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Just to keep this thread alive, I went back to see what else I could find. Using E+ and the ZoneComponentLoadSummary, I found that approximately 40% + of the Estimated Cooling Peak Load is being countered by a massive Ground Contact Floor load (Sensible-Delayed.) I was using the default ground temperatures in Energy+ (18 degC). Changing using the Building average indoor temp - 2 deg C still resulted in very high negative loads typically not associated with a sizing calculation for cooling. Finally, the slab processor measure (link below) cut the load in half. See examples below.

For me this is still quite high (at ~ 24% negative load,) but short of jumping all in...?

With 18 deg C
For example (Classroom with 1 exterior wall),
The Ground Contact Floor load is (-7,555 W.)
The Grand Total Load is (28,353 W.)

With Slab Processor measure (SurfaceProperty:OtherSideCoefficients) links below
Same classroom:
The Ground Contact Floor Load is stistrong textll (-5,255 W)
The Grand Total Load is (36,446 W)
After a while of toying with the model to max out the cooling load, the ventilation would not show up any longer on this report, so I just used the same number from previous reporting for comparison.

Just to keep this thread alive, I went back to see what else I could find. Using E+ and the ZoneComponentLoadSummary, I found that approximately 40% + of the Estimated Cooling Peak Load is being countered by a massive Ground Contact Floor load (Sensible-Delayed.) I was using the default ground temperatures in Energy+ (18 degC). Changing using the Building average indoor temp - 2 deg C still resulted in very high negative loads typically not associated with a sizing calculation for cooling. Finally, the slab processor measure (link below) cut the load in half. See examples below.

For me this is still quite high (at ~ 24% negative load,) but short of jumping all in...?

With 18 deg C
For example (Classroom with 1 exterior wall),
The Ground Contact Floor load is (-7,555 W.)
The Grand Total Load is (28,353 W.)

With Slab Processor measure (SurfaceProperty:OtherSideCoefficients) links below
Same classroom:
The Ground Contact Floor Load is stistrong textll still (-5,255 W)
The Grand Total Load is (36,446 W)
After a while of toying with the model to max out the cooling load, the ventilation would not show up any longer on this report, so I just used the same number from previous reporting for comparison.