15 recommended ECM and O&M projects were developed for the Dirksen Senate Office Building through a Level 3 Energy Audit process. The assessment encompassed 10 floors and over 720,000 square feet of building space. The audit included photo documentation, HVAC zone documentation, lighting modeling, water use modeling, building simulation, and life cycle cost analysis.

The estimated cost to implement the recommended projects was $11 million with an associated savings of $1.4 million annually. The majority of the HVAC savings were associated with computer closet control upgrades and conversion to VAV with DDC controls. High energy costs were attributed to older controls that created a large degree of simultaneous heating and cooling.