System and methods for assessing whole-building thermal performance

A system for characterizing a thermal efficiency of a structure based upon an inside temperature of the structure, as provided by a measurement device, and periodic outside temperature measurements proximate the structure recorded in a first database, the system comprising:

• a database configured to receive and store, as inputs, the inside temperature and the periodic outside temperature measurements and to correlate the inside temperature and the periodic outside temperature measurements;
• and
• a processor in communication with the database and capable of executing a set of instructions, the set of instructions including:
• determining a difference between the inside temperature and the outside temperature;
• determining a plurality of quiescent periods from the inside temperature;
• determining a rate of change during each of the plurality of quiescent periods;
• comparing the rate of change with the difference;
• and
• determining a thermal efficiency of the structure from the comparing,
• wherein the processor includes a filtering module and certain ones of the plurality of quiescent periods are eliminated using the filtering module, and wherein the processor determines a typical quiescent period for a given difference and the filtering module correlates the difference with the given difference so as to eliminate certain ones of the plurality of quiescent periods that deviate from the typical quiescent period at the given difference.