To insulate the ceiling with batt, roll or foam board insulation, friction-fit cut pieces between the rafters or ceiling studs or hold faced batts or pieces in place with staples.

The first, installing batt insulation, is definitely a do-it-yourself job. The second, spraying expanding foam insulation between the joists, is a job best left to the pros.

There must be a better way than pricey spray-foam insulation to make a home more energy efficient.

Polyiso is a closed-cell, rigid foam board insulation that typically comes in 1, 2, and 4 inch thickness. THERMAX™ and Dow “blue board” are the two most common types of polyiso insulation.