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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L HEWITT CONSTRUCTION
No reviews yet
Extension Builder in Welwyn Garden City
Welcome to L Hewitt Construction, where we build more than just structures – we build lasting relationships, quality craftsmanship, and sustainable solutions. With a passion for excellence and an unwavering commitment to integrity, we have become a trusted partner in the construction industry, known for delivering exceptional projects on time and within budget. Founded in 2012, L Hewitt construction has grown from a small, family-owned business to a leader in the construction and building sector. Our team is made up of experienced architects, engineers, project managers, and skilled tradespeople who share a common goal: to bring your vision to life with precision and professionalism. We specialize in a wide range of construction services, including: - Custom home extensions - Loft conversions - New builds - Modern renovations We turn your dream home into reality, transforming existing spaces into beautiful, functional areas while preserving the integrity of the original structure. Every project we undertake is approached with a focus on quality, safety, and client satisfaction. We take pride in our attention to detail, working closely with clients to meet expectations at the highest standards. Why Choose Us? Experience & Expertise – With over 22 years in the industry, we bring extensive knowledge and experience to every project. Whether it’s a small renovation or a large project, we offer customized solutions that meet your specific needs. We respect your time and your deadlines, ensuring that projects are completed on schedule. Our rigorous quality control process guarantees that every project meets the highest standards. Contact Us today to discuss how we can bring your vision to life.
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Roman Way
No reviews yet
Extension Builder in Welwyn Garden City
Hard working builder with years of experience.
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Flynn Construction ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are a medium sized Limited Company based in Watford . We specialise in all area's of building - New builds, Refurbishments, Extensions and Paving all welcome. We have a vastly experienced team to cater for all your building needs.
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Latest review:
Extensions- 12 Jun 2020
Gavin project managed the rear story extension on our house from start to finish and was professional and friendly throughout. He was always on hand to offer help and support and we would definitely recommend his services.
R&S construction services
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
I have been for 20 years now in building works i like what i do and i like make other people to have they dream house to make them happy
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Latest review:
Great service received. Called Martin out that day and he fixed my front door straight away. Great price and great service received will be using him again in the future.
Ap Building And landscaping
No reviews yet
Extension Builder in Welwyn Garden City
AP Building And Landscaping provides professional building and maintenance services including. Groundwork’s,Blockpaving,Fencing, Drainage,Brickwork,Extension,Plastering and plumbing carrying out work all to a high standard The company have over 20 years of experience with in a multitude of trades we believe we have the perfect attributes to carry out excellent work and for competitive prices At AP Building And Landscaping we complete every single job to the highest of standards
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ArhiTERRA design and build
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are a family business with a dedicated team specializes in works of any size ranging from the design through to building process. Our experience is vast and we stand for fast and high quality services beeing in construction industry for over 10 years . The following services are available: -design and build of extensions and lofts, -refurbisments, -swimming pools and outdoor spaces -landscape design More details can be found on our website.
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Latest review:
Architecture- 5 May 2018
Contracted to provide options for a new garage office and storage solution. They turned up promptly and were very polite and professional. Through many discussions they ultimately offered up a very good bespoke solution for our situation and once planning is approved we will have no issue with looking to them to complete the actual build. We have had a lot of issues in the past finding reliable trades but with ArhiTERRA design and build we felt confident in their ability to both visualise and implement the build as well as follow through on their promises. I would say that for anyone considering discussing a project with them that it is worth your time to at least have a meeting with them and judge for yourself.
MYCO Contractors Limited
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
I am an experienced and fully insured builder. On average I and my team build and renovate 5 extensions per year. Our current or old clients are always ready to share positive feedback about our work. We work off the ready plans which are usually prepared by the clients themselves and approved by the local authority. As of now (30/03/2023) my availability to start the new project is late April or early May. Please get in touch and I will be happy to assist.
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Latest review:
Extensions- 4 Aug 2020
On a cold November evening, Tony and his team turned up to provide a quote and within a week this was received. The quoted price came in the middle of the pile, which was a good start and aligned closely to the ballpark figure I'd received from a friend who was also in the trade. We then visited a site they were finishing off, and Tony had the confidence to ask us to speak to the client without him there and they gave us the confidence to proceed. They started in January 2020 and rapidly moved through the works and engaged closely with my architect, Structural engineer and building control and proceeded based on their recommendations strictly. We lived in the property as build progressed and the team ensured that the site was secure every evening and we were safe. As COVID-19 hit and we went into Lockdown, the team continued to come and work (we were separated from them as the house was boarded up) and the only challenge was getting supplies. Tony scoured all over London, picking up items as best as he could and work continued. Once they'd broken through into the old part of the house they continued to progress rapidly and showed utter professionalism. The team lead's attention to detail is impressive, and he gave great recommendations on what would be the right approach when we were laying out features such as window sizing and lighting. The standard of work is excellent and I would highly recommend them.
GLJ Construction Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
GLJ Construction Ltd , Building and Brickwork contractors in Hertfordshire since 2012.
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Latest review:
Facing Brickwork to an external terrace area, for a new Law firm. Excellent quality and very professional. All works completed on programme too. I would highly recommend Gavin and his team.
Richard Wilson
No reviews yet
Extension Builder in Welwyn Garden City
I’m an experienced and hands-on builder who takes pride in doing solid, reliable work. I’m confident working on all kinds of jobs—from small repairs to full builds—and I always aim to keep things running smoothly, on time, and to a high standard. I keep things tidy, and I’m not afraid to put in the hard graft to get the job done right.
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Mega Co Group Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Mega Co Group Ltd is a professional brickwork and stonework company delivering high-quality workmanship across all aspects of masonry. We specialise in extensions, garden rooms, summer houses, new builds, and repointing for brick and stone properties. With a reliable and experienced team, we complete projects efficiently, safely, and to a high standard. We take pride in our attention to detail, clear communication, and leaving every site clean and tidy. Customer satisfaction and long-lasting results are at the heart of everything we do.
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Latest review:
Anton is a reliable and hard worker. He worked efficiently and even came back to finish the job properly when my tennant was being disruptive.
Antlers Plumbing
No reviews yet
Extension Builder in Welwyn Garden City
Experienced, friendly and professional plumbing, heating and bathroom specialists from Hertfordshire. Our team of construction workers have experience in interior and exterior building works, with electricians, plumbers and carpenters on hand. No job is too big or too small. Always looking to help the community.
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Vali colour
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Hello my name is Vali , I have been working in the construction industry 20+ years in this time I have run a small business in Italy ,built houses in Romanian and I am currently working in London as a bricklayer .
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Latest review:
Bricklaying- 1 Oct 2019
Excellent work on budget and time
Bujar Vata
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
I am in the building business for 15 years I have worked all around London specially in the City I have registered myself on Mybuilders.com so I can get job around my area.
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Latest review:
Tiling- 7 Jun 2026
Amazing job and a brilliant team of tradespersons. An excellent job of the herringbone tile flooring with underfloor electric heating for the whole of my downstairs. The wall panels also complemented the flooring and were installed perfectly. Well done to Bujar and his team!
AXM Construction (London) Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Hello We are a team which we’re happy to help make your work easy and nicely done. Our first priority is the Client. We try our best to get the job done in the right way, and soon as possible.
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Latest review:
Carpentry- 18 Dec 2024
Excellent work. Finished the job on time. Tidy and neat finishing and reasonably priced.
Abbot's
No reviews yet
Extension Builder in Welwyn Garden City
Hello
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Solis Power Limited
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
As a skilled kitchen and bathroom fitter with 15 years of experience, we bring a wealth of expertise to every project. Our in-depth knowledge of design, layout, and installation ensures exceptional craftsmanship and attention to detail. We excel in managing projects from start to finish, including precise measurements, assembly, and the seamless integration of fixtures, appliances, and finishes. In addition to your fitting expertise, we are a qualified NICEIC electrician, enabling you to handle all electrical installations and connections with full compliance to safety standards and regulations. This comprehensive skill set allows us to provide a seamless, one-stop service, minimizing the need for additional contractors and ensuring every project is completed efficiently and to the highest standard. Known for your reliability, professionalism, and excellent communication with clients, you have built a strong reputation for delivering functional, stylish, and high-quality kitchens and bathrooms tailored to meet your clients’ needs and preferences. Your commitment to perfection transforms spaces into beautiful, practical environments that stand the test of time.
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Latest review:
Kitchen Fitting- 14 Jan 2026
My initial experience with Solis Power Limited was Leo’s immediate response within 30 minutes, visited my property to view my kitchen. He gave a full detailed breakdown of price list that explains each work to be carried out. Suggested materials to use also help with the purchase. Leo and his team are perfect working together, cleaned after themselves each day. They installed new electrical unit, also introduced registered gas man to run gas pipes and also connect the gas hob. Plumbing work was excellent too. Leo also helped with the measurements of splashback and splash splatter guard. The work was carried out within five working days delay was due to shortage of splashback in the store. I highly recommend Leo and his team.

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.