Green roofs are an increasingly popular alternative to cooling roofs. According to a review published in 2008, green roofs can provide annual energy cost savings of up to 50%, depending on the climate. The cool roof design reflects sunlight and reduces heat transfer to the interior of the building. Cooling roofs are usually white or light colored. However, the roof is in favor of vegetated surfaces. The name "green roof" is fitting, given the greenery; however, the name refers to the environmental impact.
Typically, green roofs are implemented in locations such as the high rainfall Midwest and East Coast. However, the importance of reducing heat loads inside buildings for sustainable development in cities such as Phoenix and Las Vegas cannot be overstated, reducing energy costs. University of Las Vegas researchers Milburn Fernandez-Gonzalez, Jones, Solano and Martinez-Wong conducted a study on greening roofs to demonstrate the benefits of green roofs in desert environments. Research quantifies the temperature impact of a green roof on residential buildings in a desert environment.
The results of this study help developers determine which roof types reduce energy consumption during the day and reduce energy consumption. To conduct this study, researchers recorded temperature data with Onset's HOBO® data loggers. The researchers placed data loggers in eight different pods to simulate three different roof types: insulated cool, insulated green, and non-insulated green. One weather station U30-ETH-000-05-S100, U30-ETH-000-10-S100, U30-ETH-VIA-05-S100, U30-ETH-VIA-10-S100, U30-GSM-000-05 -S100, U30-GSM-000-10-S100, U30-GSM-VIA-05-S100, U30-GSM-VIA-10-S100, U30-NRC-000-05-S100-000, U30-NRC-000 -10-S100-000, U30-NRC-VIA-05-S100-000, U30-NRC-VIA-10-S100-000, U30-WIFI-000-05-S100, U30-WIFI-000-10-S100 , U30-WIFI-VIA-05-S100, U30-WIFI-VIA-10-S100 are also installed to measure precipitation S-RGB-M002, wind speed S-WSET-A, temperature S-TMB-M002 to monitor the evapotranspiration influence so that the plant survives.
Research data loggers (RX3000) (RX3001-00-01, RX3002-00-01, RX3003-00-01) with thermistor temperature sensors S-THB-M002 installed at two locations on the west wall of each pod— — directly under roof decks and soil layers. Researchers begin plotting data using HOBOware® Pro software and then export data to Microsoft Excel for more detailed analysis.
According to previous green roof studies, 27% of solar radiation reflects S-LIB-M003, S-LIA-M003, S-LWA-M003 plant material, 60% is absorbed plant material, and 13% penetrates the soil. Due to the current research on green roofs on the roofs of barren hills the vegetation on the roofs creates a barrier from the sun, reducing the penetration of solar radiation into the soil in green roofs than in cooler roofs. During the day, the pods on the green roof keep it from getting less heat, making it cooler inside the cool roof.
On average, non-insulated green roofs had the hottest and coolest daytime temperatures and the coolest nighttime temperatures, while insulated cool roofs had the hottest daytime temperatures and the coolest nighttime temperatures.
Based on the results of this study, non-insulated green roofs were more effective than cooling roofs and insulated green roofs for reducing daytime energy consumption. To reduce energy consumption at night, insulating the roof is great and insulating the green roof is a second best. Non-insulated green roofs do not do justice in this category because they act as heat sinks, heating the interior space at night.
Other benefits of green roofs include reduced urban heat island effect, extended roof life, more green space, cleaner air and water, and less noise pollution.
