Dear UMH community, I have modeled two nominally identical buildings, one in Atlanta, Ga, the other in Pittsburgh, PA. While the wall & roof constructions differ, using the ASHRAE 90.1 definitions for the respective climate zone, the floor constructions:
- are identical for the heated floor portion (about 20% of the total floor)
- are identical for the unheated portion of the floor
- there is NO underfloor insulation (the heated slab is in contact with the earth below)
My results for Atlanta show substantial energy savings (~35%) compared to an ASHRAE baseline. Results for Pittsburgh, however, show only 6% energy savings. All of the difference is in gas usage for the hot water boiler.
That makes no sense to me. Can you make any suggestions regarding what to look at in order to understand the discrepancy? Thanks so much!
p.s., the IDFs have been extensively compared and I'm confident they're identical except for wall and roof constructions.
