Some of our top rated extension builders in Welwyn Garden City
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With over 35 years of experience in the building industry, we offer a complete A–Z service across all trades — from builders, carpenters, fitters, and bricklayers to electricians, plumbers, and more. Whether it’s a minor repair or a major development project, we provide trusted professionals for every job. At Mazmo, we pride ourselves on delivering exceptional service, reliability, and peace of mind. Our “one-stop shop” approach means you don’t need to look elsewhere — we handle everything under one roof. Quality workmanship. Proven expertise. All in one place.
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Hi there,we are building company we Been in the building business for 15 years we are specialised in extension loft conversation and House refurbishment. pls give us a call happy to help
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TIL Construction LTD is a well-establish company that provides a complete and cost-effective solution for your building needs. We pride ourselves on a team of highly skilled craftsmen and professionals ready to deliver any sized construction project from start to finish. Whether it’s a new build, extension, loft conversion, or renovation, we can help with a portfolio of building work across London and other cities within the UK.
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Hello my name is Costel I have experience in brickwork more then 10 years I have very good reference from customers and proves with photos if you wish to see I Olson have my own company and a van whith tools I have more skills with paving stones etc. And gardening walls and driveway I’m responsible for my work to be everything done..thank you
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Hello I'm a bricklayer with 12 years experience in site work and domestic work. Specialising in extensions, garden walls, re pointing and repairs of any size. No job is to big or to small
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JR Builders London Ltd . Professional Construction Company – North London We are a trusted construction company based in North London, serving clients across London and the northern outskirts. Specializing in house extensions, renovations, basement excavations, and loft conversions, we are committed to delivering exceptional results on every project. Our team maintains the highest standards of craftsmanship, ensuring quality, safety, and attention to detail throughout each project. Whether you are looking to expand your living space or transform your home, we provide reliable, professional services tailored to your needs.
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I’m a skilled bricklayer with years of hands-on experience in building high-quality extensions and new builds. I take pride in delivering reliable, precise, and long-lasting workmanship on every project. Whether it’s a small home addition or a full property build, I ensure every job is completed to the highest standard, on time and within budget. Customer satisfaction and attention to detail are at the heart of everything I do.
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We are a trusted roofing company specializing in loft coversond installation, repairs, replacements, and maintenance. Our goal is to deliver quality workmanship, reliable service, and lasting results for every customer.
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Introducing Earthmates: Your trusted partner for all property needs. We offer comprehensive services in new builds, extensions, landscaping, fencing, loft conversions, and complete property management. Whether you’re planning to build from the ground up, expand your existing space, or enhance your outdoor area, Earthmates delivers expert craftsmanship and tailored solutions to transform your property vision into reality. Let us help you create, renovate, and manage with quality and care at every step.
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Hi, my name is Deep, and I’m the founder of Deep Builders. With over 10 years of experience in the construction industry, I specialize in all types of building work, including: • Home Extensions • Loft Conversions • Full Renovations • General Building and Maintenance At Deep Builders, we pride ourselves on delivering high-quality workmanship, clear communication, and reliable service from start to finish—no shortcuts, no surprises. I’m a professional builder with extensive experience in all types of building work, including home extensions, loft conversions, full renovations, and general construction. I’m dedicated to delivering high-quality craftsmanship, reliable service, and results that truly transform homes. We proudly serve clients across London, Manchester, Luton, and surrounding areas, helping homeowners bring their vision to life—whether it’s expanding space, updating interiors, or transforming a property from the ground up.


