How long does Kilz last?

How long does Kilz last? How long Kilz lasts depends on whether referring to shelf life in can or longevity once applied. In can, unopened Kilz primer typically lasts about 2 years if stored properly in cool dry place with lid sealed, not frozen, though some cans last longer. Once opened, if sealed well, it may last about 1 year before thickening or spoiling. Always check for foul smell, lumps, or not mixing. Once applied to surface and topcoated with paint, Kilz primer itself can last for many years, essentially as long as paint job lasts, 5 to 10 years or more interior, helping prevent stains and peeling. Kilz as stain blocker remains effective under paint for years unless surface damaged by water or fire again. Kilz Original oil-based provides long-lasting odor and stain seal. Durability depends on surface prep, topcoat quality, and exposure. For example, Kilz on drywall under latex paint can last 10 years interior. Exterior use may last less due to weather. So shelf life is about 2 years unopened, and once applied with paint, its sealing benefit lasts for years as part of paint system.