Is Indoor Pressure the Same as Outdoor Pressure?

[vettel1993]

1. Is the pressure inside a building equal to the outside? Is there a very tiny difference?
What about air-tight room?

Homework Equations

The Attempt at a Solution

 

[PWiz]

If the pressure was different, what do you think would happen? Have you tried crushing a juice pack by sucking some air out?

 

[paisiello2]

It would depend on how "open" the building was.