# UWC Green Roofs¶

Warning

This node is currently under testing

The UWC green roof nodes supports the placement of green roofs at lot scale. The node will update the lot scale urban water cycle to consider a green roof as part of the hydrological model as well as an update to the urban heat models assuming the green roof functions as irrigated grass surface. Green roofs are assigned to fraction of randomly selected buildings within the spatial extend of the user specified area.

In the hydrological model the green roof is simulated as pervious surface considering, surfaces runoff, infiltration and evapotranspiration. The streams for surface runoff and infiltration are combined and replace the roof runoff stream.

The parameters for the green roof can be defined using soil templates. The default values are shown in table uwc_green_roof_soil_profile

Green Roof Default Parameter

Parameter

Default

initial soil storage (m)

0.3

infiltration capacity (m)

0.2

infiltration exponent (-)

1

initial groundwater store (m)

0.01

daily recharge rate (-)

0

daily drainage rate (-)

0

daily deep seepage rate (-)

0

soil store capacity (m)

0.03

field capacity (m)

0.02

## Parameter¶

Name

Type

Description

Default

Values

fraction of parcels with a green roof

DOUBLE

fraction

0.1

0-1

Green roof soil parameters

INT

2

2-100