About 40% of feeling comfortable is attributed to the level of radiant heat exchange between your body and your surroundings. Proper insulation cuts down on this exchange of radiant heat, which makes your home—and you—much more comfortable. Insulation ensures that conditioned air stays in, and the weather stays out. You pay a lot of money to condition the air in your home through your heating, ventilation, and air conditioning system (HVAC). Poor insulation allows that conditioned air to escape your home, while letting outside air in, which means you are wasting a lot of money on inefficient heating and cooling.