We share a profound commitment to contextual, responsible, meaningful and beautiful design.

Who We Are

DTAH is committed to design with a conscience. We stand up for what we believe in. We care about undertaking work that is socially inclusive and relevant, and that contributes to the betterment of our cities and communities. 

How We Work

Collaboratively. We believe that the most successful projects are a result of open, honest and continuous dialogue between all parties involved – our client, design team, consultants, other stakeholders, and the community at large. Within the studio, collaboration between senior and junior staff encourages design innovation while providing great mentorship to the young and talented studio team. 

What We Do

We aim to deliver projects that are greater than the sum of their parts, which enhance the lives of their users, as well as honour their specific environments and surrounding communities. Project delivery is our strength, and respecting both schedule and budget is essential to the success of every assignment.


DTAH has been designing landscapes, buildings and communities for over 40 years.

Staff poses outside the Colborne St. Studio – the first home of the firm.
The DTAH Studio at 50 Park Road

The building and unique site speak directly to our design philosophy, which for over four decades has worked to respect, preserve, and enhance the public realm, while celebrating the intersection of built and natural form.

Selected Clients

Over the decades, DTAH has worked on hundreds of projects in both the public and private sector.


We seek excellence in all dimensions of our work, and have established a solid reputation for providing insightful design solutions for complex problems.

161 Awards

Select Awards

Lifetime Achievement Award

  • Canadian Society of Landscape Architects

Award of Merit - Transportation

  • Ontario Consulting Engineering

Award of Excellence

  • Toronto Urban Design Awards

Award of Excellence in Heritage Restoration

  • City of Hamilton

Design Excellence Award

  • Ontario Association of Architects

83 Lectures

Most Recent

RAIC/OAA Festival of Architecture, Ottawa, 2017

  • Heart of the Nation: The Long Term Vision and Plan for Ottawa's Parliamentary and Judicial Precincts

IDS, Toronto, 2017

  • Memory, Change, and Design for the Public Good 

AIAS Quad Conference, Toronto, 2017

  • The Future of Sustainability 

BRIDGE Conference, Ironbridge, 2017

  • New Bridges in a Canadian World Heritage Site – An Architect’s Perspective

Grey to Green Conference, Toronto, 2017

  • Queen's Quay-Catalyst for Revitalization: A Social and Ecological Success Story

497 Publications

Select Articles

Canadian Architect, July 14, 2017

  • Why Canada Needs a Public Architecture Policy

Inside Toronto, March 7, 2017

  • Renovation Options Revealed for Field House at MacGregor Playground

NOW Magazine, July 6, 2016

  • Are we killing Yonge Street?

Toronto Star, May 6, 2016

  • At 100, Jane Jacobs more relevant than ever

NOW Magazine, October 4, 2016

  • Wellington Destructor rises again

While our capabilities are broad, we cultivate a culture that seeks a profound understanding of our craft and supports the pursuit of excellence at every level.

See Our Work