Extension Builders in Welwyn

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.8 (14 reviews)

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Some of our top rated extension builders in Welwyn

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Michael Biggs
No reviews yet
Extension Builder in Welwyn
Quick, efficient and neat work. Team of two. Can do everything start to finish
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PWD CONSTRUCTION LTD
Rating: 4.9 out of 5
Extension Builder in Welwyn
I established my business to meet the needs of homeowners looking for skilled and qualified tradesmen that put trust at the top of their requirements. From small jobs to large extensions and landscaping we can help to make your property dreams come true. Money back guarantees offered.
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Latest review:
Extensions- 26 Nov 2020
Paul was absolutely great to work with on our project. I would have no hesitations in hiring him and his team again, which we plan to do. He was great as the plans changed, and when unexpected things cropped up he communicated with us really clearly and promptly. The quality of the work is really high, and even as there have been (really) minor snags to deal with after he's been great about these too.
Arlo
No reviews yet
Extension Builder in Welwyn
Our company offer these services: Landscaping Services •Paving •Driveway •Fencing •Grass •Cleaning •Drainage •Garden Repair •Concrete Base •Wooden Pergola
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Urwin services
No reviews yet
Extension Builder in Welwyn
We are a driveway clearance and demolition specialist, all aspects of clearance and demolition undertaken, competitive rates clean and efficient working in home counties and north London
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T.G & Sons Construction Ltd
Rating: 5 out of 5
Extension Builder in Welwyn
I have worked in Construction since 1990. I have owned and run my own Business since 1998. We undertake projects from £1k to £2M. New Builds, renovations, Extensions, Loft Conversions, Conservatories, Outbuildings, full Refurbishments and Modernisations. We have all trades available and take on every aspect of the building trade. We also provide Architectural and Maintenance services. We Plan, Design, Build & Maintain.
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Latest review:
Restoration & Refurbishment- 6 Aug 2019
We are so pleased with the result. All the guys were friendly, helpful and hard working. They did exactly what they said and kept us fully informed. We should have done this years ago. I fully recommend them. A great bunch.
Enea Group LTD
Rating: 4.9 out of 5
Extension Builder in Welwyn
Enea Group LTD has undertaken all forms of design and construction work, from Refurbishments, House Extensions and Loft Conversions, to remodelling also for the New Home Builds. In our team we offer a wealth of experience and extensive construction knowledge.
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Latest review:
Groundwork & Foundations- 8 Oct 2024
Great service.have asked them to come back for future jobs
Evanescence builders
Rating: 5 out of 5
Extension Builder in Welwyn
Evanescence Builders is a proud, family-run business with over 10+ years experience in the trade. Dedicated to delivering exceptional craftsmanship and a personal touch to every project. We treat every job as if it were our own, striving for perfection from start to finish, providing guarantees on all work completed and fully insured. So give us a call to get your free quote today!
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Latest review:
Groundwork & Foundations- 30 Jun 2026
We asked for someone to give us availability and a quote to deep a 1m deep hole to bury our beautiful 14 year old cat. Bradly responded with such a heart warming message and offered to come and do this for us. He completed the grave with such care, respect and kindness we will always remember. Thank you Bradly your kindness has meant more than you can ever imagine. Our beautiful boy has been laid to rest in such a beautiful place thanks to you.
JLita Construction
Rating: 4.7 out of 5
Extension Builder in Welwyn
J Lita Ltd Building Service is a business established in 2016. We have more than 10 years' experience in providing building services around North London, London, St Albans, Watford, Luton, Amersham, Aylesbury. We specialise in a wide range of services across all aspects of house refurbishment, construction, including house remodels, renovations, extensions, and more, ensuring that we can handle every aspect of your project from start to finish. We provide expert solutions for projects of all sizes. Our team of professionals is highly skilled and dedicated to delivering exceptional results on every project. We have the knowledge and expertise to get the job done right the first time. At J Lita Ltd, we believe that communication is key to the success of any project. That's why we work closely with our clients to understand their needs and provide customized solutions to meet their unique requirements. We are committed to delivering projects on time, within budget, and most importantly to your satisfaction. We look forward to helping you with your projects. Estimates/quotes are available on request, please don't hesitate to give us a call anytime.
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Latest review:
Extensions- 2 Aug 2023
JLita construction were hired after a competitive quote was agreed to carry out work on my kitchen extension project last year. Prompt and dependable Jetmir’s team worked productive long hours with a clear understanding of my wants and requirements. Where it was possible to accommodate they did. Any remedial work was quickly picked up and completed in good time to the required specifications. After completion of work each day, the space was swept and tidied and the space made as usable as possible. I am extremely happy with the work carried out and the attention to detail applied by Jetmir and his team and would, (and have already) happily recommend JLita Construction for any building works. More than satisfied. Many thanks Jetmir and team. Scott
Skaci & Sons Ltd
Rating: 5 out of 5
Extension Builder in Welwyn
General work from scratch to finish. New Build, extensions, loft conversion, painting, plastering, basement, bathrooms & kitchens. 18 years experience in the trade.
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Latest review:
Extensions- 16 Sep 2021
Very happy with the extension. Eddie and his team were best priced which was the reason we went with them, and he brought in a crack team of brickies, roofers and notable mention to the tilers.
Cc brickwork
No reviews yet
Extension Builder in Welwyn
Brickwork Repointing Extensions Any aspect of building
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Pgm grup services ltd
Rating: 5 out of 5
Extension Builder in Welwyn
Welcome to PGM GRUP SERVICES LTD . We are a professional and reliable groundworks and landscaping team dedicated to transforming and maintaining your outdoor spaces to the highest standards. With extensive experience in all aspects of ground engineering and hard landscaping, we pride ourselves on delivering top-quality craftsmanship, durable structural work, and competitive pricing. No matter the scale of the project, we treat every property with maximum respect, ensuring clean, efficient, and precise execution from start to finish. Our Specialist Services Include: Driveways & Paving: Block paving, resin, concrete, and pathways built to last. Fencing & Edging: Secure, high-quality fencing installations and neat perimeter edging. Brickwork & Walling: Professional bricklaying for garden walls, retaining walls, and boundaries. Drainage & Eco Channels: Complete drainage solutions, surface water management, and eco channel installations to prevent flooding. All Groundworks: Excavation, site clearance, foundations, and sub-base preparation. Why Choose Us? Guaranteed Workmanship: Fully committed to structural safety and flawless finishes. Honest & Fair Pricing: Transparent, free, no-obligation quotes with no hidden costs. Reliable & Tidy: We arrive on time, work efficiently, and always leave the site spotless. We are fully insured and ready to bring your project to life. Contact us today to discuss your requirements!
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Latest review:
Groundwork & Foundations- 28 Jun 2026
Petru did an excellent job for us at a very reasonable price. A very humble person who strives make his customers happy. I loved his work and would highly recommend him.
Joe Hilley
Rating: 5 out of 5
Extension Builder in Welwyn
St Albans Brickwork specialise in all elements of residential and commercial brickwork construction projects. Our skills cover a wide-range of projects, home extensions and renovations, driveways & patios, garden walls, repointing, garage conversions and large building contracts. With more than 15 years’ experience in constructing new homes and delivering home improvements throughout St Albans, we are well equipped with the expertise to complete any size job to the highest possible standard.
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Latest review:
Repointing- 29 Jun 2017
Joe did an excellent job with our garden steps, despite the fact that we initially messed him about with timing of the job. He got the work done by our deadline, to a high quality, and for a good price. Highly recommended.
CPK Building & Maintenance
No reviews yet
Extension Builder in Welwyn
Hi, I'm chris from CPK building & maintenance we are a small building company, we take on all kinds of building and maintenance jobs offering a great affordable service. Over 15 years experience.
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Jengis Fahri
Rating: 5 out of 5
Extension Builder in Welwyn
Hello, my name is Jengis Fahri. I am a specialist bathroom fitter with a plumbing background and over 14 years of experience in construction and property development. I work alongside a trusted team of five full-time skilled tradespeople, with no subcontractors involved. All works are backed by a one-year workmanship guarantee, and I offer a flexible, milestone-based payment structure aligned with project progress. Kind regards, Jengis Fahri FORMA Design & Build Ltd
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Latest review:
Restoration & Refurbishment- 23 Feb 2026
Friendly, professional and accommodating, Jengis has been a fantastic contractor to work with and we will definitely be using his services again. He worked within tight timeframes for us, and went above and beyond when we had a problem in the work area meaning he had to stop for the day. One of the better people I've worked with in my life!
B & M Home Improvement
Rating: 5 out of 5
Extension Builder in Welwyn
We are a local and reliable Plumbing, gas safe and Home Improvement Company in London and surrounding areas.I gained my experience working in the Plumbing and gas department. No matter whether you require help with plumbing, power flushing, boiler installation, bathroom, kitchen, extention, flooring we take on all building work. We provide a full interior decorating service for domestic and commercial.
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Latest review:
Extensions- 10 Apr 2014
Max and Bob completed the extension on time and within budget. There were no hidden extras and despite Bob being on holiday for two weeks, Max worked hard and lon. The extension is 6m x 5m. There were issues with Building Control which Max sorted out and did everything to meet their requirements. The extension is built to a high standard, kitchen cabinets fitted well, tiling very good and we are pleased with the quality of their work. We are using B&M again as we are confident that although they are not tghe cheapest, the quality of their work is of a high standard. Besides, it is always a pleasure to deal with Max who is a gentleman, patient and listens to what is required.
JCL Renovations Ltd
Rating: 5 out of 5
Extension Builder in Welwyn
We are a construction with over 20years experience between the team, We undertake all aspects of renovation work including house renovations and extensions. We also have extensive experience in laminate, hardwood flooring and decking installation. We offer a solution for any projects from start to finish all in one place.
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Latest review:
Repointing- 23 Jan 2020
Job well done. Will definately use in the future.

3.8

Top rated Extension Builders

Our Extension Builders in Welwyn, are rated 3.8 out of 5 based on 14 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.