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

228 Results

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B H Builders
Rating: 5 out of 5
Extension Builder in Cornwall
B H Builders & property maintenance is a small building company in the heart of Cornwall, with over 20 years experience in all aspects of masonry and general building work from drainage right through to roofing. specialising in block/brickwork, plastering and rendering.
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Latest review:
Plastering- 23 Aug 2020
Ben was very professional and plastered my wall to a high standard. Very polite and tidy. Would definitely recommend and hire again.
Mariusz Carpentry
No reviews yet
Extension Builder in Cornwall
High quality carpentry services, 30 years of experience.
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GTB Builders
Rating: 5 out of 5
Extension Builder in Cornwall
I’m Gary, I’ve been in the trades for over 40 years covering various projects ranging from small repair work to building multi million pound houses. Im fully covered and insured and provide a reassuring process throughout the project. Using this app to fill space in the diary due to other customers having some delays. I cover all aspects construction. Some of services I provide are : New builds, Loft conversions, Extensions, Groundwork’s, Roofing, Summer house/sheds, 1st/2nd fixCarpentry, Kitchen/bathroom fitting, Internal/external doors and windows, Driveways, Full refurbishments and renovations, Masonry, Rendering/Plastering, Landscaping And more! Feel free to get in touch.. there are no jobs to big or small. Thanks, Gary.
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Latest review:
Roofing (Pitched)- 24 Feb 2026
I was very grateful to Gary and his team for getting me out of a hole when my 80 year old outbuilding roof was blown off by the January storm. From first to last he acted in a very professional manner by clearly outlining the issues that needed to be addressed and the way he would resolve the problem. I have nothing but praise for the whole experience and should misfortune ever come my way again I would, without hesitation, reach for the phone and ring him. When you find someone you can trust you invariably keep their phone number.
J&F Carpentry and Construction
No reviews yet
Extension Builder in Cornwall
With over 25 years experience we cover all aspects of building. We are fully Qualified in Carpentry to the highest level. As Carpentry being our my main trade we also have a vast amount of experience in all aspects of building. We are very conscientious and reliable. Please take a look at our facebook page and Contact us Via the Facebook if you have any enquiries as we do not respond to requests via MyBuilder. Thanks.
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HAMSON BUILDING
No reviews yet
Extension Builder in Cornwall
Hi I'm Craig, Fully qualified and 18 years of experience. I am willing to look at a range of jobs, small or big. Landscaping, barn conversions, extensions, block work, driveways, patios, plastering and many more, just ask!
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AGB Carpentry
Rating: 1 out of 5
Extension Builder in Cornwall
Hello my name is Alex. Carpenter by trade although have experience in most trades as I’ve been in the trades for about 11 years. I was employed for a few years and have recently decided to work for myself. I absolutely pride myself on finishing to the highest standards and am always looking for ways to increase both skills and knowledge. Below are jobs I cover: Extensions Renovations New builds 1st/2nd fix Carpentry Kitchen fitting Fencing Brick/block build Groundwork’s Soffit/Fascia/Guttering Loft conversion etc. I look forward to hearing from you. Please feel free to ask me anything! Thank you
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A p t home and garden maintenance
New on MyBuilder
Extension Builder in Cornwall
Over 40 years in the industry working as a general builder with the last ten as working foreman I strong work ethic, clean and tidy, professional
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NGL Construction
Rating: 3 out of 5
Extension Builder in Cornwall
With over 17 years experience in the construction industry NGL Construction is able to offer you wide range of trades. From new builds to renovations, plastering to bathroom fitting every job we do is done to the highest of standards with 100% commitment. We have built our reputation on quality work, competitive pricing and a friendly service.
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Latest review:
Bricklaying- 30 Jan 2018
never came, phoned text last minute, he found better paid jobs due to gales that passed through at that point in time.
Sam Faulkes
No reviews yet
Extension Builder in Cornwall
TF
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Cornwall Carpentry & Flat Roofing
No reviews yet
Extension Builder in Cornwall
We specialise in New builds Extensions Renovations Flat Roofs Pitched Roofs Cladding Decking All works are insured and come with guarantees
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TJ Worsey Building
Rating: 5 out of 5
Extension Builder in Cornwall
hi,my names Tim. Im an honest , hardworking , experienced builder who has pride in leaving a good job. I have over 30 years experience in multiple trades.
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Latest review:
Extensions- 23 Jul 2023
Tim was very professional. I wanted a porch within the regs allowing no planning permission. He required payment in 3 parts allowing me to check his work and him to buy the supplies he needed. He explained his ideas clearly and this is what he built. I was so pleased with the result that he built a porch at our other house, again doing a fantastic job within the spec we gave him.
DWA Carpentry
No reviews yet
Extension Builder in Cornwall
Over 20 years experience Fully qualified NVQ level 3 Carpenter. Timberframe specialist. Looking to take on Timberframe new builds & Extensions. First & second fix carpentry also welcome & Kitchens.
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Ardent SW Ltd
No reviews yet
Extension Builder in Cornwall
Ardent Construction is a friendly and reliable general builder that specialises in one off development properties. We also have a fully independent small works department that can handle most of the smaller domestic jobs. So overall there is nothing we can not handle with our own team of experienced and trained trades men.
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Webber and son builders Ltd
No reviews yet
Extension Builder in Cornwall
We are a family run building company who specialises in new builds, extensions and house renovations. We have a team of trades in house including electricians, plumbers, carpenters, painters and decorators and roofers
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DT CARPENTRY AND CONSTRUCTION LTD
Rating: 5 out of 5
Extension Builder in Cornwall
Hi. My name is Dean and I am the director of a local carpentry and construction business that covers all aspects of construction. I have been in the trade for over twenty years now and I have built a great team of tradesman to cater for all of your development and construction needs from kitchen and bathrooms to full builds and extensions/ loft conversions.
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Latest review:
Extensions- 29 Jun 2025
Sun, 29 Jun at 20:50 Dean and his team were a pleasure to work with and he was excellent at communicating. Also great at finding solutions for various challenges that developed as the project unfolded. Trustworthy and fair- would certainly recommend.
W.Mckay & Sons
Rating: 5 out of 5
Extension Builder in Cornwall
I have worked in the construction industry for almost 20 years from leaving school and I completed a level 2 NVQ trowel occupations back in 2010. I have worked alongside many experienced builders in that time and developed sound hands on experience leading to the development of my own business. I have gained all the skills and experience needed for a complete build from preparing and pouring concrete foundations, brick/block laying, installing premade roof trusses, felt and battening to laying the slate/tiles, 1st fix stud walls dot and dap plaster boarding, skimming, rendering, and landscaping. I have worked on small projects such as extensions right through to large mass house builds working alongside project managers. I pride myself in working in partnership with my customers to achieve their wishes whilst being open and honest about the project length and costs so there are no surprises or hidden costs on completion. I believe communication is key in achieve the best outcome for my customers and I will work to the best of my ability to meet all the requirements, keeping you informed at every step of the project. W Mckay and Sons cover all areas in Cornwall and into Devon and can offer a wide range of services at a reasonable rate and we can provide references to support previously completed jobs. We are reliable and punctual and will turn up as promised. We will work in a tidy, professional manner keeping the work site as tidy as possible when not working.
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Latest review:
Landscaping- 29 Aug 2024
Will came and looked at the job, we talked, some banter, my wife and I felt comfortable with him and bearing in mind Sam my wife would be in and around whilst I at work that was very important…a good start. We had the quote, happy with the cost and the plans after my very poor landscaping drawing and a date was penned in. 8am Will and able teammate Kev arrived to start the excavating to take out the grass and make good ahead of building brick circles to be surrounded with blue slate clippings and artificial grass in the centre of the circles plus extending the patio. 10 days or so later including working the bank holiday we have a lovely garden to be proud of. Both Will, Kev and digger driver John were polite, courteous and respectful of the property and in our opinion have done a cracking job… Needs arise in the future, only one phone call to be made in my opinion…top job guys

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.