One of the first places where you will notice a difference in temperature is the garage. If you have a connecting door that goes from the house to the garage, every time you open that connecting door you will find that there is an oven-like blast of hot air which will bring the temperature up in your house and force the air conditioning to work over time. A good way to avoid this is to limit the frequency you go into the garage during the hottest hours, as mentioned above.