MATERIAL:ROOFVEGETATION
EcoRoof model, plant layer plus soil layer Implemented by Portland State University (Sailor et al., January, 2007) only one material must be referenced per simulation though the same EcoRoof material could be used in multiple constructions. New moisture redistribution scheme (2010) requires higher number of timesteps per hour (minimum 12 recommended).
Name
Type: alphanumeric
Height of Plants
Type: real number
The ecoroof module is designed for short plants and shrubs.
Unit: m
Maximum: 1.0
Default: .2
Leaf Area Index
Type: real number
Entire surface is assumed covered, so decrease LAI accordingly.
Unit: dimensionless
Maximum: 5.0
Default: 1.0
Leaf Reflectivity
Type: real number
Leaf reflectivity (albedo) is typically 0.18-0.25
Unit: dimensionless
Minimum: 0.05
Maximum: 0.5
Default: 0.22
Leaf Emissivity
Type: real number
Minimum: 0.8
Maximum: 1.0
Default: 0.95
Minimum Stomatal Resistance
Type: real number
This depends upon plant type
Unit: s/m
Minimum: 50.0
Maximum: 300.
Default: 180.0
Soil Layer Name
Type: alphanumeric
Default: Green Roof Soil
Roughness
Type: choice
(VeryRough, MediumRough, Rough, Smooth, MediumSmooth or VerySmooth)
Default: MediumRough
Thickness
Type: real number
Thickness of the soil layer of the EcoRoof Soil depths of 0.15m (6in) and 0.30m (12in) are common.
Unit: m
Maximum: 0.7
Default: 0.1
Conductivity of Dry Soil
Type: real number
Thermal conductivity of dry soil. Typical ecoroof soils range from 0.3 to 0.5
Unit: W/m-K
Minimum: 0.2
Maximum: 1.5
Default: 0.35
Density of Dry Soil
Type: real number
Density of dry soil (the code modifies this as the soil becomes moist) Typical ecoroof soils range from 400 to 1000 (dry to wet)
Unit: kg/m3
Minimum: 300
Maximum: 2000
Default: 1100
Specific Heat of Dry Soil
Type: real number
Specific heat of dry soil
Unit: J/kg-K
Maximum: 2000
Default: 1200
Thermal Absorptance
Type: real number
Soil emissivity is typically in range of 0.90 to 0.98
Maximum: 1.0
Default: .9
Solar Absorptance
Type: real number
Solar absorptance of dry soil (1-albedo) is typically 0.60 to 0.85 corresponding to a dry albedo of 0.15 to 0.40
Minimum: 0.40
Maximum: 0.9
Default: .70
Visible Absorptance
Type: real number
Maximum: 1.0
Default: .75
Saturation Volumetric Moisture Content of the Soil Layer
Type: real number
Maximum moisture content is typically less than 0.5
Maximum: 0.5
Default: 0.3
Residual Volumetric Moisture Content of the Soil Layer
Type: real number
Minimum: 0.01
Maximum: 0.1
Default: 0.01
Initial Volumetric Moisture Content of the Soil Layer
Type: real number
Maximum: 0.5
Default: 0.1
Moisture Diffusion Calculation Method
Type: choice
(Simple or Advanced)
Advanced calculation requires increased number of timesteps (recommended >20).
Default: Advanced