Substandard Insulation

The International Energy Conservation Code recommends a ceiling R-Value of 38 for Indiana.

In order to obtain this minimum R-Value, attics should have at least 12 inches of cellulose or fiberglass insulation.   Unfortunately, it is rare that attics have enough insulation in the homes that I inspect. More often than not, the depth of insulation ranges from 4 to 8 inches.  The good news is, adding additional insulation is usually not too difficult and the investment can yield savings by way of reduced energy bills.

The two most common options for adding additional insulation to your attic are batts or blown in.  Batts are like blankets of insulation that come in a roll. They are available in different thicknesses (R-Values) and can be rolled out over the top of the existing insulation. 

Blown in insulation comes in bundles that is usually installed with a machine that blows the insulation through a hose allowing it to be dispersed evenly throughout the attic.  Many home improvement stores allow homeowners to borrow or cheaply rent the machine with the purchase of insulation. 

There are a few things to consider before adding insulation.  Vapor barriers, which can be paper or plastic, should always be adjacent to the warm side of the structure.  Sometimes insulation is installed incorrectly with the paper/plastic facing up in the attic. In this case, the paper/plastic should be removed before adding additional insulation.  Leaving the vapor barrier sandwiched between layers of insulation can trap moisture making the insulation less effective and possibly allowing mold and mildew to flourish. 

Another thing to consider and investigate is attic ventilation.   Many attics draw in air from the eaves through vented soffits. These soffits should not be blocked with insulation.   Soffit vents are readily available and will keep insulation away from the eaves while allowing adequate airflow.

Adding insulation to your attic can be a good do it yourself project with a little preparation and knowledge before you start.  If you plan to hire the job out, make sure you ask the contractor how they will handle vapor barriers and attic vents.