One of the most common sources of drafts and cold air in a home is a leaking attic entry hatch. They are often out of sight and out of mind but can lead to a lot of chilly nights and increased heating costs.
As with any drafty situation, the first thing to look for is a source of air leakage. When air can move from one area to another it takes heat with it. This is a good thing for hot air blowing out of a heating duct register but not ideal when that same heated air is moving in to the attic or outdoors.
From the thermal images and with visual inspection of this attic hatch it appears that the weatherstripping is inadequate. There is pretty good insulation over the center of the hatch but there is obvious air movement around the perimeter. Warm air from the house is leaking in to the attic which increases heating costs and decreases comfort in the home.
Brian Jovag, owner of Jovag Home Inspection.