The attic hatch should be sealed with removable sealant and insulated to minimize heat loss, and restrict air movement. This will reduce drafts and increase comfort in the home.
Windows often do not significantly impact the home’s overall energy-efficiency to the extent that is commonly believed, except for single-pane or broken windows. However, windows with storm windows, or double-paned windows, or windows that have been properly weather stripped, can reduce drafts and make a home more comfortable.
Doors need to be weatherstripped, much the same as windows. If the door isn’t fitting snugly, the weatherstripping should be fixed or added.
If drafts are significant, mark down where you find them. This can assist you in determining what weatherstripping needs to be fixed or added.