People who tear their walls down to the studs during a remodel are often amazed at what they find, and some of them might find absolutely nothing as the walls come down. Insulation was not a large factor in the past, so it was often a step that was skipped. As people became more aware that adding insulation could help them save money, they tossed in whatever was near at hand. Examples of this type of insulation vary from local newspapers being balled up to excess cloth or wadding that was put in the walls. Modern insulation is more like a blanket for the house, and its function is to keep each room as cozy as the setting on the thermostat.
The decision to add insulation during a remodel is often one that contractors will mention, and they have plenty of recommendations these days. There are several types of batting insulation, and each one has its own energy rating. These do not necessarily need to be installed by a professional, but they should be added during any remodel to lower overall costs after the work is complete.
Foam boards are another type of insulation that can be added during a remodel, and they do not necessarily need to be installed by a contractor. It might be best to consider hiring a professional because they must be covered with fire safety rated surfaces on the interior of the home, and any used on the outside must be waterproofed.
For those who want to insure every crack and crevice in their home will not raise their energy costs, spray foam insulation is available. These must be installed by a professional, but most contractors can do it or recommend someone who is qualified. They have the highest energy efficiency ratings, but they also come with the greatest cost.