Pound the hatch door's jamb back into place using a rubber mallet if the door’s trim begins to come loose.
Wedge the thin end of wooden shims along the perimeter of the hatch door between the jamb and the frame. Insert the shims into the gaps under the hatch door's stair ladder pivot arms and near the hinges.
Hammer the shims tightly into the gaps by tapping each shim's wide end with the rubber mallet. Hammer the door jamb back into place using the mallet.
Install wood screws through the shims and into the hatch door jamb using a drill with a Phillips screw tip. Tap the door trim back into place firmly against the ceiling with the rubber mallet.
Lubricate the hatch door's pivot hinges if you have problems opening and closing the door. Find the nozzle that came with the silicone spray can, and put it on the can. Squeeze the nozzle to apply the silicone spray to the pivot hinges. Dampen the hinges with the spray, working it into the interlocking areas.
Open and close the hatch door to verify that it moves smoothly.
Tighten screws and bolts holding the hinges in place on the hatch door if they rattle when you open and close the hatch. Tighten the screws first with a screwdriver, and then tighten the nuts around bolts with appropriately sized wrenches. Work on one side of the hatch door's stairs at a time.
Determine which size of foam weatherstripping to use to seal gaps around a hatch door's edges. Use weatherstripping with a width and depth that adequately fills the gap between the edge of the hatch door and the ceiling. For example, use 1/4-inch foam strips for small gaps and ½- to ¾-inch foam strips for large gaps.
Measure the length of each side of the hatch door with a tape measure. Unroll the foam weatherstripping. Measure and mark the weatherstripping to the measurements you took, and cut the weatherstripping to those lengths to fill the gaps.
Peel the paper backing from the weatherstripping you cut, and stick the weatherstripping to the corresponding edges of the hatch door. Press the weatherstripping to secure the adhesive side of each piece against either the hatch door or ceiling side of a gap.
Close the hatch door, and verify that the foam weatherstripping fills all the gaps around the edges. Add weatherstripping if necessary.