Table 4. Properties of pavement elements related to biotope area ratio

Type ID	Space type	Family name*	Underground condition	Soil depth	Permeability coefficient**	Weight***	Material layers
1	Natural ground green area	• Natural ground green area	Natural			1.0	• Greenery material on the top
2	Artificial ground green area	• Artificial ground green area	Artificial	90cm≦depth		0.7	• Artificial soil, permeable sheet, aggregate layer
				40cm≦depth<90cm		0.6
				10cm≦depth<40cm		0.5
3	Water space	• Water impermeable	Artificial			0.7	• Gravel, soil, felt, EPDM sheet
4	Partial pavement	• Stepping stone paving	Natural			0.5	• Stepping stone, sand, rubble
			Artificial			0.5×0.7
5	Permeable pavement on entire surface	• Permeability block paving • Masato paving • Sand paving	Natural		Class I	0.4	• Permeability block paving (Ascon, sand, rubble) • Masato paving (Rough sand, rubble) • Sand paving (Sand)
					Class II	0.3
			Artificial		Class I	0.4×0.7
					Class II	0.3×0.7
6	Pavement with cracked surface	• Wood deck pavement	Natural			0.2	• Wood deck pavement (Hardwood, concrete, rubble)
			Artificial			0.2×0.7
7	Linked area to rainwater storage & infiltration facilities	• Linked area to rainwater storage & infiltration facilities				0.3
8	Pavement area	• Pavement				0	• Asphalt, rubble, sand

The list of the family names is only for this specific case. It could be added and modified
Permeability coefficient: Class I ≧ 1mm/sec, Class II ≧ 0.5mm/sec
The weights and application of space types based ⌜Application guidelines on biotop area ratio (Ministry of Environment, 2016) ⌟