Ventilated Double Window for the Preheating of the Ventilation Air Comparison of Its Performance in a Northern and a Southern European Climate

Table 1

Windows components physical properties.

	Heat transfer coefficient; (W/m^2·°C)	Solar absorptance; 𝛼	Solar transmittance; 𝜏
Sash	5.65	0.4	0
Glass	5.7	0.14	0.74