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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GQ building services ltd
No reviews yet
Extension Builder in Welwyn
I have been working in building for 16 years I was a carpenter working in the luxury west end property developer. I have run my own team since 2010. I have taken projects worth £500k in the past. I have a great team and good customer service skills.
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STONE SA LIMITED
No reviews yet
Extension Builder in Welwyn
Stone Sa Construction can give you the help and essential advice needed to optimize the space and construction of your building project, but also provide a quality of service.
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Toni
No reviews yet
Extension Builder in Welwyn
We are a London-based construction company delivering high-quality building solutions across the capital and beyond. Specialising in residential and commercial projects, we provide reliable, end-to-end services—from planning and groundwork to final completion. Our focus is simple: quality workmanship, clear communication, and projects delivered on time and within budget. While we are proudly based in London, we also undertake projects across the UK, bringing the same level of professionalism and attention to detail wherever we work. Whether you’re planning a new build, renovation, or extension, we work closely with you to turn your vision into reality.
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CM Fixing Limited
Rating: 5 out of 5
Extension Builder in Welwyn
Façade & Cladding * Façade installation across a wide range of systems and materials * High-performance rainscreen cladding systems * GRC (Glass Reinforced Concrete) façades * Metal panel façades * Terracotta rainscreen systems * Curtain walling systems * Shopfronts and glazed façades * Atriums * Canopies * Louvres and ventilation systems * Privacy screens * External façade paint refurbishment * Mastic and façade sealing works Curtain Walling Installation of curtain walling systems, including: * Schüco * ALUK * Metal Technology * Smart Systems * Jansen * Single and double-glazed curtain walling systems * Structural glazing * Structural silicone glazing Windows & Doors Supply and installation of: * Aluminium windows and doors * Steel windows and doors * PVCu windows and doors * Timber doors * Composite doors * Commercial and residential entrance doors * Glazed doors and screens * Shopfront doors and systems Glass Supply & Installation * Single and double glazing * Replacement glass * Structural glazing * Safety and toughened glass * Laminated glass * Insulating glass units (IGUs) * Glass for windows, doors, curtain walling and shopfronts Internal & Specialist Glazing * Internal glazed partitioning * Internal partitioning systems * Structural glazing * Suspended ceilings * Glazed screens and internal doors * Glass replacement and remedial works Door Automation Supply, installation, servicing and maintenance of automated door systems, including: * Automatic sliding doors * Automatic swing doors * Entrance automation systems * Door operators and controls * Sensors and associated hardware
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Latest review:
Windows & Doors (uPVC & Metal)- 8 Sep 2026
Responded quickly to the job request and came same day. Did the work at the the estimate rate and did a professional and tidy job with no miss and minimal fuss. Would recommend.
LPB Land Developments Ltd
No reviews yet
Extension Builder in Welwyn
We have been in the construction business for more than 25 years ranging from general building works to new build developments. We have also refurbished large buildings in the London areas on behalf of clients and main contractors.
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sbg services
Rating: 5 out of 5
Extension Builder in Welwyn
I am safety conscious and able to fully concentrate on tasks. I like to keep my work zone in a clean condition and I’m trying to unfold my activity in a good organized steps.
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Latest review:
Groundwork & Foundations- 7 Nov 2024
From start to finish, Bogdan and his team were exceptional. After dealing with a previous builder who caused numerous delays, I found SBG Services. Bogdan came by the same day to assess the job and impressed me with his extensive knowledge. Given my tight schedule, he got to work immediately. I’ve never seen a builder work as hard as his team; they labored tirelessly from morning to night to ensure the project was completed promptly without compromising quality. Every trade I've had since has commented on their attention to detail. In just three weeks, they completed two extensions and transformed my garden. I will definitely be calling Bogdan back to handle my front garden early next spring.
Real Hammer
No reviews yet
Extension Builder in Welwyn
We offer a full range of services for the construction of lofts and extensions.
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Lowdens all trades
No reviews yet
Extension Builder in Welwyn
With over 40 years in the building trade from house building, extension, roofing , outbuildings , plumbing, bathrooms, kitchens , fitted wardrobes, . I have a wide knowledge of most trades , with a great contact base with tradesman’s for jobs needing certification (for example gas , electrical) worked 10 years emergency call-out plumber Some pictures are of a house I built in 2010 then extended 2019
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Alpha Construction & Development Group Ltd
Rating: 5 out of 5
Extension Builder in Welwyn
Alpha Construction & Development Group Ltd offer bespoke service with a focus on the needs of our customers. We deliver one project at a time, without delays and stress-free. From small to big projects, we strive for the highest quality of work. We specialise in but are not limited to new builds, extensions, lofts conversions, structural works, roofing, plastering, rendering, painting and decorating, renovations, kitchen and bathroom fittings, pavings, brickwork, plumbing, full refurbishments.
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Latest review:
Bathroom Fitting- 25 Feb 2022
This was the best experience I have ever had with a team of builders. Aldo and Leo were polite, organised and their workmanship is of a very high standard. They replaced the bathroom in our rental flat, and it looks really smart. They also refurbished the kitchen, replacing flooring and decorated the whole flat. We have just shown it to an estate agent as we are planning to sell it and they were very impressed. Aldo was very helpful in making suggestions of small changes that would save us money and delivered the project on time and right on budget. Would recommend them and will certainly use them again.
Acro design and build
No reviews yet
Extension Builder in Welwyn
Hi we are new to my builder but certainly not new to the building trade, we have a good team of tradesmen working together for over 20 years,we thrive to achieve and deliver the best possible project for our customers at very reasonable rates.we have experience in all aspects of building commercial and residential and many satisfied customers,please take a look at some of our previous projects not only to see the quality of our works but the scale we can build on Many Thanks John Duncan
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Pepeian
New on MyBuilder
Extension Builder in Welwyn
Roofing Loft Conversion Extension
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Keiths electrical services
No reviews yet
Extension Builder in Welwyn
50 years guiding experience
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JS Construction & Property Maintenance Ltd
Rating: 5 out of 5
Extension Builder in Welwyn
We have over 20 years of experience in the building, construction and property maintenance industry. Whatever your building needs maybe, we can provide support starting from initial consultation, drafting your plan, finalising budgets, designing, building and aftercare support.It’s all about headache-free work .References are available on request .we would always invite you to visit a property we have or are working on so you can view our workmanship. We have excellent reviews on Check a Trade .
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Latest review:
Extensions- 13 Apr 2023
Jas and his team were fantastic and completed the initial build in a wonderful timeframe. Highly recommend Jas.
ARJD BRICKWORKS LTD
No reviews yet
Extension Builder in Welwyn
Trusted & Skilled Bricklayer I provide bricklaying, masonry, wall building and repair services. All work is safe, accurate and finished on time. I offer reasonable rates and guarantee my work. I am based in Bedfordshire and ready to help with your project.
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H M Renovations LTD
No reviews yet
Extension Builder in Welwyn
We are a professional construction and renovation team based in the UK, operating under HM Renovations Ltd. Our team includes experienced electricians, plumbers, carpenters, and builders, allowing us to handle a wide range of residential and commercial projects from start to finish. We specialise in: Full property renovations and refurbishments Shop fitting and bespoke counter installations Bathroom and kitchen installations Plumbing, electrical, and carpentry work General building and maintenance We pride ourselves on high-quality workmanship, reliable service, and clear communication throughout every project. Fully insured and committed to customer satisfaction.
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Mag Design & Build
No reviews yet
Extension Builder in Welwyn
At Mag Design & Build we pride ourselves on quality of work and the finished job. We take on all building work. Free quotes and easy option payment plans make the process simple and easy to work with.
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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.

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?

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.