For a building program to be successful and sustainable, it is imperative that the program include an operating budget as well as the construction budget. When it comes to tenants leasing space in a building, the O&M budget is usually budgeted in cost per square foot and included in the annual lease fee. Fifteen to 20% of the cost of a building is first cost, and the remaining 80% or more of the cost to own a building is in the O&M of the building over its lifetime.

When designing a tenant retail space fitout within an indoor mall, the design engineer should refresh his memory relative to this Basis of Design by first going to ASHRAE Handbook 2015 Applications and read chapters 3 (commercial and public buildings), chapters 36 through 43 relative to building operation and management, chapter 59 (HVAC security), and chapter 61 (codes and standards).