“ Idle reduction is a fundamental practice in fuel and maintenance cost reduction.”

An owner/operator

Executive Summary

Extra cab or sleeper insulation is a baseline technology that enhances the efficiency of other idle-reduction technologies by decreasing the energy demand of the heating and cooling system. There are a wide range of insulation options for improving fuel economy: the original equipment manufacturer can include additional insulation when the vehicle is built (prior to the installation of the interior trim) or the fleet or owner/operator can add a thicker windshield, bunk or windshield curtains, or solar-reflective interior window coverings.


Introduction to Idle Reduction
Best Practices

Almost all of the other idle-reduction technologies operate more efficiently with the addition of extra cab/sleeper insulation.

  • Extra insulation in the cab and sleeper plus an insulating sleeper curtain and/or window covering will help retain heat and air conditioning generated by a diesel APU, allowing the APU engine to run less.
  • Extra insulation is also recommended for use with a battery HVAC system.
  • When relying on automatic engine start/stop systems, which can’t get the sleeper cool enough in hot weather, add thermal window curtains.
What Others Are Saying
Decision-Making Tools

There are already a wide variety of payback calculators for any given type of idle-reduction system. In an effort to meet the industry’s need for more information, we have also developed a high-level payback equation to aid fleets in choosing the right combination of technologies.

Decision-Making Tools


Most truck manufacturers offer additional insulation as an option to truck buyers.


Extra cab or sleeper insulation is a good starting point for any idle-reduction solution. Specifying the truck with the highest-level insulation package available from the truck manufacturer will help ensure maximum efficiency for any heating or cooling option the fleet selects. Expect to see continued advancements in cab sealing and insulation including new developments in chemistry and materials engineering along with improvements in the application of insulation and sealing during the vehicle manufacturing process. There may also be advanced technologies developed for window glass and window curtains to provide a better barrier against solar loading.