Steven ChuObama’s former Energy Secretary & Nobel Prize Winner pioneered the study of Urban Heat Islands (UHIs).
Some people believe that nuclear power is the answer to climate change, others have proposed green technologies such as wind or solar power, but Barack Obama's top man on global warming has suggested something far simpler
White roofs or Grey roofs
Not Green, Blue, Red or Yellow Roofs...
Average temperature on a hot summer day will be seven degrees warmer in urban areas that surrounding rural areas.
Roofing takes up a lot of surface area in urban areas, but roofing is not often considered a source of urban heat because it is “out of sight, out of mind.” Yet colored roofing accounts for 38%, or almost three degrees, of the seven degree difference associated with UHIs
Installation of Greencor roofing during initial construction or when re-roofing, offers immediate benefits, not only toward mitigation of UHIs but also as energy savings.
|Properties||Metal Sheets||Greencor Sheets||Inference|
|Material||Galvanised Iron||Cement, Fly Ash, Synthetic Fibre||Greencor ensures zero maintenance Resistance to natural weathering / corrosion|
|Sound||High Noise Pollution||Zero Noise Pollution||Greencor ensures calm and quiet environment|
|Heat Difference (0oC)||Absorbs heat, hence warmer||Keeps the interior 5oC cooler in summer and warmer in winter||Greencor reduces and keeps internal temperature cooler than ambient temperature.|
|Lightning and Power||Conducts & Affects||Does not conduct and aﬀect||Greencor is unaffected by lightning and live power wire hence ensures a safe environment.|
|Thermal Conductivity (λ)(ASTM C177)||20 W/mK||0.18 W/mK||Greencor has very low thermal conductivity property which results in lower conductance of heat or cold. This results in better living environment.|
|Load Bearing Strength||--||3300 N/m||Greencor has excellent load bearing strength|
|Non- combustibility||Poor||Excellent||Greencor is non-combustible / Fire resistant|
|Life||8 Years||40 Years||Greencor is more durable when compared to all metal sheets Metal sheets tend to corrode and rust.|
|Chemical Resistance||Poor||Excellent||Greencor has excellent chemical resistance.|
|Vapour Permeability||Poor||Good||Greencor prevents condensation because of breathability.|
Cities can be 2° to 8°F warmer than surrounding areas due to dark materials, roads and roofs including roofs, which absorb the sun’s light energy as heat during the day and release it at night as heat. This phenomenon prevents air from cooling down at night and results in higher temperatures being maintained longer. By immediately reflecting solar radiation back into the atmosphere and re-emitting some portion of it as infrared light, Roofs like Greencor result in cooler air temperatures for urban environments.
Greencor roofs, through mitigation of the urban heat island effect reduce ambient air temperatures, and improve air quality. Smog is created by photochemical reactions of air pollutants and these reactions increase at higher temperatures. Therefore, by reducing the air temperature, Greencor roofs decrease the rate of smog formation.
Lower ambient air temperatures and the subsequent improved air quality also results in a reduction in heat-related and smog-related health issues, including heat stroke and asthma and worker productivity.
Because Greencor Roofs reduce air-conditioning use during the day’s hottest periods, the associated energy savings occur when the demand for electricity is at its peak. Therefore, Greencor roofs reduce stress on the energy grid during hot summer months and help avoid shortages that can cause blackouts or brownouts.
Greencor roofs directly reduce air conditioning use for buildings by reducing heat gain in the building below, but they also indirectly reduce air conditioning use in urban areas by helping lower ambient air temperatures. Cooler daytime temperatures mean that buildings use less air conditioning. In turn, this results in a reduction in the CO2 emissions from electricity generating power plants.
|Length (m)||1.5, 1.75, 2.0, 2.75, 3.0||+/- 10|
|Width (mm)||1050||+10, -5|
|Laid Width (half corrugation)||1010||+10, -5|
|Pitch (mm)||146||+6, -2|
|Depth (mm)||48||+3, -5|
|Thickness (mm)||6||± 10%|
|Out of squareness of sheets (mm)||Less than 10||N/A|
|Sheet weight (Kg/m)||13.1||---|
|Number of corrugation||7||Nil|
|Weight of 100m2 as laid*|
|a) With 3 m sheet||1.42 Tonnes||---|
|b) With 1.5 m sheet||1.52 Tonnes|
|Side Lap (min)||40 mm|
|End Lap (min) (for lower slopes use lap sealants or increase end laps)||150 mm|
|Actual Cover of 3 m sheet as Laid (allowing for loss by side lap of 40 mm and end lap 150 mm)||2.55 sq.m|
|Sheeting require of 100 sq.m as Laid|
|a) using 3 m sheets with side and end lap loss||109.38 sq.m|
|b) using 1.5 m sheets with side and end lap loss||115.51 sq.m|
|Purlin Spacing for Side Cladding||1400 mm|
|Runner Spacing for Side Cladding||1700 mm|
|Maximum free over at Eaves||300 mm|
|Greencor sheets must be lifted at both ends|
|Greencor sheets must be stored on a dry, smooth and stable platform|
|Greencor sheets must be stored to maxium number of 40 per stack height|