Why we shiver inside an old passively oriented Building?
Why during winters, does it feel colder inside an old passively built habitat? And what can improve it?
Yes, at present the Delhi NCR is undergoing extreme heat, the corona epidemic has forced us all to stay indoors. One is lucky to reside in a passively oriented low-rise habitat with grown-up trees. But those in high-rise apartments without passive orientation have to bear the burnt.Passive building is designed to stay cooler in summers and warmer in winters. The excel simulation shows why an old passively oriented house with wooden or old steel doors and windows would feel colder. Here I assume that the passively built building has old, leaking door and window elements. Simulation is based on the first principle that the cold air is heavier than warm air and passive orientation enhances the temperature differential between the sunny and shaded sides.
Typical specifications followed a couple of decades back allowed for air gaps that permitted dimensional changes on account of seasonal thermal and air humidity variation. We had not entered the Anthropocene and climate-induced weather extremities had not penetrated human consciousness.
Illustration taken from CPWD Manual on Door and Window Details for Residential Buildings https://cpwd.gov.in/Publication/manualdw.pdf below shows that 10 mm space below the door was a norm.