When it comes to HVAC systems, you can think of your home as a kind of organism. It has walls and insulation for its skin, uses ventilation to breathe, and the conditioned air circulates through ductwork the way blood circulates through the body, returning to the furnace and air conditioner (or heart) on each cycle. And just as your health is a combination of all the systems in your body working together, the health of your energy systems depends on all of the systems in your home working together efficiently.
If your ductwork leaks, your furnace heats your home less efficiently; if you have passive solar heat gain during the summer, your insulation can work against you. That’s the concept of whole-house energy efficiency.
Focus your attention on these six areas in turn:
Air sealing. When unconditioned air is coming into your home and conditioned air is escaping, you’re losing energy. Sealing air leaksprevents air from escaping, and keeps your energy where you want it.
Duct sealing. Even inside your home, air can escape to places you don’t want it – inside crawlspaces, for example. Taking care of your ductwork means that your conditioned air will make it to your living areas.
Insulation. Even when air is kept inside, heat can escape through walls and ceilings. Insulation plays its part in your whole-house energy efficiency by slowing heat transfer into and out of your home.
Windows and doors. Weatherstripping and caulk can be used to seal cracks and leaks around windows and doors. In addition to air sealing these areas, also consider how outdoor landscaping affects their efficiency. For example, are windows getting enough sun exposure during the winter to take advantage of free solar heat?