Extension Builders in Welwyn Garden City

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 Garden City

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AMG LONDON LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
AMG places great emphasis on the importance of up to date methods of design and construction. As a key player at the forefront within the market place we specialize in building Extensions, Loft conversions, Drylining, ceilings, painting and decorating to complete internal building fit out.
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Latest review:
Stefan did an extension for my flat from the installation of structural steel, to the roof, and demolition. To building the shell and all cosmetic work inside. I am very happy with the work. Time keeping was good, pricing was good he was open and honest throughout, he was very tolerant and easy to work with. Always positive and willing to help if there were any issues. He would help resolve any issues in the quickest and best way possible. Very happy. I would happily recommend him.
A lama construction ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Drylining and plastering , making good , building wall , mf ceiling , plasterboards , rendering, painting.
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Latest review:
Carpentry- 9 Oct 2022
Excellent work; came exactly on time and went above and beyond. Job a little more involved than I’d realised but no complaints from Alfred he purely got on with the task at hand and I was incredibly happy with the work and would highly recommend.
p&d building services
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are a professional Building Company,specialising in house extensions, loft conversions,refurbishments,new builds,etc.With over 18 years of working experience in UK,we have gained a good name through hard work,professionally done and a good working relationship with our customers.
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Latest review:
Roofing (Pitched)- 11 Jun 2015
Paul has done a good job quickly with reasonable price.
Irz construction ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Irz construction ltd was created 5 years ago always were recommend to costumers all around London Type of jobs we do Refurbishments Extension Loft conversation Gardening Driveways Painting decorating All projects we did are available to visit and see It in person also ask the owners about their experience with us The director has been 7 years on this industry previously managing another successful construction company
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Latest review:
Restoration & Refurbishment- 19 Nov 2019
Iljaz and his Team were brilliant! I was slightly concerned having no reviews. They found the leak, fixed it and patched up the wall in very tidy and professional manner. He did say he wouldn't be able to come today and updated me, however he made time to come in-between his day to sort out my issue. Not many true trades people like this and very honest and stuck to his word. I would definitely recommend him and would not hesitate to use his team again. Thank Iljaz!
K build
Rating: 4.4 out of 5
Extension Builder in Welwyn Garden City
About Us With over 25 years of experience in the UK construction industry, our team provides a full range of high-quality building services for homes and properties across Luton and surrounding areas. We specialise in all aspects of domestic plasterwork, painting, plasterboarding, stud walls, carpentry, bathrooms, kitchens, extensions, roofing, and driveways — handling every stage of the project with care and precision. We pride ourselves on our attention to detail, cleanliness, and reliability. Our goal is to deliver outstanding workmanship at fair and reasonable prices, ensuring every customer is completely satisfied with the results. No job is too big or too small — all types of building work are undertaken with the same dedication and professionalism.
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Latest review:
Plastering- 15 Aug 2022
Skimming job completed quickly but now that decorations have started the painters are picking up ripples in some of the walls that rushed.
H P JONES BRICKWORK LIMITED
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
With over 15 years experience, H P Jones Brickwork Ltd prides itself on providing a trustworthy and efficient service to the highest standard. We understand having work carried out can be stressful. But whilst providing you with top workmanship throughout your project, our team aim to keep disruption to a minimum. Customer care is paramount in our service and we believe that regular communication with our customers is key to ensuring they are happy with the service provided.
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Latest review:
Harry was a wonderful contractor to use. Polite, friendly, kept us informed on how the work would take and how it was progressing. Extremely professional, I wouldn't hesitate in using him again and recommending him to family and friends.
AAB Home Builds Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are limited co. General builders. WE TAKE CARE TO NEW BUILD, EXTENSION AND LOFT CONVERSION Specialists in exterior RENDER (WEBER ,KEY RENDERING&SILICONE RENDERING)and interior plastering. Bathrooms kitchens and refurbishment works.
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Latest review:
Plastering- 23 Dec 2016
Denis did a good job plastering and retiling a small area of my kitchen. He responded to my ad promtly, came round the next day to quote and carried out the work 2 days later as requested. He was professional, polite and left my kitchen clean and tidy after the work was done. I'm happy to recommend him and would contact him again if needs be.
WOODLEY RAY LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Woodley Ray was formed early this year by David Ray and Sam Woodley, both expirenced in all forms of construction for over 15 years. Mainly concentrating on domestic extentions, alterations and loft conversions. With already several happy customers happy to provide references. A limited company, VAT registered.
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Latest review:
Committed to delivering great work, and being a successful construction business owner. Strives to grow and get better at what they do there work is excellent. Had work completed both internal and external over a few years would highly recommend Woodley Ray Ltd they are very reliable & extremely professional.
imsbuilders
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
I have over 40 years of experience in the industry. I am a fully qualified bricklayer and also a fully qualified carpenter. I have had the pleasure of constructing many extensions new builds and home renovations for my clients, ensuring the whole project runs smoothly and safely
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Latest review:
Carpentry- 28 Apr 2024
Great experience. Bill was very nice, knowledgable and quickly fixed an issue with our unsupported floorboards, for excellent value too. Would definitely recommend!
Smartbuild
No reviews yet
Extension Builder in Welwyn Garden City
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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360Build Solutions Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
360Build Solutions Ltd - specialised in Extensions (single or double storey), Conversions - Loft, Garage, Full Refurbishments including Kitchens, Bathrooms, Home Cinema and complete New Builds - Home Office, Gym. We deliver top quality of work and we always look at many options to come to the most logical and profitable solutions for our clients and to build long and lasting relationships. Free site visits and Estimates - learn more about us in About...
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Latest review:
Extensions- 17 Nov 2019
Marius is the best builder ever! I can not recommend Marius enough, if he can do your job I would bite his arm off! He and his team are hard working, efficient and tidy. Nothing was too much trouble, the job barely ran over schedule and I now have the most fabulous new home! This is the way building work should be done!!
Plasterer
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
With over 9 years experience and a real focus on customer satisfaction, our team of experienced professionals will produce a smooth finish every time on your walls and ceilings. We also do all aspects of rendering and EWI SISTEM (external wall insulation ). Always on time and on budget.
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Latest review:
Insulation- 5 Sep 2024
Fantastic work by Andrei, Ciprian and their team. Highly skilled and hard working team, starting on time (8am) every day and working until late, clear communication as the job was progressing, clear and fair pricing, attentive to details, and happy to accommodate non-standard request like 100mm EWI. Highly recommended!
Joe Claydon & Sons
No reviews yet
Extension Builder in Welwyn Garden City
Hi, we cover all aspects of building and landscaping. With 20 years experience we adapt to new and existing customer needs as some plans change, we want to deliver your projects with our passion and skill to make each job unique
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Alpha Construction
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
A local British family run construction company with over 30 years experience in the building trade. We take a structured planned approach to all projects big or small and deliver high quality work at a fair price. Free no obligation quotation service please feel free to book an appointment today.
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Latest review:
Alpha construction did a 2 storey side and roof extension, loft conversion, complete renovation, drive and patio for us. In short they took a dated 3 bedroom house and converted it into a modern 5 bedroom house. We invited over 10 builders to bid and Alpha supplied the most detailed quote and were the only one to meet each deadline. They were also always quick to answer questions. That level of customer service and professionalism was reflected in all latter dealings with them. They started on time, they finished on time. They updated us on a regular basis and found innovative solutions to unexpected issues e.g. inaccurate architectural drawings. They kept to budget and were transparent with costs. My husband particularly appreciated that they recommended value options or found lower cost solutions to our ideas. We also got access to a wealth of subcontractors. Ross put together a high quality team from the expected plumbers, electricians etc. To the unexpected such as window vendors / kitchen suppliers. All of which gave great value and high quality services compared to alternatives we found ourselves. Everyone at the house was polite and conscientious, in fact neighbours have been asking for quotes since. Since moving in we've had a lot of people comment on the great finish of the work they did. The house looks lovely and I would be happy to show others thinking of using them. I have recommended them to my friends and that's about the best compliment I can give.
Hertfordshire Brickwork Limited
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Hertfordshire Brickwork Limited., where quality comes first and competitively priced, too. 21 years experience constantly in that field of work. I pride myself on the outstanding quality and the great customer service I provide - that's a promise. It's one of many things I've been extremely proud of throughout my career. I also hold the highly recognised SMSTS Site Management Safety Training Scheme certificate so you can be sure everything will be well planned out safely and correctly. Kind regards, Danny Marsh
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Latest review:
Bricklaying- 14 Mar 2016
He completed the job - really impressed - Very Polite - he worked really hard and made a fantastic path for us. Highly recommend this guy.
m j m builders
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We do most types of building work also resin drives all types of landscaping. I have worked in construction since leaving school, I have been working foreman for firms also contracts manager for a firm specialising in care homes and I am now 53 years old.
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Latest review:
Extensions- 18 Jan 2020
In October 2018, I asked Michael to do a rear part single storey part double storey extension. Michael completed the job mid January 2019, which also included relaying the patio, fitting a pre-bought kitchen and building a new porch. Michael, Bill (the electrician) and the rest of the team have done an excellent job transforming our home into something so much more than it was. I was very impressed with his work ethic and his knowledge, and appreciated the advice he gave us which showed his experience. The electrician also was able to successfully rewire our home to bring up to the required standards and was willing to work on weekends to get the job done (that was partly our fault, sorry!). Any issues and disputes, of which there were very few mind you, were dealt with promptly and properly. All in all, if you're looking for a trustworthy, high quality builder in the Hitchin/Letchworth area then do get in touch with Michael. Thanks again for the excellent work! Also, if you'd like to see his completed work, please drop me a message and you're welcome to come and have a look at the work that was done.

3.8

Top rated Extension Builders

Our Extension Builders in Welwyn Garden City, 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 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.