This data sets the foundation for how commercial LED lights can dramatically reduce energy costs for different building types relative to the standard ASHRAE watts per sq ft. LED lights can reduce the w/sq ft. by 50% or more. The following information is useful for lighting and energy professionals in comparing savings with LED tubes and LED fixtures over existing and allowed averages across different property types.   ASHRAE/IES 90.1 Lighting power allowances using the Building Area Method.
Building Type Maximum Lighting Power Density (W/sq.ft.) Allowed Per Version of the ASHRAE/IES 90.1 Standard
1989 1999/2001 2004/2007 2010
Automotive Facility 0.96 1.5 0.9 0.982
Convention Center 2.07 1.4 1.2 1.08
Court House 1.44 1.4 1.2 1.05
Dining: Bar Lounge/Leisure 1.37 1.5 1.3 0.99
Dining: Cafeteria/Fast Food 1.37 1.8 1.4 0.9
Dining: Family 1.37 1.9 1.6 0.89
Dormitory 1.15 1.5 1 0.61
Exercise Center 2.07 1.4 1 0.88
Gymnasium 2.07 1.7 1.1 1
Healthcare Clinic 1.44 1.6 1 0.87
Hospital 1.44 1.6 1.2 1.21
Hotel 1.15 1.7 1 1
Library 1.29 1.5 1.3 1.18
Manufacturing Facility 0.96 2.2 1.3 1.11
Motel 1.15 2 1 0.88
Motion Picture Theater 2.07 1.6 1.2 0.83
Multi-Family 1.15 1 0.7 0.6
Museum 2.07 1.6 1.1 1.06
Office 1.26 1.3 1 0.9
Parking Garage 1.03 0.3 0.3 0.25
Penitentiary 1.44 1.2 1 0.97
Performing Arts Theatre 2.07 1.5 1.6 1.39
Police/Fire Station 1.44 1.3 1 0.96
Post Office 1.44 1.6 1.1 0.87
Religious Building 2.07 2.2 1.3 1.05
Retail 2.25 1.9 1.5 1.4
School/University 1.29 1.5 1.2 0.99
Sports Arena 2.07 1.5 1.1 0.78
Town Hall 1.44 1.4 1.1 0.92
Transportation 2.07 1.2 1 0.77
Warehouse 1.03 1.2 0.8 0.66
Workshop 0.96 1.7 1.4 1.2
Source: http://lightingcontrolsassociation.org/ashrae-releases-90-1-2010-part-1-design-scope-administrative-requirements/

ASHRAE 2008 Report: http://www.energycodes.gov/sites/default/files/becu/lighting07.pdf