If you have an existing home and want to reduce your energy bills, here are eight ways to do that. They are simple and basic because that’s what energy saving is – simple and basic. If you read the latest Green Building guidelines published by the National Association of Home Builders (NAHB), you will find that building an energy-efficient home is a very big part of getting a Green Building rating. However, if you look closely at what is required for an energy-efficient home, with the exception of just a few new ideas, it is the same attention to detail that has always been at the heart of optimum energy efficiency: minimize infiltration and conduction losses.
Infiltration losses are air leaks, the direct loss of heat (or air conditioning) due to a “loose,” or drafty, house.
Conduction losses are direct energy losses through the walls, floors and ceiling/roof. Here, insulation makes a difference. Just as you are warmer with your winter coat on, your house will need less energy to heat or cool it if there is more insulation in the envelope (i.e., walls, floor, ceiling) and the windows are energy-efficient (double-glazed or better).
In new construction, there are some new materials being used to decrease energy use even further. Structural insulated panel systems (SIPS) and insulated concrete foundation systems (ICFS) are becoming more popular among green-oriented and energy-conscious builders. Even though these are somewhat “high tech” and “leading edge” products, what they accomplish remains the same: they reduce infiltration and conduction losses.
Another point made by the NAHB Green Building guidelines is that your new home should be smaller! The average size single-family home in the United States has grown by more than 50 percent in the last 20 years. Energy consumption is directly proportional to the size of the home.
The one other area that deserves attention is the efficiency of the heating and/or cooling unit you are using. Again, the goal is simple: use the least amount of energy to produce the desired heating or cooling.
As they say, it’s not rocket science!
So, here are eight things you can do, right now, in your existing home. For reference, we are assuming your home is less than 50 years old. If it’s older than that, optimum energy efficiency may not be practical or in the best interest of your home.
- Check your attic. If you don’t have the equivalent of at least 8-10 inches of fiberglass insulation, add more until you do.
- Check your cooling equipment. If it’s more than 10 years old, replacing it will, most likely, be cost-effective with a relatively quick payback. And be sure to get the maximum energy rating. This is one area when waiting for the old equipment to die does not make economic sense.
- Install foam “draft enders” on all outlets and switches in exterior walls.
- Keep all of your windows tightly closed when using air conditioning (A/C) or heat.
- If you don’t have good-quality double-glazed windows, consider upgrading. If you do upgrade your windows, we recommend replacement of the entire unit by a qualified window specialist. This will be more expensive and disruptive but will produce much more satisfactory results.
- Check the weather-stripping on all doors. If it’s marginal, replace it.
- Check your heating equipment. If the combustion efficiency isn’t at least 85% for oil and 90% for natural gas, replace or repair the equipment. This is one place where a 5% increase in efficiency will result in an almost direct 5% savings in energy.
- Turn your thermostat down (or up, if A/C). If your house is unoccupied a lot, consider a programmable thermostat. Only heat how much and when you need it.
An energy-efficient home is a well managed home. Be conscious about how you use (or lose) energy. Think simple: infiltration (air leaks), conduction (through the walls, windows, floor, and ceiling) and equipment efficiency. Good maintenance and attention to detail make all the difference.
Finally, think balance. A tight home may encourage indoor air quality (IAQ) problems. Good ventilation (outside the insulation line) is important to a healthy home. Also, mechanical ventilation to bring some fresh air into the living area is vital. Remember, the most efficient home has the following qualities:
- A cube shape (to minimize wall and roof surface for a given floor area),
- No windows,
- Only one door, and
- No interior ventilation.
Such a home would use less than half the energy of a typical home built in the 20th century. However, you would not (or could not) live in it. Optimum energy efficiency is about BALANCE between heat loss (or gain) and livability.
For 90 percent of the homes in the United States, attention to this list will result in a 10 percent or better improvement in energy consumption. Considering that there are more than 100 million homes in this country, a 10 percent energy savings is HUGE! And it’s not hard.