From heat pumps to lightbulbs, the home provides multiple opportunities to improve efficiency, save money on utility bills, and reduce personal carbon emissions. Three stand out. But unless you are a skilled carpenter, you may want to engage a reliable contractor.

First, though, get a home energy audit and rating. They measure how efficiently systems are working in the home and will identify where energy is being wasted.

Insulation: There’s a good chance the audit will find that your house could use more insulation. There are various types, each having a specific purpose. The latest technology is spray foam, which comes in two types, open cell and closed cell. Closed cell has the better R-value, and the best R-value of all insulation per inch. (“R” stands for resistance to heat flow; the higher number, the more effective the insulation.)  Spray-foam insulation seals the house, provides sound deadening, and stiffens walls; closed-cell insulation is also a moisture barrier. The main drawback is cost: two to three times as much as fiberglass insulation. But spray foam lasts two to three times longer, with a life expectancy of 80 years. Unlike other insulation, spray foam does not lose R-value over time. And its cost savings can approach 40 percent, so it should eventually pay for itself and more.

Note: Do not use spray foam that’s formed using hydrofluorocarbons (HFCs), which severely damage earth’s ozone layer. These were to be phased out as of January 2021, but may still be in a contractor’s inventory. Instead make sure your spray foam uses a hydrofluoroolefin (HFO), which tend to be nontoxic, nonflammable, and do not react with ozone.  

Windows: Like gains for other energy-efficiency measures, those from upgrading windows depends on where you start. If your windows are wood-frame, rattle in dry weather, and single pane, new double-pane windows will increase comfort, reduce outside noise, improve ease of use, and possibly increase the resale value of the home.

Windows are rated using five performance categories. The U-Factor measures the rate of heat transfer and defines the insulative quality of the window. The lower the U-Factor, the better the window. The Solar Heat Gain Coefficient (SHGC) measures how well the window blocks heat caused by sunlight on a scale from 0 – 1, with windows having a typical value from 0.25 to 0.8 and the lower the number the better. Air Leakage or AL measures the amount of air that leaks through the joints of the window, noted in cubic feet of air through one square foot of window area. The lower the AL, the better the window. Most industry standards and building codes require a maximum AL of 0.3 per minute. Then there is Visible Transmittance or VT, which measures the amount of light the window passes. Like SHGC it is measured on a scale from 0 to 1, with values ranging from 0.2 to 0.8, with the higher the VT the better. The final category is Condensation Resistance. This measures how well the window resists water build- up, on a scale from 0 to 100, with the higher the number the better. Homeowners replacing single-pane windows with ENERGY STAR windows will probably see the biggest benefits, but new windows have such high return on investment it may be worth doing even if your windows are older than, say, 25 years.

Appliances: This is a big subject. Suffice it to say that any new ENERGY STAR appliance will reduce your electricity draw from older refrigerator, dishwasher, clothes washer, clothes dryer, or electric hot-water heater by at least 20 to 30 percent and probably more. ENERGY STAR washing machines will use substantially less water for the same or better results. To put things in perspective, if all clothes dryers bought in the US were ENERGY STAR certified, the Americans economy would spend $1.5 billion less a year on electricity and save carbon emissions equivalent to more than two million vehicles. 

Hot Weather: Even in the Northeast, air conditioning can be a big expense in heat waves. With global warming unabated, this expense will rise. Instead of more air conditioning, consider a whole-house dehumidifier. Humidity magnifies the heat you feel by reducing the effects of your natural cooling system, evaporation moisture on your. Since they do not cool the air, dehumidifiers need a lot less energy. Stand-alone units are helpful for a room, but whole-house systems are worth a look. And drink plenty of water.

If you decide to undertake any of these projects, be sure to check for incentives, rebates, tax breaks, and other money-saving programs available for energy-saving efforts. You’re likely to find some.

Additional reading:

Spray-foam insulation is superior to fiberglass largely because it’s denser and expands into all the cracks and holes when properly applied.