At DUO, we are committed to being a leader in design & build residential and commercial renovations as well as new construction. We work collaboratively to create custom designs to suit individual tastes, lifestyles and budgets. We provide a dedicated team of skilled professionals who work respectfully with our clients and ensure all aspects of the projects are completed at the highest standards of quality. We believe it is a privilege to be invited into our clients’ homes and offices. We pay attention to every detail to provide peace of mind from start to finish.


Established in 1979 by Pat Malloy and Zoltan Balogh, we continue to improve the customer service experience that has made DUO a leader in the industry. Zoltan retired in 2013. In 2016, Pat named Mark Malouin, John Relouw and Keelan Malloy Partners. Today, the four work together to lead the DUO Team and invest in the future of DUO Building.

We are proud of our work and of the long-term relationships we have developed with our clients. With 39 years renovating homes and offices in London and the surrounding area, we look forward to developing new projects and meeting new clients.

We have expanded our services to include both new custom home and commercial new development construction.