Extension Builders in Welwyn

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.9 (15 reviews)

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Some of our top rated extension builders in Welwyn

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H & A Rail ltd
Rating: 5 out of 5
Extension Builder in Welwyn
We are a Civil Engineering Contractor
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Latest review:
Groundwork & Foundations- 22 Dec 2021
I couldn't have asked for more from this firm.... called when they said they would, arrived early and did everything they could to take away the stress of this stavr in my build. Clean and tidy works, pleasant and polite workforce. I will always use this firm for my work and highly recommend them
c o b building services
Rating: 5 out of 5
Extension Builder in Welwyn
Over 25 year’s experiences and high standard finished quality on all works. High recommendation from my satisfied customers. Customers will have up to 10 years warranty. We have been being collaborating with Ripples Beaconsfield Bathroom , Ripples Wokingham Bathroom and Radlett Premier Bathrooms - three premium designer bathroom showrooms for over 15 years. On MyBuilder profil I update just few pictures with my work but I can provide much more pictures and information about my work. Together with my team we do - Extension - Loft extension - Converted house in flats - Plumbing / central heating system - Full bathroom refurbishment - Full kitchen refurbishment - Polish plaster / Venetian stucco - Plastering / skimming - Painting - Electric - External house insulation - Build wood house - Build summer house ( garden house ) All works is covered by 1000000 liability insurance.
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Latest review:
Bathroom Fitting- 26 Jul 2024
Catalin completely transformed both bathrooms! He listened to our requests and has come with good solutions to our problems, including recessed shelves and replacing the hot water cylinder with a combi boiler, to give us more space in the bathroom. The work was done to a very high standard and has helped us to source materials and sanitary ware. Catalin and his team has done a fabulous job! I highly recommend him!
ERIC GROUP LTD
Rating: 5 out of 5
Extension Builder in Welwyn
Eric Group Ltd has been trading for over 10 years and has completed numerous refurbishment and fit-out projects. We offer free survey and estimates and free specialist advice. If you want a new kitchen, a new bathroom, a house extension or a full house refurb, get in touch for a chat.
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Latest review:
The Job was to extend the rear of the house on the ground floor, open up the kitchen and reception room into one open plan living area, to refresh the rest of the house which included new plaster skim, doors and frames and to fit new bathrooms and kitchen as well as an rewire on the whole house and the construction of a retaining wall in the garden to accommodate the extension. Florins team were excellent from start to finish, the whole project was completed in record time to a very high standard. The 10 weeks turnaround was incredible, we were very happy that Florin was always here at the property or on the end of the phone throughout the process, his professional advice and smart ideas made for a smooth transition from room to room. The team were very hard working, polite and knowledgeable, these guys worked very hard and very quickly which was amazing to see and I was very grateful we were able to move into the property earlier than planned which even saved us money on the temporary accommodation we had! Can’t thank you enough Florin, any small issues we had were dealt with quickly and smoothly, I love the house, the level of work and would 100% use Florin and his team on my next project!
CSO Construction & Surveying Ltd
Rating: 5 out of 5
Extension Builder in Welwyn
At CSO Projects &Surveying Ltd, we specialise in high-quality construction, refurbishment, and property services tailored to both residential and commercial clients. Our experienced team delivers everything from Energy Performance Certificates (EPCs) and stock condition surveys to full refurbishments, extensions, damp surveys/treatment, and garden transformations. We pride ourselves on fast turnaround, honest advice, and a commitment to excellent workmanship. Whether you’re a homeowner, landlord, or developer, we’re here to bring your vision to life with reliable service and transparent pricing.
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Latest review:
Damp Proofing- 11 May 2026
My experience with Samuel was excellent. He provided a professional, comprehensive, and high-value damp survey for my basement. The final report was very thorough, including a detailed technical assessment and numerous photographs that clearly explained the situation. What really stood out was his willingness to answer several follow-up questions regarding the specific remedial work he suggested. His expertise helped clarify that the issues were environmental rather than structural, which provided great peace of mind. Highly recommended for anyone needing a clear, honest, and professional assessment.
Adi
Rating: 5 out of 5
Extension Builder in Welwyn
Hi, I'm a bricklayer living in Luton I'm part of a team of bricklayers, we can work for you if you wish it . We did already a lot's of extenshions and houses in differents sites .
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LQ Construction
Rating: 5 out of 5
Extension Builder in Welwyn
Based in North London and with over 18 years of experience in the construction industry, LQ Construction specialises in bricklaying, renovations, and paving services, offering our clients high-quality, reliable solutions to their construction needs. Committed to delivering excellence in every project we undertake., the extensive experience have equipped us with the expertise to handle a wide range of projects with precision and efficiency. We take pride in our craft and approach each project with a commitment to integrity, reliability, and meticulous attention to detail. Whether you're embarking on a major renovation or need professional bricklaying or paving services, we ensure your project is carried out to the highest standards, on time and within budget. Explore our website to learn more about our services and how you can trust LQ Construction to help bring your projects to life.
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Latest review:
Bricklaying- 11 Jul 2025
Landi was excellent. Finished the job to a good standard
SC DUNCAN CONSTRUCTION LTD
No reviews yet
Extension Builder in Welwyn
SC Duncan Construction provides a general builder service across herts
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Buildrow property services ltd
Rating: 5 out of 5
Extension Builder in Welwyn
We are company that cover all construction work and trades
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Latest review:
Job was a single story extension and fit kitchen,work was completed to a very high standard and was professional at all times,arrived on time every day and work was completed on time. Was very happy with the finished product.
AH Builder
Rating: 5 out of 5
Extension Builder in Welwyn
AH North Builder Ltd specialise in all types of building we are professional and very determined to ensure our clients expectations are met. we have worked on many different building projects for more than 10 years experience.
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Latest review:
Extensions- 13 Nov 2020
Well, I do not usually write reviews, but this time is an exception. So after getting a number of quotations, I decided to go ahead with Fredi. The process was very smooth throughout, Fredi is a great individual and a reliable professional. The plan was to build a rear extension, but working with Fredi, we decided to commission him for the patio, changing all house flooring, kitchen, and two bathrooms. All have been delivered to completion with top-notch results. Most importantly, we have now a new family friend...Fredi the builder!!.. my kids say :)
Skylon Construction Limited
No reviews yet
Extension Builder in Welwyn
Skylon Construction Ltd. successfully delivers projects in mixture of construction, renovation and refurbishment services to individual clients, as well as to other companies. We pride ourselves on an ability to deliver on-schedule without ever compromising our outstanding level of quality. We aim for completing on schedule and believe in zero snaggings and zero incidents policy.
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Smartbuild
No reviews yet
Extension Builder in Welwyn
A.M.C BUILD is an all purpose building company. We undertake refurbishments, new builds, repairs and all. With a quality workforce capable of undertaking all aspects of construction work, from footings to finish.
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Handyman plumber
No reviews yet
Extension Builder in Welwyn
Over 25 years Experience builder on general building, extension, lofts all around house.
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Breheny building and landscaping
Rating: 5 out of 5
Extension Builder in Welwyn
We are professional builders with 4o years experience and 3 generations in the profession, pride our selves on providing good communication and quality of work , and we try to use environmental efficiency on all our projects . 40+ years experience in the building and landscaping trade , friendly and reasonably priced . We have folling certificates Level 2 brick work Street works licence All machinery licenses digger dumper etc Water civils and electric civils license Can supply grab lorry and have waste carrying license .
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Latest review:
Breheny builders visited my property gave me a quote and did a very good good job of the patio exactly in the time frame needed also within my budget they were well mannered and reliable I would definitely recommend and I will be using again to do my drive way
Sami
Rating: 5 out of 5
Extension Builder in Welwyn
Hi, I am a fully skilled plastering with 15 years of experience delivering quality work to your home.I also have experience in all other relating trades like external wall insulation,silicon rendering ect.
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Latest review:
Plastering- 9 Aug 2026
Excellent job. Samis quality of work is second to none , he really cares about his work and is confident he can deliver , which he did. Extremely happy with the render and would highly recommend .
M & G Home Improvement
Rating: 5 out of 5
Extension Builder in Welwyn
With over 12 years of experience in the construction industry and an admirable track record, M&G Home Improvement can have confidence in providing remarkable levels of competence and expertise from new-builds to all refurbishment projects. We are very well recognised within the construction industry for our broad-mindedness, honesty and accuracy in our work. We recognise the needs of our clients and our devoted team that can accomplish even the most complicated challenges with confidence.
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Latest review:
Extensions- 4 Jun 2021
We needed a kitchen extension, and after getting 10 quotes from local builders, M & G were extremely competitive on price. The whole process was made simple, mainly due to the knowledge and communication from Miri and his team. Before I chose M & G, I was invited to see other jobs they were working on and after seeing the first extension, my mind was made up. Miri and his team are Punctual, Tidy, Knowledgeable, Professional, Hardworking and I cant recommend them high enough. I will be hiring Miri and the team for our Loft conversion soon.
K&l contractors
No reviews yet
Extension Builder in Welwyn
Dedicated tradesmen ready to help out with providing a professional and quality service.
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3.9

Top rated Extension Builders

Our Extension Builders in Welwyn, are rated 3.9 out of 5 based on 15 reviews from customers like you.

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Easily find verified local tradespeople. Just post your job to get quotes from tradespeople near you across the UK.

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.