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Extension Builders in Cornwall

Easily find verified Cornwall Extension Builders. Just post your job to get quotes from MyBuilder's Extension Builders in Cornwall.

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Tradespeople respond

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Once your job is posted, you’ll get responses from interested tradespeople through the website.

Review profiles and choose

Review profiles and choose

Browse profiles, work history, and feedback, then choose who you wish to share your details with.

Some of our top rated extension builders in Cornwall

227 Results

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  • General Builders. Extensions. Garage conversions. Loft conversions. Renovations. Wall and floor tiling. Wet room installation/ renovation. Bathroom installation/ renovation. Kitchen fitting installation/ renovation. Plumbing. Please do not hesitate to contact us. All Angles SW LTD - Facebook We look forward to meeting you.

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  • Extension Builder in Cornwall

    Hello

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  • Cornwall Extension New Build may be new to the Mybuilder platform however we are far from new to the trade, we boast a strong team of 5 builders with over 100 years of experience combined and a network of high quality tradesmen at our disposal to cover all aspects of any project. We pride ourselves on sticking to the budget and producing quality work.

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  • Extension Builder in Cornwall

    I’ve got 9 years experience on site work predominantly doing carpentry but have experience in other aspects of site work. I’ve carried out work from the ground up covering all areas of carpentry from simple studwork to finishing details there’s no job to big or to small. I cover the whole of Cornwall based around Newquay and Penzance. Follow my instagram for photos of work carried out - CARPENTRY CREATIONS CORNWALL Fully insured.

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  • Hello! My name is Tom , I’m an experienced and reliable groundworker covering Cornwall and Devon offering a full range of groundwork services for domestic and commercial projects. With a strong focus on quality and precision, I specialise in drainage, trenching, foundations, concrete bases, slab laying, landscaping preparation, and site clearance and much more. I take pride in delivering every job to a high standard, ensuring work is completed safely, on time, and with minimal disruption to your property. I have the equipment and expertise to handle projects of all sizes — from small garden makeovers to large-scale site preparations. Friendly and approachable, I’m committed to clear communication and providing honest, competitive quotes. Whether you need a new patio base, driveway excavation, or complete groundwork for an extension, I’m here to help. Fully insured and dedicated to customer satisfaction — please get in touch to discuss your project or arrange a free estimate

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  • Extension Builder in Cornwall

    Here at KJ Building & Plastering we take the utmost pride in every job that is undertaken. Client satisfaction is top of the list. We specialise in masonry work such as stonework, blockwork, plastering and rendering. Owner/director Kaylup has over 10 years experience in the trade. He completed a 3 year apprenticeship to gain his Nvq level 3 in masonry and was awarded apprentice of the year.

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  • Extension Builder in Cornwall

    At J C Orchard Masonry & Groundworks Ltd, we specialise in delivering high-quality groundworks, masonry, and landscaping services across Cornwall and the South West. With years of hands-on experience and a strong reputation for reliability, we take on everything from small domestic projects to full residential park-home developments, drainage installations, foundations, retaining structures, and full site packages. We’re a tight-knit, skilled team that prides itself on doing things properly — clear communication, tidy work, and solutions that last. Whether it’s preparing bases for new park homes, constructing gabion retaining walls, installing services, building bespoke driveways, or managing larger developments from start to finish, we bring the same level of care and attention to every job. Customers choose us because we’re problem-solvers. We don’t just “turn up and crack on” — we plan, advise, and deliver work that genuinely adds value to your project. If you’re looking for a dependable, straight-forward contractor who sticks to deadlines and gets the details right, we’re exactly that. Fully insured, fully equipped, and always happy to discuss upcoming work or provide advice.

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  • Extension Builder in Cornwall

    I run a small business of 8 staff we complete work to a high standard and to budget , I have a number of happy customers with references.full refurbishment, barn conversion, new builds plus all aspects of stone work under taken

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  • Extension Builder in Cornwall

    Hard working very knowledgeable of the trade been doing the trade for 7 years, went to college to get level 2,

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  • Extension Builder in Cornwall

    Hi, I’m Billy @ BHConstruction, we are a small Cornish based company specialising in masonry but also carry out every aspect (bar plumbing and electrical) on new developments, refurbishments and extensions. We have been working on a word of mouth bases for the last few years and have been fortunate enough to be part of some incredible projects, we are now looking to continue improving our portfolio by helping customers make there dream projects become reality!

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  • Extension Builder in Cornwall

    I've been building for 18 years and very good at what I do and i take alot of pride in my work but anyone can write stuff to make them stand out from others but it's proving yourself on the tools and that's what will make me stand out from the rest

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  • Extension Builder in Cornwall

    Solo Handy Man Builder…Hardworking individual with creativity and knowledge who takes pride in providing a good service…Generally I work on small projects, domestic builds, alterations, renovations, extensions and landscaping. General home DIY from flat pack to kitchen fitting assembling including any other internal work.

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  • Extension Builder in Cornwall

    Self employed plaster/builder 35 years experience Honest tradesman

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  • Extension Builder in Cornwall

    We are Spindrift Services, established in 2026 after many years working individually as sole traders and successfully collaborating together for the past four years. Michael is a classically trained carpenter with 25+ years of experience in the industry. He has extensive knowledge across all aspects of construction and has completed a wide variety of projects, including doors, kitchens, bathrooms, roofing, extensions, conversions, outbuildings and much more. Liam has over 10 years experience, originally specialising in landscaping and external construction projects such as fencing, patios, walling, pergolas, and luxury treehouses. He later progressed into interior renovations, property conversions, and full rebuilds. We also specialise in the installation and remediation of fire doors and have worked extensively with hospitals, schools, and student accommodation across the UK. We pride ourselves on delivering high-quality workmanship with a premium finish while treating every client’s home with the same care and respect as we would our own. Reliability, professionalism, clear communication, and attention to detail are at the heart of everything we do. Please take a look through our gallery to see examples of our completed projects

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  • Extension Builder in Cornwall

    JMR Construction – Building with precision, passion, and purpose. We turn your vision into reality, whether it’s a custom home, renovation, or commercial project. Quality craftsmanship, clear communication, and lasting results—that’s our promise.

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  • Extension Builder in Cornwall

    About Me I’ve been working in the building trade for over 10 years and am based in Withiel, covering Mid and North Cornwall. What I Do I specialise in property renovations and refurbishments, offering everything from small upgrades to full-scale projects. I can also organise and manage a trusted team of skilled tradesmen to ensure your job is completed on time and within budget. Why Choose Me I take pride in my work, with a keen eye for detail and a commitment to high standards. I always go above and beyond to make sure customers are fully satisfied, and much of my work comes from repeat clients and recommendations.

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What types of services are offered by local extension builders in Cornwall?

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 Cornwall 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 Cornwall who are available and interested can respond to your post.

Browse profiles, read customer reviews and get quotes from your chosen Cornwall extension builders, all before you decide who to hire.

What are the hourly rates of extension builders in Cornwall?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Cornwall will charge between £16 and £42 per hour.

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 Cornwall extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Cornwall home extension project is likely to cost.

Find extension builders in Cornwall with MyBuilder

Hiring the right extension builder in Cornwall 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 Cornwall extension builders. Once your job is live, we’ll share it with home extension builders in Cornwall who can express their interest.

Step 2: Compare different extension builders in Cornwall

When you start receiving interest, review profiles of local Cornwall extension builders, check their previous work, and read real customer reviews. Ask about timelines, materials, and request detailed quotes.

Step 3: Hire Cornwall extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Cornwall, 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.

Cornwall extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Cornwall extension builder before hiring?

Before hiring an extension builder in Cornwall or extension building company in Cornwall, 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 Cornwall?

An extension builder in Cornwall 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 Cornwall 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 Cornwall?

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 Cornwall 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 Cornwall 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 Cornwall

Can an extension builder in Cornwall help with planning permission?

Yes, many extension builders in Cornwall 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 Cornwall handle everything from design to construction?

Many Cornwall 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 Cornwall help with materials and finishes?

Yes, most extension builders in Cornwall 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.

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