The most preferred and energy-efficient glass dog door installation method, for these reasons…

Energy Efficiency - Thermal efficiency shows that this is the best place to install a dog door, because it's the least energy-efficient part of your home.

"The walls are the most insulated part of your home, so why cut a hole in them?"

Reversibility - You can save and store your insulated glass unit that is removed when installing your dog door in a new insulated glass unit and return it to your original door functionality.