Contextually-Rooted Green Roof

Apr 20.2015

When considered from the broadest perspective of ecosystem health and function, green roofs have the capacity to increase biodiversity and habitat continuity, moderate thermal fluctuations and maintain hydrologic processes in the built environment. At the level of the Colorado homeowner, these benefits are twofold in that they directly translate into energy savings, life-enhancing aesthetic improvements and an expanded scope of options for onsite stormwater management.

Regionally, the shifting climatic conditions of the High Rockies present quite the green roof design challenge. In a recent project in the Northstar Nature Preserve in Pitkin County, Colorado, Bluegreen had the unique opportunity to meet this challenge head-on and develop a contextually-rooted system featuring a native plant palette. Concerned with both performance and the vegetated dissolve of the home into the surrounding landscape, Bluegreen engaged in a rigorous process for Perpetuo to design custom seed mixes and plant pairings that facilitate ecological exchange with local floral and faunal communities, and secure long-term benefits for all residents of the Preserve, be they human, animal or vegetal.

Overlooking the Preserve, the site bears the marks of a lengthy period of alternation, but also holds in its topographic variation the ability to support an abundant array of plant communities. To best inform the development of custom seed mixes for the green roof and surrounding landscape, a number of plot studies were performed throughout the site to determine vegetative associations and proportions. Following thoughtful observation over several seasons, plug mixes were composed to enhance the existing structure and exclude a strong contingent of invasive species. In the case of the green roof, this mix included a dynamic layering of grasses to provide structure and orientation (e.g. Tufted Hairgrass, Thurber’s Fescue and Junegrass), and flowering perennials (e.g. Blue Flax, Rocky Mountain Penstemon, and Blue Harebell) that integrate subtle bands of blues.

Informed by soil and drainage requirements associated with the selected mix species, Bluegreen engaged American Hydrotech to provide the structural components necessary to make the green roof a success. From monolithic membrane to moisture mat, American Hydrotech’s suite of technical products laid the foundation for a fully-functioning – and long-lasting – green roof system.

For its novel integration of local plant performers, and advanced structural technologies, Bluegreen’s Perpetuo allows the dynamic ecologies of the High Rockies to be celebrated through seamless vegetative transitions. In its hybridized state, the green roof blends site and structure acting as a catalyst for an evolving landscape.