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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Some of our top rated extension builders in Cornwall

226 Results

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Tindale Building Services
No reviews yet
Extension Builder in Cornwall
We are domestic extension specialists with over 40 years trading experience. A family run business with a different approach to building. All quotations and advice is free. Some of our most recent work is available to view on Facebook.
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D Ashwin
No reviews yet
Extension Builder in Cornwall
High quality and hard working
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JWD Renovate and Build
No reviews yet
Extension Builder in Cornwall
A young and enthusiastic solo tradesman with a keen eye for perfection. JWD renovate and build offers a range of skills to cater many different jobs. With access to a range of other reliable tradespeople covering quality carpenters , electricians and plumbers. Enabling me to be able to perform a variety of jobs of any size from a single wall needing plastered to a sizeable extension.
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C J Boyce Building Contractor
No reviews yet
Extension Builder in Cornwall
I am a general builder that has lots of experience in masonary and carpentry work but can carry out any job to a high level of craftsmanship that is required
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Colvin Builders Ltd
No reviews yet
Extension Builder in Cornwall
40 years experience.new build housing and extensions, renovations, stonework, general maintenance.
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MR Carpentry
No reviews yet
Extension Builder in Cornwall
Trusted local business with 10 years of hands-on experience providing carpentry services to builders and contractors across Cornwall. We specialise in new builds, extensions and renovations. From bespoke builds to home renovations, I’m here to bring quality craftsmanship and attention to detail to every project. 🔨 New builds | Extensions | Renovations 📍 Cornwall
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Estuary Building and Plumbing LTD
No reviews yet
Extension Builder in Cornwall
Estuary Building and Plumbing LTD have been running for the past 10 years and have completed various projects from commercial toilet blocks to single story extensions, we cater for any job big or small. We specialise in renovation works and work on listed buildings. We travel all over Cornwall.
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K & M Building and Landscaping Services
No reviews yet
Extension Builder in Cornwall
Hello! Between me and Mike we have around 25 years experience and have a wide range of skills and abilitys; Carpentry Masonry Groundworks Landscaping Kitchen fitting Bathroom replacements Plastering Project management Loft Conversions And more, see pictures. Feel free to call us or find us on Facebook.
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Molyneaux Builders Ltd
No reviews yet
Extension Builder in Cornwall
Looking for professional and affordable building services in Cornwall? Our builders provide expert New Build Construction, Extensions, Renovations and Groundworks in Cornwall. Molyneaux Builders Ltd are a well-established, reputable, family-run business that covers the whole of Cornwall. Priding ourselves on high quality work and excellent customer service, we rely heavily on recommendations and exceptional word of mouth. As a local contractor company, we are proud to have a proven track record for delivering construction projects and new builds on time, to a high standard and within budget. Striving to provide a service second-to-none, we work closely with each and every one of our clients to understand their needs to design a bespoke solution tailored to their budget and requirements.
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GM Haus Ltd
Rating: 5 out of 5
Extension Builder in Cornwall
Providing the highest standard of work, accredited members of the federation of master builders and trustmark scheme. We are a team of friendly, highly skilled craftsmen covering all aspects of construction from new builds, timber frames, bespoke joinery, renovations and kitchen fitting. We also have access to masons, roofers, plumbers and electrician, completing our team. Our team are fully insured, first aid trained, have full qualifications and a combined 40 years experience in construction.
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Latest review:
Kitchen Fitting- 14 Oct 2018
Sam did a very professional job on our kitchen and down stairs toilet cupboard. He kept us informed of his progress and always made sure that the works progress and completion was to our expectation. The work was started and fineshed on time and within the budget we had planned. All areas were left in a clean and tidy state.
J Prescott Building & Plastering
Rating: 5 out of 5
Extension Builder in Cornwall
I have been working within the industry for over 20 years on a self employed basis. Learning my skills with various established builders within my local area. I am a qualified plasterer which I have been mostly doing for over 10 years. This also includes work with lime products and have managed to build a repeat custom for various work needed.
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Latest review:
Plastering- 28 Jun 2017
James and associate carried out all works to a high standard despite some pretty poor weather!Very pleased and will use again.
Cornish extension company LTD
No reviews yet
Extension Builder in Cornwall
Transform your home with Cornish Extension Company, with a commitment to exceptional craftsmanship and customer satisfaction, we bring your vision to life, whether you're looking to expand your living space or refurbish your existing our experienced team works closely with you every step of the way, ensuring that each project is tailored to your needs and completed on time and within budget. Trust Cornish Extension Company to add value and beauty to your home-where your dream space becomes a reality!
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John Wilson
Rating: 5 out of 5
Extension Builder in Cornwall
I am a Carpenter & Joiner with over 40 years experience in the trade working mainly on my own but using other trades as needed.
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Latest review:
Kitchen Fitting- 13 Jul 2015
Was able to help out immediately as we were in a very difficult situation. Sorted within the day. Thank you. Will be employing again for more carpentry.
Jb carpentry
No reviews yet
Extension Builder in Cornwall
I am a level 3 qualified carpenter. Currently work as a sub contractor but am looking to go out on my own. I mainly do second fix work but have also got experience doing 1st fix.
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Dennison construction
No reviews yet
Extension Builder in Cornwall
Hi I’m Paul and my son’s name is Taylor. I’ve personally been building for over 30 years and have vast experience in most fields. Friendly and trustworthy aswell as hard working. Plenty of references if requured via repeat customers.
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Virtue Contracting
No reviews yet
Extension Builder in Cornwall
We are a property maintenance/construction company. Between myself and my partners we have over 75 years experience between us in various aspects of the building trade. We cover any work from as small as cleaning gutters or hanging doors to full renovations and new builds. Our service to our customers is paramount on a proactive or reactive basis, as well as the safety and well being of all our employees.
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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.

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 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.