In article ,
Jonathan Grobe wrote:

Anyone know of any plans on the internet to build
an energy efficient dog door (from the house to the
outside)? (My current one has plastic flaps and stays
open when the wind is blowing (and even if it is not lets
a lot of air through).

PS. Where do you get the heavy plastic that you find
in dog doors. What kind of plastic is it? (Mine is
starting to fall apart)

Why roll your own when you can buy one off the shelf? They make dual
pane, magnetic latch, etc. pet doors that are pretty high quality.