This 25″ x 54″ x 11″ insulating stair cover is a piece of the puzzle of weatherizing your home. It slows air transfer from your attic to your home, and stops insulation from falling into your home when the attic is accessed. Fits most openings up to 25″x54″. We manufacturer this cover a few inches larger than needed to accommodate building tolerances. If your opening is too small, simply fold the edge over and staple for an airtight seal. Easy access to your attic with a zipper. Easy to install, all you need is a staple gun. You can use caulk around the edges for an extra seal if you like, but its not necessary. Fits most openings up to 25″x54″. We manufacturer this cover a few inches larger than needed to accommodate building tolerances. If your opening is too small, simply fold the edge over and staple for an airtight seal.