Extension Builders in Gwynedd

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Some of our top rated extension builders in Gwynedd

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L.BELL construction
No reviews yet
Extension Builder in Gwynedd
L.BELL construction has a proven track record for a groundwork contractor , effective problem solving and attention to detail and our goal is to meet and exceed the expectations of every customer. We take on all types of jobs from small domestic work to larger commercial projects, all carried out to the highest standards, and at very competitive prices. New builds Groundwork contractor Drainage Septic tanks /treatment plants Concrete works Flagging Fencing General maintenance
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RAW Saer Coed
No reviews yet
Extension Builder in Gwynedd
With 19 years in the building trade, we bring skill, reliability, and pride to every project. As a fully qualified joiner, we cover all aspects of building work — from joinery and renovations to groundworks and excavations with our own machinery. ✅ Fully insured ✅ Professional service ✅ Quality workmanship guaranteed Whether it’s a new build, an extension, improving your indoor or outdoor space — we’ve got the experience and equipment to get the job done right. Contact us today!
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TG Glazing and Flat Roofing
No reviews yet
Extension Builder in Gwynedd
- Based in Anglesey and covering North Wales. - We specialise in flat roofing, roof lanterns, double-glazing windows and doors, conservatories, porches, fascias, soffits, and guttering. - All work guaranteed. - Fluent in Welsh and English, we provide reliable, professional service for all your home improvements.
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Sion Pritchard
Rating: 5 out of 5
Extension Builder in Gwynedd
With over 20 years experience on everything from small extensions to new builds, and everything in between we can offer a quality service backed up by trusted sub contractors that we have been working with for years.
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Latest review:
Bricklaying- 11 May 2024
From start to finish Sion was very professional and very knowledgeable which was very helpful, in regard of how to repair and improve our garden patio. Sion replaced damaged bricks, created a new entrance to the patio and installed coping to the bricked wall. He also repointed the patio floor and added a new step.The finished result is of high standard and we love how it looks now. Sion worked tirelessly for two and a half days (in the heat ) and tidied up after, which we appreciated. We definitely recommend him and will definitely contact again. Diolch Sion
Cristo Construction LTD
Rating: 4.8 out of 5
Extension Builder in Gwynedd
With over 30 years of experience in the building industry - Cristo construction strive to deliver the very best with a first class service from start to finish, with an eye for detail and high quality finish,we are a company offering superior quality craftsmanship and exceptional value for money. "Our work is our passion!"
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Latest review:
Extensions- 21 Feb 2022
Fantastic work by Tony and team. Helpful and accommodating with all requests. Highly recommended.
David Turnbull
No reviews yet
Extension Builder in Gwynedd
D Turnbull Bespoke Joinery & Construction…is a professional joinery company delivering high-quality bespoke woodwork for residential and commercial projects across the UK. We specialise in all aspects of joinery and construction. Combining traditional craftsmanship with modern techniques, we produce joinery that is durable, precise, and finished to a high standard. We work closely with homeowners, architects, and contractors to ensure each project is carefully planned, well executed, and completed on time. With a strong focus on quality, reliability, and attention to detail
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DA Building and Joinery
No reviews yet
Extension Builder in Gwynedd
We at D A Building and Joinery carry out all aspects of building works and specialise in joinery. Our small team are fully certified and we work closely with local architects and building control on our larger projects. From design stage to project completion. There is no job to small either.
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Dylan Roberts
No reviews yet
Extension Builder in Gwynedd
Time served bricklayer been employed for the last 22years , self employed before my employment with 40 years experience, very experienced in bricklaying , all groundworks , patios, boundary walls from building extensions to bungalows and houses
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D O ROBERTS BUILDERS
Rating: 5 out of 5
Extension Builder in Gwynedd
We are a family run business and have a vast 65 years experience within the building industry.We have been members of the FMB for many years now and have gained awards for the standard of our work.We have predominantly worked on old farm and barn conversions over the last 15 years we undertake all aspects of building and joinery and offer all trades.we pride ourselves on honest hardworking ethics and punctuality and transparency is key.
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Latest review:
Extensions- 30 Jun 2019
Dafydd came out and quoted the job straight away. He has done a fantastic job and went over and above what we expected. He even tidied up some of the hall paintwork and skirtings for us. We had a very old extension which leaked and was poorly built. The extension Dafydd has built is now not only watertight, but looks amazing! And has a lovely light shaft which really brightens it up. Very high standard of work. VERY pleased and would highly recommend him.
Marco Kitchen Bathroom &Decorator
Rating: 5 out of 5
Extension Builder in Gwynedd
Hi I have 18 years experience with Carpentry Joinery and Decorating I do high standard of work
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Latest review:
Kitchen Fitting- 5 Sep 2020
Work was carried out efficiently and within budget
Carlisle construction
No reviews yet
Extension Builder in Gwynedd
Carlisle Construction is a trusted name in the industry, bringing over 30 years of experience to every project we undertake. Known for our commitment to quality, integrity, and craftsmanship, we specialize in delivering reliable construction solutions tailored to meet the unique needs of each client. Whether it’s residential, commercial, or renovation work, our skilled team ensures every job is completed on time, on budget, and to the highest standards. At Carlisle Construction, your vision is built to last.
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aaron williams plastering
Rating: 5 out of 5
Extension Builder in Gwynedd
my name is aaron, i am a NVQ qualified & time served plasterer, I completed my training in llandrillo college (rhos-on-sea). i have been plastering for over 15 years & have excellent knowledge in damp and woodworm, dry rot as i specialized in this for a number of years. many types of plastering such as rendering, (Krend) pebble dashing, moulding work, and all indoor skimming and boarding & prep work. I’m also Experienced in renovating properties to. i’m friendly ,honest ,clean and reliable
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Latest review:
Plastering- 26 Aug 2021
Aaron completed the rendering job promptly and fixed the door so we were very pleased and will contact again in the future. I would recommend
A S Building and property maintenance
Rating: 5 out of 5
Extension Builder in Gwynedd
At A S Building we’re a small honest company who work with our customers to achieve a cost effective high standard finish no matter what your project is.
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Latest review:
Extensions- 20 Mar 2025
A highly professional job on building a summer house. Finished to a very high standard. Excellent communication throughout , no issues and very friendly service. Thanks Alex & Alfie for all your hard work. 💪😀
AJ Building Services Anglesey
No reviews yet
Extension Builder in Gwynedd
We are a family run business with over 50 years of experience in the industry. We offer building services for small repairs / home improvements to high quality renovations / extensions and new build projects. Call or message for a free quote.
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AJ Building Contractors Anglesey Ltd
No reviews yet
Extension Builder in Gwynedd
AJ Building Contractors Anglesey Ltd is a family run buisness with over 50 years experiance in the construction industry. We have expertise in both construction management and carrying out various types of projects from small scale alterations to whole extensions or new build properties.
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Black Dog Joinery
Rating: 5 out of 5
Extension Builder in Gwynedd
Hi at Black Dog Joinery, I offer the best carpentry and joinery service available. I like to plan the work ahead, be upfront and honest with customer and delivering the quality of service people require. I started off as a bench joiner, making bespoke joinery, such as, doors, windows, stairs and kitchens, once these items were manufacture and taken to site I would fit them. I then moved to working on site, and have done your general carpentry and joinery work such as skirting, hanging doors, fitting kitchens and tiling and constructing timber walls and installing insulation. I am currently based on Anglesey and will work any on the island and along the north Wales coastline up to Colwyn Bay, As well as down to Aberystwyth.
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Latest review:
Carpentry- 16 May 2026
Dunster house summer house very happy. Good communication throughout build and attention to detail . Reliable skilled Tradesman.

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

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

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

What are the hourly rates of extension builders in Gwynedd?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Gwynedd 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 Gwynedd extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Gwynedd home extension project is likely to cost.

Find extension builders in Gwynedd with MyBuilder

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

Step 2: Compare different extension builders in Gwynedd

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

Step 3: Hire Gwynedd extension builders with confidence

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

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

What to ask a Gwynedd extension builder before hiring?

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

An extension builder in Gwynedd 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 Gwynedd 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 Gwynedd?

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 Gwynedd 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 Gwynedd 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 Gwynedd

Can an extension builder in Gwynedd help with planning permission?

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

Many Gwynedd 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 Gwynedd help with materials and finishes?

Yes, most extension builders in Gwynedd 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.