I have a question which might have been proposed to the Bldg. Sim. in the past but I'm not sure. Regarding underfloor air systems, since DOE2 assumes a well mixed space and cannot model the destratification effect and since the supply air temperature for heating and cooling tends to be much lower/higher than typical conditions, the throttling range tends to be quite high. There is an exception in ASHRAE 90.1 Appendix G that if you have a high throttling range you can try to argue an exception to this but I'm not sure if LEED would accept this. This might be similar to the natural ventilation issue. Would an underfloor air system which has typically 62 F to 64 F SAT with room thermostat settings of 72 to 75 F fall under this exception for LEED since DOE2 cannot mode the distratification effect or do most people try to force the throttling range down to meet LEED/ASHRAE requirements which is what I have done in the past. I did not see anything in the USGBC Credit Interpretation Rulings regarding this subject. I have heard the next version of eQuest should be able to model underfloor air systems and that Energy Plus does but until then.....

Thank you,

Ren?e Azerbegi, CEM, LEED-AP