central London. We are a very reliable and professional team of tradesmen with over 10 years of experience in the building industry, committed to delivering the highest levels of quality and service to our clients.
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Latest review:
Restoration & Refurbishment- 26 Jun 2022
Tommy was a wonderful perfectionist and has done beautiful work in our stairway and hallway which had needed refurbishment for a very long time. It feels brand new. The flooring is perfect both in the hall and staircase, and the walls are now perfectly smooth and painted immaculately. Friendly and accommodating, we will be hiring again for more jobs in the future, undoubtedly. Thank you.
Quality Build Ltd
No reviews yet
Extension Builder in Welwyn Garden City
I am a professional builder with 20 years experience, I specialise in loft conversions and extensions. I have a full team providing customers with a high quality finish every time. I have plenty of references and photos of previous projects if required.
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Golden Construction 2007 Ltd
No reviews yet
Extension Builder in Welwyn Garden City
I am a highly skilled construction worker with excellent communication skills having over 30 years’ experience in the construction industry including costs estimations, surveys, site inspections, ground work, building, mechanical, carpentry, joinery. I also have good working knowledge of plumbing & electrical.
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3.9

Top rated Extension Builders

Our Extension Builders in Welwyn Garden City, 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 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.