All-Electric or Dual-Fuel Heating
Space heating is all-electric or dual-fuel/hybrid. (At Platinum, all-electric only.)
Spec
Applies uniformly from Gold upward.
Scope
The primary space-heating system — central heat pump, ducted air handler, mini-split, or hydronic system.
Requirements
- 01.
At Gold: space heating must be either (a) all-electric (heat pump preferred, resistance backup OK) or (b) a dual-fuel hybrid system (heat pump primary, gas backup for extreme cold).
- 02.
At Platinum: all-electric only. Dual-fuel is not accepted.
- 03.
Heat-pump capacity must be sized to meet 100% of the heating load at the local 99% winter design temperature (per Manual J), or a supplementary heat source must cover the gap.
Documentation
Evidence the inspector / Institute will need.
- 01.
Equipment spec sheet for installed heat pump showing HSPF2 (≥ 8.1 for ENERGY STAR cold-climate, ≥ 8.5 for cold-climate ENERGY STAR Most Efficient).
- 02.
Manual J load calculation showing the heating load at design temperature and the equipment capacity at that temperature.
- 03.
For dual-fuel systems: thermostat configuration documentation showing the changeover temperature (typically 20-35°F).
Guidance
Cold-climate heat pump selection
Modern variable-speed heat pumps maintain 100% of nameplate capacity down to 5°F and 75%+ down to -15°F — well past where dual-fuel systems used to be necessary. NEEP's Cold-Climate Heat Pump list filters for systems that maintain capacity at low temperatures. ENERGY STAR Cold Climate label is the easiest filter.
Resources
- NEEP Cold Climate Air-Source Heat Pump List →
Searchable database with low-temperature performance data.
- ENERGY STAR Heat Pumps →
Includes Cold Climate certified list for HSPF2 ≥ 8.1.
Note
IRA federal tax credit covers 30% of installed cost up to $2,000 for qualifying HPs. Many states stack additional rebates of $1,000-$8,000 through utility programs.