As you may well know, heat will naturally transfer from a warmer environment to a colder one. This means that during the summer, when you are running your air conditioner to keep the interior of your home cool, the intense heat outside is going to try to infiltrate your home. Likewise, during the winter the heat you use to keep your house warm is going to try to transfer into the colder environment outside. In either case, it is your insulation which is responsible for stopping this natural heat transfer.
In order for your insulation to do its job properly and as effectively as possible, it is necessary for it to be of the right R–value. The R–value of insulation is a number which denotes the efficiency with which that insulation stops the transfer of heat. If the R–value of your insulation in Los Angeles, CA is too low, it will allow heat to pass through to freely. If your insulation is too efficient, though, you may encounter other problems, including issues with stale air. Striking the right balance is a must, and only a trained professional can ensure that the right type of insulation is used.