IECC CZ 3A: Atlanta, Dallas, Charlotte, Raleigh, Memphis area. HDD: 3000-4000. CDD: 2000-3500. Design temps: summer 92F/74F wb, winter 17-22F. Residential envelope: ceiling R-38, wall R-20 or R-13+5ci, floor R-19, slab R-0. Windows: U-0.30/SHGC-0.25. Air leakage: 3 ACH50. Heating: heat pumps increasingly common (efficient in moderate winters). Cooling: significant load, SEER 15+ recommended. Moisture: warm-humid = vapor drive inward in summer. Wall assembly: no vapor barrier on interior (Class III or none). HVAC: proper dehumidification important (supplemental dehumidifier or variable-speed equipment). Termites: high to very high probability. Seismic: SDC B-C depending on soil.