Extension builders in Welwyn Garden City

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.6 (18 reviews)

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Some of our top rated extension builders in Welwyn Garden City

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Painter
No reviews yet
Extension Builder in Welwyn Garden City
I’m painter for 20 years
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Bogdan Dunca
No reviews yet
Extension Builder in Welwyn Garden City
Hi, I’m Bogdan, I on this country for over 15 years, I worked on must of aspects of buildings. I have knowledge in all building and maintenance work, from interiors to landscaping, I will provide high standards of work and outstanding quality. No jobs to big or to small, glad to help.
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Yurii Patrash
No reviews yet
Extension Builder in Welwyn Garden City
Experienced Bricklayer with a Strong Work Ethic I am a professional bricklayer with over 8 years of experience in the construction industry. I specialize in laying bricks, building stone structures, and restoration work. My experience covers a wide range of services, from constructing foundations to building walls, fences, and decorative elements. I ensure every project is executed with great attention to detail and the highest quality standards. Key skills include: • Accurate brick and stone laying; • Building strong foundations, walls, and partitions; • Working with a variety of materials: natural stone, clinker, concrete; • Reading and working from technical drawings and plans; • Handling both large-scale projects and small repairs. I am committed to delivering the best results for my clients: the precision, quality, and durability of my work is my pride. I guarantee top-quality work and timely project completion. Ready to assist with any bricklaying needs in London and surrounding areas!
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Arisha services ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
I am gas safe register by qualification, and undertake most of heating and plumbing jobs. Which can be megaflo, new installation of boilers and repairs. I have skills to lay any type of floorings. I have been in the trade over 6 years and take on extention, conversions of lofts, renovations, bathroom, kitchens, tilling, skimming, painting. I can do decking, polycarbonated sheets, glassfiber roofs, sheds, screeding, concreting. I would cover most of building work.
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Latest review:
Good manners and workmanship I will definitely use your services again Thanks Man
Peter Build
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We offer professional service for all your local building requirements. With our team of professionals no job is too small or too big to handle. From Small Brickwork jobs to large extension work, we can do it. Our team of professionals have years of experience and know-how to carry out all jobs to the highest quality without charging extortionate prices.We are a small friendly local Builders with over 20 years experience!
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Latest review:
Bathroom Fitting- 5 Nov 2019
I met up with Peter, told him what needed doing and he provided a detailed quote within days. I handed over a set off keys and basically left him and his team to get on with it! This was a time restricted job, he purchased all the material and provided all the receipts. I returned a week later to find the job completed to the highest standard surpassing my expectations. I will definitely be working with Peter again in the future and I would highly recommend him.
Badmoore Brickwork
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are a small team of bricklayers with over 25 years experience working in the construction industry in and around Cambridgeshire and Hertfordshire. Our aim is to provide our clients with an outstanding level of service and an exceptional quality of workmanship. We pride ourselves on our reputation and ability to get the job right first time.
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Latest review:
Bricklaying- 28 Feb 2021
Brilliant job by Craig - he had to correct poor work done by my previous builder, and i wish i had hired Craig straightaway........ work was done to a superb standard, and all finished very neatly, and measured properly so windows and doors fitted as they should. All mess was cleared up and left tidy, and they even left my mixer cleaner than when they arrived. Would certainly recommend, and will get them back if i need anymore brickwork, groundwork, patio, drive etc doing. Keep up the good work!!
GARDEN AND BUILDING SERVICES LIMITED
No reviews yet
Extension Builder in Welwyn Garden City
We are a reputable company specializing in all aspects of home improvement, including flooring, construction, gardens, electrical work, plumbing, ceilings, and painting. We hope to meet your expectations.
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bifold and sliding doors
No reviews yet
Extension Builder in Welwyn Garden City
We supply and install a wide range of Premium Glazing Solutions, bespoke to your requirements. Our products include Skylights, Sliding Doors, Bi-Folding Doors, French Doors and Aluminium Heritage Glazing. When working with us you may expect a friendly attitude combined with professionalism as well as an innovative approach towards your goals. Your final satisfaction is at paramount importance to us.
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Olive Rose Contractors Ltd.
No reviews yet
Extension Builder in Welwyn Garden City
We are two local building firms from London/Essex that merged in 2022 to create OLIVE ROSE CONTRACTORS. We undertake all renovation/building works, including lofts, extensions and conversions. We have tradesman for all services, i.e. electricians, roofers, plumbers. We also provide rubbish clearance services.
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The Bellevue Interiors Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Recently joined - skilled competent traders with over 20 yr on site experience Professional clean on time. Happy to help with any of your projects: NEW BUILD, RENOVATIONS, EXTENSIONS, LOFT CONVERSIONS, KITCHEN, BATHROOMS, OUTBUILDINGS, CEILINGs, WALLS, FLOORS, DOOR ASSEMBLY, FLOOR LAYING, ELECTRICAL & PLUMBING INSTALLATION, BUILD IN WARDROBES, PLASTERING, PAINTING AND DECORATING, SHOP FITTING - design supply and install. Don't hesitate to ask if any questions.
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Latest review:
Conversions - General- 22 Jan 2022
Rumen and team did a fantastic job of converting our concrete slab garage into a very modern and posh office space well within our budget. If you see before and after pictures - the transformation is unbelievable. They were incredibly friendly and very patient listening, understanding and building on our requirements. I would highly recommend Rumen and his team from Bellevue Interiors.
DJR Construction
No reviews yet
Extension Builder in Welwyn Garden City
DJR Construction- What we do Building works such as concrete and slab bases, patios, steps, fencing, gate work, brickwork, porches, conservatories, extensions, driveways and gardening. Erecting and dismantling sheds, summer houses, log cabins and playhouses. Site preparation- dismantling and removal of old buildings, asbestos disposal, ground clearance and base works
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VHP construction limited
No reviews yet
Extension Builder in Welwyn Garden City
Expert builders with over 2 years of experience serving north London. We specialize in high-quality Top Service, , extensions and renovations, carpentry, kitchen fiter. Plumbing , electric.delivering professional results on time and on budget. Reliable, clean, and fully insured—get in touch for a free, no-obligation quote today!"
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New Build and Refurbishment Contractor Ltd
No reviews yet
Extension Builder in Welwyn Garden City
At New Build & R C Ltd, we bring skill, dedication, and precision to every project, whether it’s a new build, refurbishment, or structural work. With a strong foundation in reinforced concrete and construction expertise, we deliver high-quality results across a range of services: 🏗 New Builds & Extensions 🏡 Refurbishments & Modern Renovations 🏢 Loft Conversions & Basements 🔨 Underpinning & Foundations 🌿 Landscaping & External Works 🏊 Swimming Pools & Driveways 🏘 Roofing Services We take pride in our craftsmanship and attention to detail, ensuring every project meets the highest standards. Whatever your vision, we make it happen. Get in touch to discuss your next build!
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Arworks
No reviews yet
Extension Builder in Welwyn Garden City
I have had the privilege of working on a 260-year-old Grade Listed building in Islington, London, under the close supervision of conservation inspectors. This project required a careful balance of tradition and innovation — I combined the use of modern machinery externally with traditional, delicate methods internally to ensure the building remained completely scratch-free. My experience has given me a deep respect for heritage projects as well as the skills to deliver high-quality results on modern refurbishments.
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R KELLS LTD
No reviews yet
Extension Builder in Welwyn Garden City
Hello, and welcome! I’m Rkan the owner and lead builder of R KELLS LTD . With years of experience and a commitment to exceptional quality, I’m proud to be known as one of the best builders in London. Whether you’re looking to renovate, extend, or start a completely new project, I bring both expertise and passion to every job. I work closely with my clients to ensure that their vision becomes a reality, on time, on budget, and with the highest standards of craftsmanship. My focus is always on providing a hassle-free experience and delivering outstanding results. Let’s create something amazing together!
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Angle Construction
Rating: 4.7 out of 5
Extension Builder in Welwyn Garden City
We have been in the construction business for over 15 years doing all sorts of works, from minor works to full home constructions. No job to small no job to big. We work in and around London
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Latest review:
Windows & Doors (uPVC & Metal)- 28 Jan 2026
Very unhappy with how things went with Angle Construction overall. Poor comms during the transaction was the first red flag - no communication for 2 days the moment money was sent, however afterwards received an apologetic call - parts ordered and arrived in due course. Andrei turned up, and got to work on removing the old gate, but then started shaving down the post without saying anything -we were told after that the posts were not level. Eventually he said the door would need to be cut, which we agreed to. The door and posts were both cut to fit, but massive gap left at the bottom, and only half of the door fittings and no handles were installed! In addition, where the door was cut and the wood shaved made, a lot of mess was left all over the garden furniture and patio floor. Shocked at the lack of care and professionalism. He was clearly agitated and in a rush to leave. We have a working back door, but it looks like a real botched job. Not happy, and I would not recommend.

4.6

Top rated Extension Builders

Our Extension Builders in Welwyn Garden City, are rated 4.6 out of 5 based on 18 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.