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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Sterling Developments Group Ltd
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Extension Builder in Welwyn Garden City
provides professional property maintenance, repairs, renovations and building services across London. We specialise in plastering and skimming, delivering smooth, high-quality finishes for walls and ceilings. We also provide painting & decorating, general property repairs, carpentry, flooring, tiling, kitchen and bathroom refurbishments, as well as all types of day-to-day maintenance work. Alongside smaller jobs, we undertake house extensions, loft conversions, structural alterations, garden room construction and full property refurbishments, working to a high standard from start to finish. Whether you need a minor repair, a single room redecorated or a complete renovation, no job is too big or too small. We pride ourselves on quality workmanship, attention to detail, honest pricing and clear communication, ensuring every project is completed to the highest standard and every customer is completely satisfied.
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Option group
No reviews yet
Extension Builder in Welwyn Garden City
London Essex based sole trader NVQ3 certified
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Myc construction ltd
No reviews yet
Extension Builder in Welwyn Garden City
Services I Offer: Home Extensions Loft Conversions General DIY Projects Bathroom Fitting Kitchen Installation Plasterboard Plastering Laminate Flooring Feel free to contact me for a consultation or to discuss your project needs!
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RDB Contractors Ltd
No reviews yet
Extension Builder in Welwyn Garden City
we use to do any dry-lining partitions, metsec works, loft conversions, extensions, carpentry works, tiling, suspended ceilings. We have about 10 years experience. we also do roofing works in fibre glass.
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London Decorations and Refurbishment Ltd
Rating: 4 out of 5
Extension Builder in Welwyn Garden City
London Decorations and Refurbishment Ltd Building Better Homes Across London ABOUT US At London Decorations & Renovations Ltd, we specialise in high-quality home improvements designed to transform properties into modern, functional, and beautiful living spaces. With experience across residential construction, extensions, refurbishments, and bespoke renovations, we deliver projects with professionalism, transparency, and attention to detail from start to finish. Whether you are planning a house extension, full refurbishment, loft conversion, or interior upgrade, our team is committed to providing reliable workmanship and exceptional customer service.
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Latest review:
Carpentry- 15 Jul 2026
The builder left some jobs not completed and he not answering my call, also he costed my some money because a misunderstanding the order, he finished 90% of the work. So l need to finish the remaining staff and add extra job to do.
LG Construction & Design UK
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
LG Construction & Design Uk is a family business in London.We pride ourselves on high quality workmanship and customer satisfaction.We believe in keeping the customer happy and providing them a great service and high quality with competitive price. LG Construction £ Design UK - Building your dream
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Latest review:
Extensions- 13 Jun 2020
Carlos and Luzianna did our kitchen extension in 2017 and we were very pleased with the quality of the work they did. We hired them again in 2019 to redo our living room and front garden. Again we were pleased with the result. In both cases we were living in the house during the construction and they did everything they could to be considerate and clean. We would definitely recommend them.
Ows construction ltd
No reviews yet
Extension Builder in Welwyn Garden City
OWS Construction specialises in a broad range of groundwork and civil engineering services. We handle essential preparatory and foundational tasks for various construction projects, ensuring infrastructure is properly laid out before the main build takes place. Their scope includes: Car parks: Constructing and preparing parking areas. Curbing: Installing curbs and edges for roads or pathways. Drainage: Designing and installing systems for effective water drainage. Utilities: Installing essential services like water, gas, and electricity lines. Concrete: Pouring and setting concrete for foundations, pavements, or other structures. Roads and sewers: Constructing and maintaining road networks and sewer systems. Footings and formwork: Laying the Laying the foundational supports and molds for concrete pours. Steelwork: Installing steel reinforcements for structures. Shuttering: Creating temporary molds for poured concrete. General developer work: Other tasks required by developers to prepare sites for building projects.
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D.s.m city construction ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Welcome to DSM city construction Ltd . DSM city construction Ltd is a leading construction company specialising in residential/commercial/industrial projects, with a reputation for delivering high-quality craftsmanship and innovative solutions. Founded in 2019, we have grown to become a trusted name in the industry, serving clients across London. Our mission is to create enduring, high-value spaces that enhance communities and exceed our clients' expectations. Services: • NEW BUILD HOUSE •LOFT CONVERSION •HOUSE EXTENSION •BEAUTIFUL BATHROOM •STUNNING KITCHEN At DSM City construction Ltd , we offer a comprehensive range of construction services tailored to meet the diverse needs of our clients. These include: General Contracting: Overseeing projects from start to finish with a focus on timeliness, budget adherence, and quality. Design and Build: Providing end-to-end design and construction services to bring your vision to life. Renovations and Remodeling: Modernizing existing spaces with expert renovation and remodeling solutions. Commercial Development: Expertise in creating large-scale commercial spaces that align with business needs and objectives. Project Management: Delivering efficient project management services to ensure seamless coordination and execution. Sustainable Building Solutions: Incorporating eco-friendly practices and materials for energy-efficient and sustainable structures. Our Mission: Our mission is to transform spaces through superior construction that combines cutting-edge techniques, skilled craftsmanship, and a commitment to sustainability. We believe in building lasting relationships with our clients, based on trust, integrity, and exceptional results. Why Choose Us: Experience and Expertise: With over 14 years in the industry, our team brings unparalleled experience to every project. Quality Craftsmanship: We are dedicated to delivering projects that stand the test of time, with a focus on quality materials and attention to detail. Client-Centered Approach: We collaborate closely with our clients to ensure their needs and visions are met at every stage of the project. Sustainability: We integrate sustainable building practices into our projects to reduce environmental impact and promote energy efficiency. Timely Delivery: Our well-established processes ensure projects are completed on time and within budget, without compromising on quality. Our Team: Our team consists of highly skilled professionals including architects, engineers, project managers, and craftsmen, all working together to ensure each project is completed to the highest standards. We invest in ongoing training and development to stay ahead of industry trends and innovations. Whether you're looking to build, renovate, or manage a large-scale construction project, DSM City construction ltd. is here to provide expert services tailored to your needs. Contact us today to discuss your next project and how we can bring your vision to life.
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Latest review:
Start to finish was very smooth for full bathroom renovation all the wall and house and carpet was fully covered until end and leave the house cleaned and hovered everyday happy with results
LONDAMEXP
No reviews yet
Extension Builder in Welwyn Garden City
Established by industry experts, LONDAMEXP Construction is a London based home refurbishment business. LONDAMEXP Construction combines more than a decade of experience and expertise to provide commendable refurbishment services. We have been in service since the past 15 years in the UK and NL!
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MEK BUILDERS LTD
No reviews yet
Extension Builder in Welwyn Garden City
hi
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VNG Interiors LTD
No reviews yet
Extension Builder in Welwyn Garden City
🏠 VNG Interiors LTD - Transforming Visions to Reality 🏠 We specialise in residential & commercial construction, renovations, extensions, & structural repairs. Our commitment to quality, transparent communication, & competitive pricing sets us apart. Your dream project starts here!
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Maxcontractorsint.LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
At MaxContractors , we pride ourselves in providing our customers with quality construction services that are tailored to their needs. Our team is highly experienced in the industry and have a great deal of knowledge when it comes to building and renovation. We pay attention to detail and are always willing to go the extra mile to ensure that the job is done to the highest standard. Over the past many years our company has thrived within the domestic as well as commercial building industry. With vast amounts of staff specialising in all areas of the trade, our tradesmen/women boast skill and determination many could only wish of. Having completed thousands of projects, putting smiles on countless of faces we aim to deliver the highest of standards in all aspects of the works and services. Providing quality and great time management throughout each step of this journey. We stand strong beside our clients providing a helping hand so ideas become reality, all while with a peace of mind you kick back and watch your future grow. maxcontractorsint. com
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Latest review:
We recently completed a first and second floor renovation alongside an 5x6m extension of our 1930s property with Maxcontractorsint.ltd , and we couldn’t be happier with the results. From start to finish, they have been absolutely fantastic. The attention to detail and the quality of workmanship throughout the project has been exceptional. Matt and his team are incredible, they worked efficiently, kept work on track, and made sure we were updated and involved at every stage. Their skills, ideas, and collaborative approach truly brought the whole project together. Communication throughout the project was good, and the team provided great pre and post project support. Matt was very detail-oriented, offered inspiration during site visits, and was supportive of our requests along the way. We’re so happy with the end result and would absolutely recommend Maxcontractorsint.ltd for any project.
Rizwan Latif
No reviews yet
Extension Builder in Welwyn Garden City
Hi, I’m a friendly and reliable painter and decorator with plenty of experience working on homes. I take pride in providing a clean, high-quality finish and making sure every customer is happy with the result. From walls, ceilings, and woodwork to full room makeovers, I always work carefully and with attention to detail. I’m tidy, respectful, and treat every home as if it were my own. Whether you already have paint or need advice on products and colours, I’m happy to help and make sure the job is done to a great standard from start to finish
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Naksh construction ltd
Rating: 4.4 out of 5
Extension Builder in Welwyn Garden City
We are a highly skilled, competent, and professional team of builders at Naksh Construction Ltd. We offer all the building services you could require, including additions, new construction, basement conversions, new residential or commercial construction and renovations of your existing bathrooms, kitchens and residences. Not only do we complete this task quickly and professionally, but we also take care to ensure that every job we complete is sophisticated, elegant, and meets your demands and specifications."
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Latest review:
Extensions- 7 Apr 2025
Quotes were provided and the job was agreed upon. The project involved a full house restructuring and extension build. However, after several stages of work, communication with Jas was lost, and his co-worker took the lead on site. Several issues arose, such as recommending smart plumbing equipment for purchase, but their plumbers were unable to install it. The tiling, skirtings, and tiles were not completed. Tiles around the columns were cracked. After Jas's team abandoned the project, another plumber had to install all the remaining items. The job was left unfinished, and we had to find alternative contractors to complete it. Significant time and money were wasted due to persistent communication problems, failure to issue invoices, and numerous other issues. Eventually, Jas and his main labourer stopped responding and disappeared, ignoring phone calls and WhatsApp messages. Be aware of these potential issues.
J.Miles Building
No reviews yet
Extension Builder in Welwyn Garden City
General builder. Level 3 qualified bricklayer. .Extensions .Chimney refurbishments .Guttering .Fascias .Soffits .Driveways .Brick wall repairs .Knock throughs .Roofing
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Basrilala
No reviews yet
Extension Builder in Welwyn Garden City
B LALA CONSTRUCTION LTD is a professional construction company serving London and surrounding areas. We provide high-quality building and renovation services, including extensions, loft conversions, full refurbishments, roofing, plastering, painting & decorating, flooring, kitchens, bathrooms and general building work. We are committed to quality workmanship, reliability and customer satisfaction. From small improvements to complete property renovations, we work closely with our clients to deliver excellent results.
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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.