Degree Day

A unit that represents one degree of decline from a given point (such as 65oF) in the mean outdoor temperature of one day. Often used in estimating fuel requirements of buildings.

Demand Charge

The demand charge is based on the highest-demand interval each month.Sometimes also called Billed Demand, Demand Charges are based on a twelve-month historical record of each metered facility.

Design Intent Documentation

Design intent documentation helps building owners, architects, and engineers facilitate record-keeping and ensure that the owner’s and designer’s up-front vision and goals (for energy-efficiency or any other aspect of design) are achieved and periodically verified through performance measurement. Design intent documents evolve as the project moves through the milestones of programming, design, construction, into building occupancy and potential future renovation and retrofits.


A pipe or tube through which heated or cooled air flows.