An apparatus includes an end effector, a cartridge, and a buttress assembly. The end effector includes an anvil and a lower jaw. The anvil is configured to move toward and away from the lower jaw. The lower jaw is configured to receive the cartridge. The cartridge includes a housing, staples disposed in the housing, and a deck disposed over the staples. The buttress assembly is configured to be attached to either the anvil or the cartridge. The buttress assembly includes an adhesive layer, a film layer, and a buttress body. The adhesive layer is configured to adhere to either the anvil or the deck of the cartridge. The adhesive layer is attached to a first side of the film layer. The buttress body is attached to a second side of the film layer such that the film layer is interposed between the adhesive layer and the buttress body.