Extension builders in Mountain Ash

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 5 (3 reviews)

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

Select a service

How it works

Post your job for free

Tell us about your job, and we’ll alert suitable tradespeople in your area. It’s simple and free.

Tradespeople respond

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

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 Mountain Ash

359 Results

Sort by:

Celtic Creations Construction Co
No reviews yet
Extension Builder in Mountain Ash
Building South Wales with Expertise and Integrity (Est. 2023, with over 40 years of experience) Your Local Experts in: • Brickwork & Stonework Crafting beautiful, durable structures and walls that stand the test of time. • Patios & Driveways Transform your outdoor spaces with our expert design and installation services. Whether you’re looking for a sleek modern patio or a charming stone driveway, we’ve got you covered! • General Building & Maintenance From minor repairs to major renovations, trust our experienced team to maintain the quality and appearance of your home. Why Choose Celtic Creations Construction Co.? • Local & Trusted Serving South Wales, we are a local company with deep roots in the community. • 40+ Years of Experience Our team brings decades of experience in construction and maintenance to every project. • Friendly & Honest Service We take pride in offering clear communication, transparency, and integrity in all of our work. • Competitive Pricing Affordable solutions without compromising on quality. We’ll work with you to create beautiful results within your budget.
Get in touch
Mike Guest Electrical Plumbing Building
Rating: 4 out of 5
Extension Builder in Mountain Ash
Electrical work 18th edition registered Contractor All plumbing work Extensions building repairs and renovations New builds My own architect Roofing and painting
Get in touch
Latest review:
Bathroom Fitting- 18 Feb 2026
Excellent work from Mike and his team. They kept me informed throughout with regular progress updates and pictures, which I really appreciated. They pay close attention to detail and do the job right rather than cutting corners. As a landlord, I was able to stay completely hands-off and let them get on with it. No chasing for updates or wondering if they'd show up – they were reliable and professional throughout. They started early each day, put in a full day's work, and left everything neat and clean. Would recommend and use them again in future.
David Winter
No reviews yet
Extension Builder in Mountain Ash
Hello my name is David Winter. I went to Barry technical college and studied bricklaying after leaving school (1987). I have worked for many different companies, on large and small sites. In 2002 I started working on my own contracts, doing extensions and refurbishment work. I also work with local trades like window fitters, creating openings for windows and doors. Why choose me? I am honest, hardworking and willing to help clients get the building they want and in budget.
Get in touch
I &S Project House builders
No reviews yet
Extension Builder in Mountain Ash
General Builder with over 25 years experience that include everything from kitchen and bathroom fitting to extensions. Wide range of skills: Plastering & External render Tilling Carpentry Loft room conversion and much more
Get in touch
L.R.T Carpentry & building
Rating: 5 out of 5
Extension Builder in Mountain Ash
All aspects of Carpentry and building work covered and undertaken by Highley qualified tradesmen . We take on all work from site work, self builds a door to extentions .no job to big or small .
Get in touch
Latest review:
Hard Flooring- 16 Apr 2017
Luca is a very pleasant and agreeable person who works hard and demonstrates a willingness to work with the client. Hardworking, thorough and reasonably priced. Highly recommended. ...Luca laid new wood floors in two rooms which involved lifting existing parquet and carpets, work was of a high standard.
Aarons plant hire ltd
Rating: 5 out of 5
Extension Builder in Mountain Ash
Aaron's Plant Hire Ltd is a professional and reliable company specializing in comprehensive groundworks, plant hire, fencing, driveway installations, and landscaping services. With a skilled and dedicated team, we deliver high-quality results tailored to each client’s needs. From excavations and drainage solutions to creating stunning driveways and garden transformations, we ensure every project is completed to the highest standard. Whether you need durable fencing, expert groundwork, or landscaping to enhance your property, Aaron's Plant Hire Ltd is committed to excellence and customer satisfaction.
Get in touch
Latest review:
Landscaping- 6 Apr 2025
Can not recommend Aaron and his team highly enough. Not only did Aaron do a brilliant job but he and his team were all very friendly and conscientious. What are you waiting for! Book them!
Toptobottom renovation
New on MyBuilder
Extension Builder in Mountain Ash
Top to Bottom Renovation provides roofing, property renovation and landscaping services across Cardiff and the surrounding areas. From repairs to full home improvements, we focus on quality workmanship, clear communication and attention to detail, helping you care for your property from top to bottom
Get in touch
Gethin davies
Rating: 5 out of 5
Extension Builder in Mountain Ash
All aspects of masonry ,over 20 years experience. New builds , renovations, extensions , retaining walls, foundations.
Get in touch
Latest review:
Stonemasonry- 29 Jul 2025
Gethin was great. Great communicator, good price, and Dundee took the job within a short space of time. I was very impressed, he did a great job of the wall. I have asked him to look at our garage to convert. Highly recommend 😊
CJS construction & building ltd
Rating: 3.7 out of 5
Extension Builder in Mountain Ash
All aspects of building works undertaken, rebuild walls, install patios, disability ramps, driveways etc. Big enough to deliver but small enough to care!
Get in touch
Latest review:
Electrical- 24 Dec 2021
Promised to look at job but decided hours before he was due that something had cropped up which meant he never turned up!
Littlefields Supplies Ltd
Rating: 4.8 out of 5
Extension Builder in Mountain Ash
Welcome to Littlefields UK. We take great pride in our commitment to exceptional customer service and first class quality assurance. With a keen focus on providing value for money, we strive to fulfil all your construction needs in a flexible and responsive manner. Our dedicated and highly skilled workforce enables us to meticulously plan, execute, and deliver a wide range of projects. As your reliable and resourceful partner, we specialise in building construction, repairs, demolition, groundworks, foundation work, high-spec finishing, site management, and eco-friendly construction for the Net Zero Green Agenda. By embracing the latest technology and prioritising innovation, we ensure the highest standards of construction management. Contact us today for a complimentary consultation and discover why we’ve been successfully building for over two decades. Don’t just take our word for it – hear from our satisfied clients. Let us help you bring your construction vision to life.
Get in touch
Latest review:
Extensions- 2 Jun 2021
Sadly a negative review for Jason vizzard and littlefields uk simply because I’m left with a unfinished project after 6 weeks and now I have to pay someone else to sort his end mess out after Jason went against what we wanted and were quoted for , I’m not going into the ins and outs as Jason will come out with his usual builders excuses,Jason knew exactly the situation and was more than happy to do the work as he was paid nearly 1k more than other quotes to do work. Jason knows my thoughts personally so I will leave at that , Jason and his team are a good bunch off lads and the work they had carried out 90% off the project was off a good standard.
Ashley Ferrell Bricklaying and Building
No reviews yet
Extension Builder in Mountain Ash
I'm a bricklayer by trade and i am experienced in construction & refurbishment.
Get in touch
HILLS CONSTRUCTION
No reviews yet
Extension Builder in Mountain Ash
Hello and thank you for taking the time check out our company! We are family run group with a couple of trusted workers, all of whom have years of experience and a collective knowledge spanning all trades. We have completed a WIDE variety of projects for all levels of clients, we truly do enjoy making your vision a reality, no matter how big or small! We have built lives around building yours and we wish to further this into the online world. Please enjoy our gallery for a sample of the works in which we have completed and we hope to hear from you as we expand further. Trusted and recommended! Public Liability ✅️ Punctual & Accurate ✅️ Clear Planning & Vision ✅️ Clean Perfectionists ✅️ Understanding & Able ✅️ True regards, Joseph
Get in touch
Carl Howard
No reviews yet
Extension Builder in Mountain Ash
I'm a bricklayer with over 25years experience in all aspects of bricklaying. I undertake work from new builds renovation to patios and garden walls. All my work is of the highest standard and the workplace is left clean and tidy after the completion of the job. As you can see i am new to this site but would be able to provide you with many happy customers feedback.
Get in touch
Williams property maintenance
New on MyBuilder
Extension Builder in Mountain Ash
50 plus yrs experience nothing we can't do big or small if I won't have it in my house we won't do it in yours. Customers come first don't do quotes over fone we like to see the job and every one knows what's what. There's a no obligation quote.
Get in touch
M shave construction
No reviews yet
Extension Builder in Mountain Ash
Hi I’m marc and I have 25 years of Experience of being self employed as construction company. I have Experience in general building from extensions to new builds, civils, Hard and soft landscapes including paving driveways and patios. I have also worked as pm on large civil jobs all over the world. We strive to give the customer best quality and performance we can for the best affordable prices. All work is fully guaranteed.
Get in touch
RJD Home Improvements
Rating: 4.9 out of 5
Extension Builder in Mountain Ash
General building, roofing, landscaping, extensions, internal and external plastering including EWI system, PVC windows doors facia boards, guttering. CERTASS registered installer Membership number 24-1369
Get in touch
Latest review:
Extensions- 29 Sep 2025
Our job started out as a small kitchen extension and shower/utility room but grew to also include fitting of a new kitchen, new kitchen ceiling, new double glazed windows to back of house, new garden wall approximately 50ft long and 5ft high and insulation to two internal bedroom walls. Rob and his team are extremely versatile and very approachable. I would certainly recommend them and we are hoping to have some more double glazing work done in the near future.

Top rated Extension Builders

Our Extension Builders in Mountain Ash, are rated 5 out of 5 based on 3 reviews from customers like you.

Quality screening

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.