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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ABS 23 Ltd
No reviews yet
Extension Builder in Welwyn Garden City
we are working in the industry for the last 15 years we provide every type of building works
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R rose builders ltd
No reviews yet
Extension Builder in Welwyn Garden City
We are a family run business with a great work ethic and always happy to help or advise. We have been in the building industry over 15 years with another venture in waste removal. We cover the whole of the uk with our services with anything from renovations to new builds, house clearances to demolitions and much more We are always competitively priced and always leave a tidy finish. Please get in touch for a no obligation free quote. Look forward to hearing from you
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ATB Construction Group Limited
No reviews yet
Extension Builder in Welwyn Garden City
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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Rc builders
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Family run company with 20+ years experience using time served and fully qualified tradesmen Finishing to a high standard regardless of your budget. All work fully guaranteed
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Latest review:
Restoration & Refurbishment- 30 Apr 2026
Job was completed quickly and to a great standard. Reasonably priced and we would definatley use them ahain
Fm building contractors ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
FM Building Contractors Ltd is London based builders HOME EXTENSIONS PROFESSIONAL BUILDING & BRICKWORK SERVICES Providing a range of building services from walls and block paving, extensions and conversions to complete new builds, we only work with highly trusted and experienced tradesmen registered with the appropriate bodies. FM Building Contractors Ltd is proud to have earned a reputation for fast and efficient turnaround, reliability, transparency and professionalism.
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Latest review:
Groundwork & Foundations- 19 Jul 2024
Great job very efficient will consider for further larger projects
Jpsingh
No reviews yet
Extension Builder in Welwyn Garden City
Good price good quality
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Blockwork and brickwork
No reviews yet
Extension Builder in Welwyn Garden City
Im bricklayer, im doing all brickworks and blockwoks,repointing and repairing jobs.we have many years experience.
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Raffa Constaction Ltd
No reviews yet
Extension Builder in Welwyn Garden City
We are a company with experience over 35years very professional with experience work and large portfolio. We are offering best services, best price and highest quality of work.
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Deep builders
No reviews yet
Extension Builder in Welwyn Garden City
Hi, my name is Deep, and I’m the founder of Deep Builders. With over 10 years of experience in the construction industry, I specialize in all types of building work, including: • Home Extensions • Loft Conversions • Full Renovations • General Building and Maintenance At Deep Builders, we pride ourselves on delivering high-quality workmanship, clear communication, and reliable service from start to finish—no shortcuts, no surprises. I’m a professional builder with extensive experience in all types of building work, including home extensions, loft conversions, full renovations, and general construction. I’m dedicated to delivering high-quality craftsmanship, reliable service, and results that truly transform homes. We proudly serve clients across London, Manchester, Luton, and surrounding areas, helping homeowners bring their vision to life—whether it’s expanding space, updating interiors, or transforming a property from the ground up.
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Sokhalconstructionltd
No reviews yet
Extension Builder in Welwyn Garden City
My name Parwinder Singh & my company name Sokhalconstructionltd i carry out wide range of building work including extension renovations general i am provements new build .loft conversion.i have (how many years of experience) i am fully insured and experience in coordinatings projects from start to finish. My aim is to keep the process clear organised and hassle free my approach is simple realistic time scale transparent pricing I am happy to discuss your plans and provide a free no obligation quotation
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k+c studio
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
udrtzurtszesrtz
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Latest review:
CAD / Drawings- 5 Dec 2021
So far so good very helpful and would use her again very professional
S j Webb & co limited
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
S J Webb & Co Ltd has been operating since 1977 and is a family run third generation builder. We are NHBC registered and have a combined experience of over 100+ years in the Building Industry. We have built large flat developments in Braintree & Walton-the-Naze ,we built 70 Houses for the MOD & houses in Chelmsford ,Leigh-on-Sea,South Benfleet ,Canvey Island & Greater London.We also vet and review our sub- contractors to ensure our high standards are met and delivered to our Clients
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Latest review:
Decking- 8 Aug 2019
Fast, efficient, problem solving Steve. Would definitely recommend.
Equity Eco Services
No reviews yet
Extension Builder in Welwyn Garden City
In the world of construction and bespoke carpentry, experience isn’t just an asset—it’s the foundation upon which lasting quality is built. For over three decades, Richard Parker has exemplified this principle, bringing his passion, skill, and unwavering commitment to every project he undertakes. As a master carpenter and general builder, Richard’s career is a testament to the value of traditional craftsmanship, steady innovation, and the importance of family legacy.Comprehensive Services: Carpentry, Joinery, and General Building Richard Parker offers a comprehensive range of services that cover every aspect of domestic and light commercial construction: Bespoke Carpentry: From custom shelving and wardrobes to hand-crafted staircases, doors, and windows, Richard creates pieces that are both beautiful and built to last. Joinery: Precision joinery for both structural and decorative purposes, including timber framing, roof structures, and intricate moldings. Extensions and Renovations: Complete home extensions, loft conversions, and property refurbishments that enhance both space and value. Kitchen and Bathroom Installations: End-to-end service for modernizing and upgrading the most important rooms in your home.
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Cosmin Badulescu
No reviews yet
Extension Builder in Welwyn Garden City
Hello, Very skilful worker with over 14 years of experience in construction. Various skills and well organized.
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Strongwell Construction LTD
No reviews yet
Extension Builder in Welwyn Garden City
We are an experienced family-run construction team specialising in extensions, renovations, and new builds. With years of hands-on expertise, we pride ourselves on delivering high-quality workmanship, attention to detail, and excellent customer service. From the first consultation to the final touches, we work closely with our clients to ensure every project is completed on time, on budget, and to the highest standards. No job is too big or too small — your satisfaction is our top priority.
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Optimal Builders limited
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
16 Years of experience, specialised in Extensions, Lofts and house refurbishments. We are focus on Client's satisfaction, value engineering and transparency. We use only inhouse teams with dedicated Project Managers, Quantity surveyors and estimators. Flexible and compromisers when it's necessary.
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Latest review:
Extensions- 16 Oct 2020
Amazing builder! Completed a rear extension for our house, very skillful team, friendly and fair price. Would highly recommend Optimal Builders for small and big property improvements.

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.

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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.