Virginia Commonwealth University has installed green roofs, vegetation planted on top of a waterproofing system installed on a roof, on various buildings across campus. More extensive green roofs are installed on both the VCU Rice Rivers Center and the Pollak Building. Other buildings on campus with green roofs include the Academic Learning Commons, the Honors College Building and the Institute for Contemporary Art, which has green roofs on different parts of the building. Green roofs offer many benefits, including:
- Reduced heat island effect, due to the cooling effect of the green roof plants
- Reduced stormwater volumes, resulting from the rainwater-retention capacity of the plants and soil
- Reduced stormwater flow rates, resulting from the ability of the system to slow the flow of heavy rains through the system
- Reduced energy use, due to improved insulating characteristics of the system
- New wildlife habitat, primarily for insects and birds
- New passive recreational space, accessible to the entire VCU community
Pollak Building green roof
A vegetated roof, completed in fall 2011, was installed on the southeast-facing roof of the Pollak Building on the Monroe Park Campus. This green roof serves as an educational asset and has a variety of sustainable features. Most materials were sourced locally, within 500 miles of VCU, including a terrace paved in Pennsylvania Bluestone, a built-in wood bench crafted of Black Locust (a local, native and rot-resistant substitute for Teak), and salvaged steel planters – cut from various diameters of salvaged steel pipe found at S.B. Cox in the east end of Richmond.
Continue reading to learn more about the roof's features:
- The roof illustrates three different types of green roof planting strategies: conventional, meadow and native.
- The area of conventional green roof, the center portion of the roof, features a variety of low-growing sedum species, planted in three to four inches of growth media (sedum species, like cacti, are succulent plants, which can store water within their plant structures). Sedums in this area are non-native species, selected for their hardiness and ornamental characteristics.
- A second type of roof, a green roof meadow, occupies the outer, long edge of the roof. This section features somewhat taller plants, bedded in approximately six inches of growth media. Plants in this area are a mix of native and non-native species.
- The largest portion of the roofscape, closest to the building, features only plants native to Virginia – the first such green roof in the Commonwealth. Growth media in this section of the roof is approximately 12 inches deep, and can therefore retain more moisture than the other two sections of the roof.
The graphic below depicts the various types of plants you can find in the Pollak Building green roof.