Cup of Joe - Airtightness - How did we get here?

Ancient proverb: To control air, you must enclose air. Brilliant!
Why do we prefer air-control layer instead of air barrier?
How did we come to define airtightness?
Why do we call them blower door tests?
Why do we depressurize?
Why did we choose 50 Pascals?
Find out the answers here.
If you are so excited to learn this stuff, you just can't stand it, consider signing up for one of our seminars today!