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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Adrian
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Ady Construction Services LTD is a full-service building company providing high-quality construction, renovation, and property maintenance solutions across residential and commercial sectors. From groundwork, brickwork, roofing, and extensions to full refurbishments, kitchen and bathroom installations, landscaping, and decorating, we cover every aspect of building work. With a skilled team, attention to detail, and a commitment to excellence, we deliver reliable and cost-effective services tailored to each client’s needs — from start to finish.
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Latest review:
Landscaping- 23 Mar 2025
Great job - promptly done and good quality!
Build Four Four Limited
No reviews yet
Extension Builder in Welwyn Garden City
Build Four Four is a full service building construction company dedicated to building and improving residential and commercial structures according to client needs and desires. We specialise in transforming your home into what you always wanted. Be it a loft conversion, extension or a new build from scratch. You can be rest assured that at BFF, quality, precision and excellence comes first. Based in Hertfordshire but also covering London and Essex, the team at BFF is ready to give your space whatever updates it requires. Just give us a call or enquire online today and we’ll get back to you as soon as we can with a quote.
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LDK BRICKWORK
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Brickwork ,extentions, restoration, pointing , retaining walls
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Latest review:
Bricklaying- 13 Aug 2021
We agreed on a price which was satisfactory, Keaton and his team were very professional job completed , brick laying to a good standard. Very happy would recommend friends.
SPEKT GROUP LTD
Rating: 4.8 out of 5
Extension Builder in Welwyn Garden City
We are a team father and sons, with over 30 years of experience in Wood Occupations and construction sites, who's goal it's to provide our customers with quality services.
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Latest review:
Carpentry- 11 Mar 2025
Great work and would recommend!
AVR Construction
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
I have a 10 years in construction industry ( landscaping) dancing paving foundations and many more For a fare quote contact me .
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Latest review:
Groundwork & Foundations- 7 Sep 2026
Came a short notice, worked hard, did a good job and left everything tidy - thank you.
MNM CONSTRUCT LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
The company was set up following years of working on small and large projects for both private and public clients subsequently understanding the continuous increase in demand of manageable, cost effective and quality projects.
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Latest review:
Plastering- 26 Jun 2016
We hired Manu and his team to plaster our summerhouse, relocate two radiators and fit a new bulkhead ceiling in the lounge and install LED tape. He was knowledgable, professional and considerate and I highly recommend Manu and his team. Not only did he understand the project for the bulkhead, but he came up with another suggestion which we went with, and friends and family agree looks amazing. The finish on the plasterwork is perfect and Manu and his team worked hard and even left the summerhouse cleaner than when they started! It is great to work with a team who pay such attention to detail, listen to the client and get the job done to a high standard. It was a risk to go with Manu as he didn't have any feedback when I hired him. I actually got him to quote so I could compare prices with someone else I had in mind to do the job, but when I met Manu I felt he would be the better person to do the job as he listened and understood exactly what I wanted and so I ended up hiring him instead. I wouldn't hesitate to hire him for any future jobs. Thank you Manu and team!
Beam Developers ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Unlocking a world of possibilities, BEAM Developer Ltd specializes in an array of dynamic property services. From sleek architectural designs for planning applications to robust structural packages, we've got your project covered. Our expertise extends to seamless renovations, repairs, and captivating new extension and conversion builds. Elevate your vision with BEAM Developer Ltd – where excellence meets innovation!
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Latest review:
Ahmad and the Beam Developers team did an amazing job on my rear extension. We were very particular with our requests and are generally picky people but they were very patient and accommodating to our every request. We were shown the drawings, made adjustments and managed to tailor the project exactly to what we wanted. The finished results were amazing. No big project for us soon but should we plan to do the loft will definitely use Ahmad and his team again.
NWLB Limited
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
In building trade since 2003. Fast, good prices, reliable. RENOVATIONS. BATHROOMS. ELECTRICAL. PLUMBING. TILING. FLOORING. DECORATION. KITCHENS. My fees: £135 PER DAY or £95 PER A HALF A DAY.
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Latest review:
Hard Flooring- 27 Jul 2026
Excellent work from Eugene and will be using again
JNH Builders
No reviews yet
Extension Builder in Welwyn Garden City
JNH Builders are a local building company based in Hertfordshire specialising in home extentions and brickwork, however all aspects of building work are undertaken. At JNH Builders we take pride in ourselves by keeping all work to a high standard at competitive rates, and insure you'll be kept up to speed with all job progress.
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Everything! Build and maintain
New on MyBuilder
Extension Builder in Welwyn Garden City
With over 30 years experience in the building trade, we bring a wealth of knowledge and hands-on expertise to every project. Our team covers all aspects of building and maintenance, delivering reliable, high-quality work with honesty and care.
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Stag Builders of Hertfordshire Limited
No reviews yet
Extension Builder in Welwyn Garden City
Stag Builders of Hertfordshire limited is a member of the Federation of Master Builders and the National Federation of Builders. We also have Trustmark - Government Endorsed Quality Licence No. We are a family-run business with specialities in garage conversions, house extensions, loft conversions, kitchen installations, bathrooms, patios, garden decking, and external wall rendering.
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Miron
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
General billing Painting, loft conversion, extension, handyman
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Latest review:
Handyman- 15 Sep 2021
He was very well manned and professional and did a little work more work without charging extra. He is very tidy and the price was very reasonable. I will certainly hire him again in the future . Thx Miron xxx
NexLevel Contractors Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are a small, family owned, London based building company with an excellent reputation for workmanship and customer service. Our people hold many trade specific accreditations such as Gas Safe Register and NICEIC and should give you the comfort that you are dealing with professionals. We are accredited by the of Federation Of Master Builders & full members of TrustATrade. With a team of qualified professionals we offer a complete service for all of your domestic & commercial needs.
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Latest review:
Restoration & Refurbishment- 11 Jan 2018
Dorian Lula and his team completed in excellent terms full flat renovation. Dorian is very accommodating and his communication is fantastic as we didn’t have any misunderstandings ... I am glad I have met him and for sure I will be keeping in touch for my next project. Special thank you to this site for this fantastic opportunity as I feel I got a very good deal Yours truly Violeta Ku
SJC Buiders
Rating: 4.4 out of 5
Extension Builder in Welwyn Garden City
GENERAL BUILDER
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Latest review:
Extensions- 13 May 2025
Steve and his team are great. From the initial enquiry through to completion Steve was prompt, professional, friendly and communicated continuously. Completed the job to a high standard and Im really happy with the finished porch. I would definitely use Steve again if I need any further work done. Very reliable. Thank you
Homerunbuilders Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
At Home Run Builders, we are experienced carpenters and builders specialising in all types of renovation, refurbishment and building work. From small improvements and repairs to complete home renovations and extensions, we provide a reliable and professional service tailored to every customer. Our services include carpentry and joinery, kitchens and bathrooms, flooring, plastering, decorating, structural alterations, loft conversions and home extensions. We take pride in delivering high-quality workmanship, attention to detail and excellent customer service. Whether you are looking to modernise a single room, renovate your entire property or create more space with an extension, Home Run Builders can help bring your ideas to life. We work closely with our customers from the initial consultation through to completion, making sure every project is completed to a high standard and with minimum stress. If you are planning a renovation, extension or building project, Home Run Builders are here to help.
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Latest review:
Hard Flooring- 16 Aug 2026
Put this job request up with very short notice and this was not a problem. Delivered a high level of work quality and even quoted for other work. Highly highly recommended. Thanks
MRB Refurbishments and Extensions Ltd
No reviews yet
Extension Builder in Welwyn Garden City
Having over 30 years experience within the building industry I have unrestricted experience in all aspects of work, both private and public. Supported by an incredibly skilled and amazing team I am able to undertake projects of varying size.
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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.