Extension Builders in Mountain Ash

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 5 (2 reviews)

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Some of our top rated extension builders in Mountain Ash

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10358580
Rating: 4.7 out of 5
Extension Builder in Mountain Ash
R&H Building contractors is South Wales based and undertakes general building and landscaping work.
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Latest review:
Bricklaying- 25 Jul 2026
Kieran was great. On time , great job completed and really well priced. We will be using him again on our next property.
RUSSELL & SON'S BUILDERS LTD
No reviews yet
Extension Builder in Mountain Ash
We are a family run business, with over 50 years experience in the construction trade. What we cover, includes but is not limited to: extensions, new build properties, general build and repair, and landscaping including patio. All services range from industrial, commercial and private.
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N&B Construction Ltd
No reviews yet
Extension Builder in Mountain Ash
Hi, we are N&B Construction Ltd, we are a growing team of multi disciplined construction workers with over 50 years experience in the industry.
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NP Construction and Landscaping
Rating: 5 out of 5
Extension Builder in Mountain Ash
Based in Cardiff, NP Construction and Landscaping provide building and landscaping services to customers across South Wales. Established in 2007 the company has many years experience in the construction and landscaping industry.
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Latest review:
Neal was prompt, friendly and very helpful arranging to see a repossessed house I was interested in doing up- the house was sold before I had a chance to put an offer in but I will certainly use him again if I need any quotes, advice and potentially work on future projects.
LA brickwork
No reviews yet
Extension Builder in Mountain Ash
Hello there, I’m Luke from LA brickwork,I have worked all around wales and England building anything from garden walls to extensions to schools to retirement home to schools All brickwork and masonry undertaken. Anything from garden walls to new builds. feel free to get in contact for any job you may need doing. Look forward to hearing from you
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Lmj Build
Rating: 5 out of 5
Extension Builder in Mountain Ash
We are specialist bricklaying and construction company based in Cardiff operating accoss South Wales. We have over 16 years of experience in the construction industry and provide skilled, high quality workmanship to complete your desired project. These are the list of services we provide at LMJ Brickwork and build. • New builds • Extensions • Garden and boundary walls • Retaining walls • Brick slips installation (interior and exterior) • Foundations • Steel work and knock throughs • Repairs • Restorations • Repointing
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Latest review:
Bricklaying- 9 Dec 2025
Good
Primrose Developments
No reviews yet
Extension Builder in Mountain Ash
My name is Jonathan Jones and I'm an Award Winning Builder (best extension to an existing home). There's no job too big or too small and we've helped lots of home owners bring their property transformations to life. I am experienced builder with over 20 years experience in the trade. I can use any materials from stone masonry, timber framed, brick and block. We are a hard working team, reliable and will make sure any job is done to the best of our ability. Quality is key. Some of the works we carry out are: Extensions, New Builds, Renovations, Attic Conversions & Garden Work You can find some of our work on social media. Instagram & Facebook PRIMROSE DEVELOPMENTS
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Sheryn Building Services
Rating: 5 out of 5
Extension Builder in Mountain Ash
We are a small team with years of experience in property maintenance, bricklaying and repointing. If you are looking for dedicated & reliable professionals, please get in touch for a free quote.
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Latest review:
Bricklaying- 7 Jul 2024
Great job - brickwork has been replaced and is nice and neat. Can't fault professionalism and the care that was taken while in my property. Highly recommended.
L & C Dragon Stone Construction
No reviews yet
Extension Builder in Mountain Ash
L & C Dragon Stone Construction – Built With Craft, Care and Family Tradition L & C Dragon Stone Construction is a proudly family-run building company, built on strong values, skilled workmanship and years of hands-on experience. We believe in doing the job right — with attention to detail, reliability, and a commitment to quality that shows in every project we undertake. We specialise in: • Brickwork • Stonework • Blockwork • Landscaping • Groundworks • General Building Services From foundations to finishing touches, we deliver work that is built to last — combining traditional craftsmanship with dedication and pride. Every job, big or small, is carried out with the same level of care and professionalism, ensuring durable results and satisfied clients. Family-run, hard-working and trusted — we build with skill, we build with pride, and we build to last.
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IG plastering&building services
No reviews yet
Extension Builder in Mountain Ash
I carry out a number of trades .carpentry .tilling .plastering .dry lining All work carried out to a high standard.
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Rhys jones
No reviews yet
Extension Builder in Mountain Ash
Ground worker which covers all aspects of Groundworks from digging footings , to finishing works , all aspects of drainage undertaken
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Acl Brickwork
Rating: 5 out of 5
Extension Builder in Mountain Ash
Brickwork specialist
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Latest review:
Extensions- 12 Jun 2026
highly recommend Acl brickwork for any major building work. They recently completed a double extension and a full driveway replacement for us. From the initial quote to the final handover, Ashley and his team were fantastic to deal with. The brickwork on the extension matches our original house perfectly, and the finish inside is flawless. The new driveway looks incredibly sharp and has massive curb appeal. Major construction can be stressful, but they kept the site tidy, stuck to the agreed timeline, and were polite and respectful of our neighbours. A huge thank you to the whole team for a job well done!
Cardiff Extensions ltd
Rating: 5 out of 5
Extension Builder in Mountain Ash
"Welcome to Cardiff Extensions, your premier building contractor specializing in enhancing your living space through expert extensions, attic conversions, kitchen renovations, and bathroom remodels. At Cardiff Extensions, we understand that your home is your sanctuary, and we're dedicated to helping you transform it into the perfect reflection of your lifestyle and personality. With years of experience in the industry, our team of skilled professionals is committed to delivering exceptional craftsmanship and personalized service from concept to completion. Whether you're looking to add extra square footage with a stunning extension, unlock the hidden potential of your attic with a stylish conversion, or elevate the heart of your home with a modern kitchen or luxurious bathroom, we have the expertise and vision to bring your dreams to life. What sets us apart is our unwavering commitment to quality, attention to detail, and transparent communication every step of the way. From initial consultation and design planning to construction and finishing touches, we work closely with you to ensure that your vision is realized within your budget and timeline. At Cardiff Extensions, your satisfaction is our top priority. Let us turn your house into the home of your dreams. Contact us today to schedule a consultation and take the first step towards transforming your living space."
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Latest review:
Darren and his team carried out a single story extension for me and renovated the rest of the property, I had ideas of what I wanted and the boys really made it come to life throughout the property I can’t thank them enough, the quality of workmanship is brilliant in every last aspect of the work they done for me. Darrens team were on site first thing every morning and the house was always left clean and tidy at the end of the day. I would definitely recommend anybody looking to have home improvements done to contact them
AFM (SW) Ltd
Rating: 3.7 out of 5
Extension Builder in Mountain Ash
At AFM we offer a multidisciplinary approach for our customers which includes having electricians, plumbers, carpenters, and building services all under one roof. This offers a number of benefits to our customers: These are lower costs, more control over your project and less hassle with employing different sub-contractors. Our highest priority is; we always carry out projects with professionalism, an experienced workforce and to a high standard of workmanship. AFM (SW) Ltd
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Latest review:
Handyman- 14 Jul 2018
Would not recommend. Grouping poor & cracking, tiles not flush causing build up of grime. Cases not fixed properly. Chipped window sill. Flooring starting to move. Didn't want to leave feedback but 2 years on and we are having to have things replaced. Don't want to ask them back as getting them to replace our bath they broke was drama enough. A lot of money spent on this project we'd of never expected to have to touch it for years. Very disappointing
Williams Carpentry & Building Contractors Ltd
No reviews yet
Extension Builder in Mountain Ash
We are a carpentry & building company, we take on any type of construction work, kitchens, bedrooms, bathrooms, extensions, garage conversions, landscaping & gardening. We have completed extensive work in many schools, office refurbishments, universities, apartment renovations.
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Shaun Jones
No reviews yet
Extension Builder in Mountain Ash
I’m a dryliner but over the years of work I have undertaken multiple jobs. So I’m basically a handy man. And can adapt to most work environments. Also worked for Anglian fitting facials gutters and soffits to a high standard
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Top rated Extension Builders

Our Extension Builders in Mountain Ash, are rated 5 out of 5 based on 2 reviews from customers like you.

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Easily find verified local tradespeople. Just post your job to get quotes from tradespeople near you across the UK.

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

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 Mountain Ash 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 Mountain Ash who are available and interested can respond to your post.

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

What are the hourly rates of extension builders in Mountain Ash?

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

Find extension builders in Mountain Ash with MyBuilder

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

Step 2: Compare different extension builders in Mountain Ash

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

Step 3: Hire Mountain Ash extension builders with confidence

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

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

What to ask a Mountain Ash extension builder before hiring?

Before hiring an extension builder in Mountain Ash or extension building company in Mountain Ash, 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 Mountain Ash?

An extension builder in Mountain Ash 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 Mountain Ash 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 Mountain Ash?

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 Mountain Ash 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 Mountain Ash 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 Mountain Ash

Can an extension builder in Mountain Ash help with planning permission?

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

Many Mountain Ash 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 Mountain Ash help with materials and finishes?

Yes, most extension builders in Mountain Ash 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.