Alternative HVAC systems. Traditional gas or electric furnaces, especially units that are Energy Star rated, perform well, but increasingly new technologies are being introduced that offer higher levels of comfort and efficiency. Air sourced heat pumps, and geothermal heat pumps are becoming more common in the market and most utility programs now offer loans or cash rebates for installing them.
Likewise, evaporative coolers that are Energy Star rated can be ideal in warmer climates, and with proper windows can match the comfort level of less-efficient electric units. Biomass stoves may also be appropriate for heating homes or water in remote areas where natural gas is unavailable. Biomass stoves use wood pellets, corn or other organic materials as fuel, are highly efficient, and consume renewable resources. Finally, on demand hot water heaters, especially in the master bath, can add significant comfort while reducing water and energy waste. For remodelers installing soaking tubs, highlighting the benefits of a small on demand water heater is an easy sell because the units capitalize on short runs, endless hot water and energy efficiency.
Duct sealing/air tightening. A poorly sealed duct system can render even highly efficient heating and cooling systems wasteful. The quality of the duct work can ultimately determine the efficiency of the heating and cooling system, but poorly sealed ducts pose other threats besides wasted energy and money. Ducts that are leaky, or not properly sealed, pose several serious risks to the home's occupants. First, holes or poorly sealed joints in the duct system force conditioned (heated or cooled) air into places it should not be. Crawlspaces, walls and attics can become over pressurized when if leaky supply ducts run through them which forces conditioned air through the building envelope and outside of the home.
Likewise, if the return ducts are not properly sealed they will suck in air from these same spaces. This can create indoor air quality issues by introducing dust, mold spores, and other allergens that are pulled from unconditioned spaces. Another concern with leaky ducts is if the gas powered heating equipment is not properly vented. Leaky supply ducts can pull in harmful carbon monoxide and distribute the gas throughout the home. Finally, poorly sealed duct systems can significantly reduce the comfort of the home. Inconsistent duct work will leave some areas of the home perpetually too hot or too cold, and create and imbalance in air pressure from one room to another.
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