How To Insulate Exterior Walls. Unless you remove the drywall you can't insulate from the inside that i'm aware of. When you say exterior walls it is somewhat confusing.
Insulation isn't just for the winter season, however. The only complication might be that, if you need to run the wires to the tv inside the wall and the exterior wall is insulated, it may be difficult to. Insulating basement walls is tricky without proper instruction.
Every old house needs special care!
I am currently in the process of insulating the exterior of my house. You can still put insulation inside existing walls if you know what to use. These solid wall properties can be insulated with external solid wall insulation. An exterior wall is simply a wall that has one of its surfaces on the outside of a building.