In most of the country insulation had become standard. It saves us money year round. Look to see that you have some in the attic and floors. You'll be surprised to find some houses have little or no insulation. Sometimes its blown or moved around in the attic, leaving holes. Is it falling out or tattered and hanging down in the crawl space? This may be a clue the crawl space is wet. Don't touch the insulation, many types will make you itch. There is a Urea Formaldehyde Foam Insulation that looks like soap suds and may give off formaldehyde fumes. An air quality test may be wise if your dreamhome has this type of insulation.