Many homes now have their attics insulated. However, often times the door or hatch to the attic is not insulated. No sense weatherstripping and sealing up your home only to have that warm air escape through the attic door. There are several ways to prevent that from happening.
One way is to install an attic door tent. This basically unfolds and forms a tent inside the attic to cover the access door. It looks like a reflective insulated tent. When you enter the attic, just push the tent to the side.
A better way to insulate that attic door would be to use an attic cover. This is an insulated door that goes over the attic door hatch. To make a good seal, you can caulk the edges to the floor of the attic. The door actually zips shut so it will form a nice air barrier between your living space and the attic. Installation is easy and should take you about 15 to 30 minutes to complete the job.