Green roof reshapes a massive retail project

By Jesse Sanchez. 

A sprawling green roof and recreational space required a mix of structural systems designed around demanding loads, seismic conditions and community needs. 

A massive retail development in Mexico City’s Santa Fe neighborhood is designed to blend into the landscape surrounding Parque La Mexicana while supporting vegetation, recreation and complex structural requirements. The project includes a 144,522-square-foot Costco warehouse within a 524,549-square-foot development composed of three structures: a metal building for the warehouse, a post-tensioned concrete parking garage and a loading dock constructed with conventional concrete and metal decking. Much of the development is concealed beneath landscaped and recreational spaces, including a green roof planted primarily with native succulents spanning 10 species. 

Discussing the warehouse’s material choices in an Arcat Detailed podcast interview, MG2 Architects’ Maribel Barba, AIA, explained, “The metal structure is made from 80% recycled steel. This minimizes the amount of new material utilized. In addition, the decreased thermal mass of the metal reduces building heat absorption, as compared to a typical masonry block wall.” 

The green roof also introduced structural considerations, although its loads remained within a range that allowed MG2 to use the same amount of steel it typically uses for most Costco projects. The superimposed roof load was 30 pounds per square foot overall and 49 pounds per square foot around a 2-foot roof perimeter. 

Other areas required different structural solutions. The three-level parking garage supports public sports courts while meeting restrictions on the structure’s height. Describing the post-tensioned concrete system, Maribel noted, “This is a very efficient design that utilizes less concrete than other common concrete structures while still holding heavy loads from the sports park. The thickness of the floors is a little over 5 inches, which is quite thin compared to other concrete structures.” 

The team also addressed poor soil conditions and Mexico City’s seismic environment with seismic gaps and joints between the project’s three building types. Planted berms help further conceal the development, while drainage systems collect stormwater runoff for Parque La Mexicana’s fountains and lakes. 

Reflecting on the completed project, Maribel shared, “Every hurdle we overcame and every milestone we reached added to a growing sense of achievement that culminated when we witnessed the impact of our work firsthand, the creation of a space that enriches lives and fosters a strong community spirit.” 

Learn more about how the Mexico City project combines a green roof, specialized structural systems and community recreation spaces to meet demanding site conditions!