Does this foam expand any? If so by how much?

Thank you for the question. The OSI QUAD Foam Gun or Straw foam is a minimal expanding low pressure forma design ed for use in the cavity around windows and doors. Expansion is controlled by how much you are dispensing while pulling the trigger. Expansion is about 1 ½ times the amount dispensed. This is variable depending upon how well the can is shaken, temperature and humidity condition at the time is application and how hard you pull the trigger. If you are a first time user you should practice in a waste receptacle or box before starting the project.