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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Elemari LTD
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
We are an experienced team, working in the Construction Industry for almost 3 years. We normally undertake any type of work, carrying out work of any building, civil engineering, or engineering construction work( Demolition, Rebuilding, Building, Alteration, Loft conversions, etc). We are experienced in Flooring, Painting, and Decorating, Bricklaying, Carpentry, Plastering, and lots more. All our work is guaranteed and fully insured for your peace of mind.
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Latest review:
Painting & Decorating- 22 Mar 2021
work done very quickly and professionally . very friendly would recommend .
Acro design and build
No reviews yet
Extension Builder in Welwyn Garden City
Hi we are new to my builder but certainly not new to the building trade, we have a good team of tradesmen working together for over 20 years,we thrive to achieve and deliver the best possible project for our customers at very reasonable rates.we have experience in all aspects of building commercial and residential and many satisfied customers,please take a look at some of our previous projects not only to see the quality of our works but the scale we can build on Many Thanks John Duncan
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Brati Construction Ltd
No reviews yet
Extension Builder in Welwyn Garden City
At Brati Construction we have over 15 years of experience working on a wide range of refurbishment projects. o.2.o3.3.7.0.1.3.3.3. We work across London on contracts of varying sizes. Please contact us to discuss any project you would like us to look at.
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SM10 Studio Architecture
No reviews yet
Extension Builder in Welwyn Garden City
We are a refreshing and talented team based on the outskirts of central London. We are truly passionate about buildings and are happiest when designing them. We pride ourselves in adopting a fresh approach and our skills extend to designing all types of building. We believe in providing tailored solutions for each and every project and ensure we maintain communication with our clients throughout the process. We offer a bespoke service ranging from planning and building regulations
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Dipesh
No reviews yet
Extension Builder in Welwyn Garden City
Hello! My name is Dipesh, and I have over 11 years of experience as an electrician and security system fitter. Throughout my career, I have developed a strong expertise in ensuring the safety and efficiency of electrical systems and security installations. In addition to my work in electrical and security systems, I also offer top-notch handyman services and possess excellent skills in building outbuildings. Whether you need assistance with repairs, installations, or custom construction projects, I am here to help. I take pride in delivering high-quality workmanship and exceptional customer service, ensuring that every project is completed to your satisfaction. I look forward to working with you and providing the solutions you need for your home or business!
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13-13 BUILDERS LTD
Rating: 4.5 out of 5
Extension Builder in Welwyn Garden City
I do plastering, plaster board, carpentry, partition, roofing, groundwork’s, driveways, gardening, extension, loft conversions
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Latest review:
Carpentry- 25 Apr 2026
Very helpful, fixed my front door sill and other odd jobs around the house. Would call again and good quality
4 brothers brickwork
No reviews yet
Extension Builder in Welwyn Garden City
We are a professional bricklaying company determined to offering our clients the utmost quality at competitive rates. Our projects include both new construction and repairs/restorations. From a wall to a new build project. No job is too small.
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Empe building services ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
BASED IN WEST LONDON EMPE BUILDING SERVICES ltd. ARE A COMPANY OFFERING A RANGE OF BUILDING SERVICES. WE TAKE GREAT PRIDE IN OUR WORK AND PLACE A STRONG FOCUS ON WORKING VERY CLOSELY WITCH OUR CUSTOMERS THROUGHOUT ALL THE STAGES OF THE PROJECT, AS TO ENSURE EVERY DECISION IS DISCUSSED AND QUERYS ARE ADRESSED. OUR REPUTATION IS THE FUNDATION OF OUR SUCCESS. WE TAKE PRIDE IN OUR APPROCHABLE, PROFESIONAL, EFFICIENT AND TRANSPARENT SERVICE. PLEASE VIEW OUR GALLERY FOR EXAMPLES OF OUR WORK.
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Latest review:
Extensions- 31 Jan 2020
We had a porch built by Emil & Peter's team & lead water pipe changed, our house has gone from the tattiest on the street to the smartest now :) The guys turned up on time when they said & worked hard all day, their workmanship is excellent & my neighbour has also used them to do quite a few jobs now& are really pleased with their work. I will definitely be using them again & would highly recommend them!
Codenra ltd
No reviews yet
Extension Builder in Welwyn Garden City
I carry out general building work such as loft conversion, home extenstion , partition , plastering , laminate and tail.
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Sergio
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Hi there !We are an experienced and reliable multi trader team covering the following aspects:glazing,SFS & extensions,flat roofs,any type of cladding,carpentry-all aspects, drylining,exterior /interior insulation installation & rendering,drainage systems & gutters ,plumbing & electrician ( registered and insure -domestic and industrial )and and general DIY jobs. We can help also with interior design and bespoke furniture fabrication of any type (domestic,commercial,offices,interlocking
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Latest review:
Insulation- 14 Feb 2023
I placed an add in mybuilder.com to have my house fully insulated and received many replies including one from Sergiu. After meeting him I felt he was the best placed person to carry out the work as he was the most knowledgeable and seemed to know all about the various types of insulation and which one I needed for my home. He fully explained the procedure from start to finish was always on time and tidied up at the end of each day.His work is second to none and the price was very very competitive in fact much less then the big companies were asking.I am extremely happy with the job and the standard of finish. Sergiu is very police professional and trustworthy and I would have no hesitation in recommending him to anyone on here to carry out work in your home.
Qualitas Build Ltd
Rating: 5 out of 5
Extension Builder in Welwyn Garden City
Quality service assured to all customers. Insured. All work guaranted quality work to domestic and commercial customers. Call us today for a free quotation. Work history Over 19 years of experience working all over London and sorrounding areas delivering excellent finish. We take on general building work, extensions, loft conversion, roofing, renovation, new build, tiling, Plastering.
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Latest review:
Handyman- 23 Nov 2024
Excellent, recommend this guy. He will do the jobs and do it well!!
Total B Construction Ltd
No reviews yet
Extension Builder in Welwyn Garden City
Total B Construction Ltd are leading main contractors providing end-to-end design, construction, and commercial/residential project delivery across London and the South East. Under the executive direction of NVQ Level 7 Project Management, our group operates with corporate precision, rigorous HSE compliance, and dedicated site supervision on every contract. Our Specialized Divisions: • Main Contracting & Refurbishments: Full-scale residential developments, commercial-to-residential conversions, and structural remodeling. • High-End Interior Fit-Outs: Bespoke joinery, architectural tiling, luxury wet rooms, and premium finishes executed by master trades. • Sustainable & Eco Construction: Modern Methods of Construction (MMC), Structurally Insulated Panels (SIPs), and energy-efficient building systems. Why Enterprise & Residential Clients Partner With Us: • Senior Project Oversight: Managed directly by NVQ Level 7 certified leadership to guarantee deadline compliance and budget accuracy. • Full Regulatory Compliance: Fully insured, CDM compliant, with strict quality assurance (QA) frameworks. • Scalable Workforce: Capacity to handle concurrent, multi-phase projects without compromising on execution speed or quality. Contact our commercial team today to schedule an initial consultation or tender review.
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LADO Construction LTD
No reviews yet
Extension Builder in Welwyn Garden City
Hi, I’m Michael from LADO Construction Ltd. With over 7 years’ experience in the building trade, I specialise in delivering high-quality home extensions, refurbishments, and property renovations across London, Kent and Essex. As a Builder and Project Manager, I take pride in running jobs smoothly from start to finish — from foundations and structural work to final finishes. At LADO Construction, our focus is professionalism, attention to detail, and open communication. We work closely with clients, architects, and surveyors to bring plans to life, ensuring every project is completed on time, within budget, and to the highest standard. Whether it’s a new extension, kitchen/bathroom renovation, loft conversion, or general building works, no job is too big or small. We aim to make the building process stress-free and transparent, keeping you informed at every stage. Fully insured and committed to quality, we’re here to create lasting results you’ll be proud of.
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Your Space
No reviews yet
Extension Builder in Welwyn Garden City
We create the perfect space you require. You choose, we build. We can assist, from design, all the way to the finished article. All aspects of buildings works are carried out.
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Nikola Todorov
No reviews yet
Extension Builder in Welwyn Garden City
Skilled handyman. Hardworking professional full with energy and always smiling.
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A. Zen Builders
No reviews yet
Extension Builder in Welwyn Garden City
I have been working as a builder for 25 years. We have a team of 8 who can undertake a wide range of jobs - big and small.
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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.