Yes, if the attic access door is within the living space and can open directly into the attic. Whether in a hot or cold climate, the access door should be treated just like an outside entrance door; it must be insulated and weatherstripped.
During cold and windy weather, heat loss and air leakage through uninsulated and non-weatherstripped ceiling openings is a major source of energy loss (resulting in higher heating costs). During the heat and humidity of the summer, where attic temperatures can double the temperature of the house, the uninsulated and non-weatherstripped access door will create heat gain (resulting in higher air conditioning costs). To increase comfort and reduce significant heat loss/heat gain through the access door and through infiltration around the door’s edges during the winter and summer, insulating and weatherstripping the attic access door is a must.
For information about how to properly insulate the attic access door visit “A Consumer’s Guide to Energy Efficiency and Renewable Energy” at: Attic Access Insulation