Extension Builders in Welwyn

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.7 (13 reviews)

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Some of our top rated extension builders in Welwyn

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GARDEN AND BUILDING SERVICES LIMITED
New on MyBuilder
Extension Builder in Welwyn
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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Davies Construction & Brickwork ltd
No reviews yet
Extension Builder in Welwyn
Build developments group ltd is a construction company serving Buckinghamshire and Hertfordshire over the years, the director has been established in the building industry for 13years. We offer the complete package from demolition, excavation, brickwork to just getting you into a watertight shell. We cover all digger/driver work, Demolitions, Excavations, new builds, extensions, garden walls, flint work and landscaping.
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R KELLS LTD
No reviews yet
Extension Builder in Welwyn
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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U.K.R
Rating: 5 out of 5
Extension Builder in Welwyn
We are new to mybuilder but have been in the building Trade for 30 years as a Bricklayer, working for myself for the past 20 years Mainly dealing in Extensions and Brickwork. I have a team of tradesmen - a Carpenter Plumber, 2 good Labourers / ground workers.
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Latest review:
Can't speak highly enough of this company.work was not only complete on time but was finished to a high quality. Very polite and helpfull workers.hopeing to get this company back summer 2018 to do our rear extension. Great choice of builders from this site. Thanks my builder .
Peter Build
Rating: 5 out of 5
Extension Builder in Welwyn
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.
K&L Fixing Ltd
No reviews yet
Extension Builder in Welwyn
Hello I’can offer any type of refurbishment Loft conversion,side extension Kitchen,bathroom,laminate,painting
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New Build and Refurbishment Contractor Ltd
No reviews yet
Extension Builder in Welwyn
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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GRB Building and Home Improvements
Rating: 5 out of 5
Extension Builder in Welwyn
At GRB Home Improvements we have over 15 Years experience in general building contracting including extensions, kitchen and bathroom refits, loft conversions, garden landscaping, patios and outbuildings, drainage and groundwork, drives and general building maintenance. We passionately believe in customer satisfaction and strive to ensure that our quality work is delivered on time, as per the agreed schedule, and that we come in on budget.
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Latest review:
Carpentry- 24 Jan 2021
George came to do up our hallway. He laid flooring and installed new spindles and a handrail on our stairs too. He did a wonderful job on the whole lot and we were very happy with him. We were awkward and changed our mind on the first laminate flooring that I had picked out online, he ripped it up and started again with the new flooring we picked and it was no hassle to him. George is a lovely fella, trustworthy and professional. Would highly recommend
SOLI CONSTRUCTIONS
No reviews yet
Extension Builder in Welwyn
As a Construction & Consultancy Firm with over 24 years of work experience in building industry, We offer a wide range of services to our clients including: -All Types of Extensions -Loft Conversions -Flat Conversions -New Builds -Tanking and Damp-proofing -Wall and Chimney Removals -Steel Beam/Frame Installations -Structural Repair and Retrofitting -Renovation and Refurbishment -Planning Application Drawings and Submissions -Structural Calculations -Building Specifications Documents
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Arworks
No reviews yet
Extension Builder in Welwyn
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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Angle Construction
Rating: 4.7 out of 5
Extension Builder in Welwyn
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.
Gww construction
No reviews yet
Extension Builder in Welwyn
I am a highly skilled carpenter joiner , with the vision to give the very best of work from myself . Whether it be from fitting wood floors to hanging doors . -fit hand made bespoke wardrobes. -Pitch roofs from plans ,or to certain design -hand craft gazebos to any design and style, and have the resources to supply the timber needed . - I have designed and built every project from star to finish, according to each customers style and taste .
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P Neaves Brickwork
No reviews yet
Extension Builder in Welwyn
My names Paul Neaves I’ve been bricklaying and In the building game nearly 50 years and have loads of experience
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Preet builds
No reviews yet
Extension Builder in Welwyn
Hello We do all type of brickwork,Paving and all type of building works
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Dan’s Team Projects Ltd
No reviews yet
Extension Builder in Welwyn
25 y of experience in building sector. Working as a multi trade person for companies now set up own . Always good communication and problem solving.
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Pascu Building Services
No reviews yet
Extension Builder in Welwyn
Been in the building industry for over 15 years working on a self employed basis, for the past 3 years I am running my own company having different trades subcontracting for me, we mainly deal with general building projects as (house extensions, loft conversions, general refurbishments and house alterations we have a long relation with Waltham Forest Council and Barnet Council as we had a fair amount of jobs in these areas
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3.7

Top rated Extension Builders

Our Extension Builders in Welwyn, are rated 3.7 out of 5 based on 13 reviews from customers like you.

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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.