 You don't have good gas-getting material to keep the moisture and the wind-driven rain from coming through the window. You can tell a difference in the heating and cooling bills when you have a good quality window product. The walls are going to be pretty good. I mean, any house that was built since 1973 requires a certain amount of insulation. The sidewalls, those are 11 back then. It was really easy to get the insulation out of my 1936 phone. I know they're walnut. This was an internet.