I have improvised a poor man’s insulation device for a contact sensor in a wooden gate - used. 1/2 wood spade drill and drilled a few holes to form a rounded rectangle roughly the shape of the Iris contact sensor. Put the sensor in a snack ziploc bag (hell yeah lol) and pushed the air out of the bag, zipping it up. Then I wrapped the bag around the sensor and shoved it into the drilled hole. Did that about a year ago. I occasionally replace the bag after a few battery changes, simply because I have bags in excess LOL
My patio screen contact sensors are wrapped in kitchen cling wrap then taped around the edge once, then front to bottom once, then taped with double tape to the screen door frame. In the rain, never a problem, have not rusted on the inside, never found water in them. Gas? Hmpff…