INCORRECTPhoto Source: Summerhill

ALMOST CORRECT Photo Source: Summerhill

Wall cavities may have piping, wires, and electrical boxes placed in them in different areas, and will require attention to properly cut and place the insulation.

Using batts in a wall cavity with piping:

The insulation needs to be cut to fit properly around the pipe without compressing the batt. Cutting a v-shape in the face of the batt will allow you to wedge the pipe into the batt so that the insulation surrounds the pipe.

For larger pipes it may be necessary to cut a piece of the insulation out. Remember that any reduction in the R-value of an exterior wall must be compensated for by increasing the R-value in an equally sized area elsewhere in the home.