Sustainable design for a subtropical green roof with local, recyclable substrates and native plant species
As sustainable development becomes the norm, such innovations as the green roof are becoming more commonplace around the world. However, designs tailored for specific climatic regions are still in their infancy. Vegetation and substrate are elements of a green roof that need to be suited for each microclimate and not universalized. Furthermore, sustainable design of a green roof must be based not only on the nature of its benefits, but on its individual components, as well. The use of local and recycled materials needs to be included as a means of minimizing environmental impacts and improving local economies. The goal of this research was to test for vegetation and substrate suitability for a subtropical climate green roof found in East Texas based upon tenets of sustainable design focused on minimizing environmental impact. Three timber frame plant boxes measured at one square meter were constructed with various substrate depths. Each box contained a different substrate: local topsoil with compost, expanded shale with compost, and recycled crushed concrete with compost. The boxes were further subdivided into four plots with plantings of Lenophyllum texanum (coastal stonecrop), Buchloe dactyloides (buffalograss), and Bouteloua gracilis (blue grama). Each box contained varying substrate depths within the individual plots: 4 inches, 6 inches, and two plots of 8 inches. Results of the study supported successful native plant establishment and the use of local, recycled substrates. These findings give information for sustainable design of green roofs in East Texas and other similar subtropical climates.
life cycle assessment
Huerta, Angelica (2011). Sustainable design for a subtropical green roof with local, recyclable substrates and native plant species. Available electronically from