From inside the attic check for any openings holes or fenestrations into the knee wall surrounding area.
Seal attic hatch.
Diy sealing the attic hatch seal trim to ceiling create air tight seal between hatch and trim.
Hardware 2 small bungee cords to seal it tight.
Sealing the attic hatch or door finish up by sealing the access hatch with self sticking weather stripping.
If your hatch rests directly on the moldings add 2 1 2 inch wide stops around the opening.
How to insulate and air seal an attic access hatch.
Remove your existing attic hatch and measure its size.
Apply weather stripping to the door to create a seal.
Carefully pull down the finish trim.
The insulation will both slow heat loss and add ballast to the hatch to improve the seal at the weatherstripping.
The stops provide a wider surface for attaching the weatherstrip and a space to mount hook and eye fasteners.
Air seal the trim the first step is air sealing the finish trim and enclosure around the attic hatch.
Pray that the installer used finish nails and not say ring shank nails.