Theoretical Analysis and Comparison of the Thermal Performance, Construction Costs, and Maintenance Complexity between a Conventional and an Intensive Green Roof

Table 2

Thermal resistance of layers of a conventional flat roof (the table is structured by authors upon data collected from cost estimate for the building under construction).

Material type	Thickness	Thermal conductivity	Thermal resistance
	d (m)	λ (W/mK)	R (m^2K/W)
Ceramic tiles	0.02	1.3	0.02
Geotextile	0.003	0.19	0.02
ECB-based polymeric waterproofing tape	0.002	0.26	0.01
Thermal insulation, foam glass in hot bitumen	0.18	0.045	4.00
Synthetic felt geotextile, vapour barrier	0.01	0.19	0.05
Lightweight concrete	0.13	0.55	0.24
Reinforced concrete (roof deck)	0.30	2.6	0.12