Calculators
Urban greening factor
The Urban Greening Factor (UGF) is a tool developed by the Greater London Authority that evaluates and quantifies the urban greening proposed in new developments.
The UGF works by assigning a factor score to each surface cover type proposed in a planning application. Scores range from 1 for semi natural vegetation, through to 0 for impermeable sealed surfaces.
Instructions
- Use the greening factor from earliest stage of your design.
- Use a qualified landscape professional from the outset.
- The UGF should always be calculated on the total site area, equivalent to the red line boundary;
- Adjacent areas of land under the ownership or management of the applicant but not subject to the planning application must
not be included - Retained surface cover types should be included in the calculation.
Semi-natural vegetation
This is trees, woodland, species-rich grassland maintained or established on site
Wetland or open water
Semi-natural and not chlorinated, maintained or established on site
Intensive green roof
Green roof or vegetation over structure. Substrate minimum settled depth of 150mm
Trees in connected pits
Trees planted in connected pits. Must have a minimum soil volume equivalent to at least two thirds of the projected canopy area of the mature tree
Extensive green roof
Green roof with substrate of minimum settled depth of 80mm (or 60mm beneath vegetation blanket) – meets the requirements of GRO Code 2014
Flower-rich perennial planting
Rain gardens
Includes other vegetated sustainable drainage elements.
Hedges
line of mature shrubs one or two shrubs wide
Trees planted in pits
Trees with soil volumes less than two thirds of the projected canopy area of the mature tree.
Green wall
Wall –modular system or climbers rooted in soil
Groundcover planting
Amenity grassland
Species-poor, regularly mown lawn
Green roof
Extensive green roof of sedum mat or other lightweight systems that do not meet GRO Code 2014.
Water features
chlorinated or unplanted detention basins
Permeable paving
Extensive green roof of sedum mat or other lightweight systems that do not meet GRO Code 2014.
Sealed surfaces
concrete, asphalt, waterproofing, stone
Calcuation example for urban extension residential project
Residential Urban Greening Factor: 0.64
Total Site Area: 197,000sqm
Amenity grassland: 47%
(public space grass and garden grass areas)
Semi-natural vegetation: 27%
(natural mature trees and species rich grassland)
Sealed surfaces: 26%
(roads, driveways and building footprint)
