Your local team of builders in Cardiff

Specialising in renovations and extensions, the team at Roundhouse Builders Ltd has over 39 years of industry experience and are the ideal choice for your next home project. Get in touch via email for a free quotation or bespoke consultation.

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Specialising in extensions and renovations

Roundhouse Builders Ltd is a family run business who specialise in the addition of small, medium and large extensions to domestic properties within the Cardiff area. Our comprehensive package takes care of everything from the initial concept and design through to the build and finishing touches. Our expert team are also happy to project manage your build for no extra charge when required. All estimates are provided free of charge and all work comes with a written guarantee for your peace of mind.


We've built an enviable reputation over the last 39 years and have become highly respected in the building industry. A large portion of our work comes from customer recommendations and word of mouth and often take on projects for friends and family of previous clients.

Previous projects

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Strong foundations, perfect finishing touches

We want you to be 100% happy with the service we provide, which is why we provide clients with constant updates throughout the build, giving you chance to provide feedback and make amendments where necessary. By having a designated project manager on site, you know who to go to if you have any questions or issues, further strengthening our business and client bond.

"Mike and the team were recommended to us by friends and I can absolutely say that they were spot on. From the very beginning they were helpful and worked with us to make sure we got the very best from the plan.
On time every day, the team were Professional and friendly with a fantastic work ethic. Nothing was too much trouble and they guided us through the process from start to finish.
I would absolutely recommend this first class team for any work and we will certainly use them again in the future."

- Jason F

Make us your first choice of builder in Cardiff!

Send us an email to request your bespoke quotation or to discuss your next project with us.

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