This paper summarizes a method for testing model calibration procedures. We call this a pure test method because it tests only the calibration procedure and not the correctness of the associated simulation program. This is accomplished by using the simulation program (used with a calibration method) to generate synthetic/surrogate building energy use data for a pre and post retrofit test case. Thus the “correct” inputs are precisely known and the calibration technique can be tested for closure on the correct pre-retrofit model input values and the post retrofit energy savings along with the usual “goodness of fit” criterion.