a double bag vacuum insulation panel for use in a temperature assured shipper made in a steam chest molding machine is provided . the double bag vip comprises a porous core , a heat sealable inner envelope and an outer bag . the inner envelope is made from a substantially gas impermeable first material having a first thickness and defines an interior having a pressure of less than or equal to about 30 millibar . the outer bag is made from a substantially gas impermeable second material having a second thickness . the outer bag encapsulates the inner envelope . the double bag vacuum insulation panel has an r value of at least about 28 hr - ft 2 —° f ./ btu - in and the r value drops less than about 10 % after being exposed to a temperature of up to 95c for up to 7 seconds .