Ask Frost King: Do I Need to Add Anything to Make The Expanding Foam Tape Start Expanding?

Do I need to add or do anything to make the foam tape start expanding?
The answer is no, expandable foam tape only requires air to start expanding, so once the plastic has been removed, you'll start to see the tape grow right in front of your eyes.

[@glenn27521]

Bull. I got 1x1 foam tape and some expanded to about 7/8in fine but not what is advertised. Worse yet 2 days later and most is under 5/16 inch. It was about 3/16 in the roll a 1/8in of expansion and over 1/2 shy of what is stated. It's not like I can put it back in the roll for a refund.