Insulating your house stops the flow of heat into and out of your house. The warm air wants to equalize the temperature, so it is going to try to move to where the air is cooler so that the air is a uniform temperature. In the summer, that means that you aren't letting the cold out, you are letting the heat in. That warm air wants to come in and make the temperature the same. Insulation stops this by letting blocking all the places that let the heat transfer happen. You want to make sure that you get the most efficient insulation possible. In order to do that, you need to understand how insulation efficiency is rated.
The R-value of an object describes how thermally resistant is. Thermal resistance means how hard it is for heat transfer to occur. The R-value also includes the thickness of the object. Generally the thicker an object is, the more thermal resistance it has. R-value is always expressed in numbers, such as R-19 or R-6. When you are building your home, each component has its own R-value, but when it comes together into a wall, those components are added together to get the full R-value.
R-Value and Insulation
When you are shopping around for insulation, you want to look at the R-value. You not only want to check the R-value of the particular insulation, but you will also want to find out what the R-value per inch will be in a finished setting. For example, you may get some insulation that has an R-value of 25. If you double up the thickness, you have the potential of having R-50 insulation. However, if you have had to compress the insulation in order to fit it into a particular space, you may lose some of the insulation's R-value of 25, so it won't double the total R-value, but it will increase it. Part of the reason you will lose the full R-value of the insulation when it is compressed is that part of the way that insulation works is that it traps air in small cells and chambers. Air acts as a good insulator. When the insulation gets compressed, there is less space for the air to be, causing the insulation to be slightly less efficient.
When you need to insulate your house, there are things that you need to look at. The R-value of the insulation, and how much R-value per inch you will get, will give you a good idea of how efficient it is. You can also reach out to an insulation specialist such as Energy Home Insulation Inc for more details.