Easy Efficiency Improvements Pay Off

My family’s house in Newton, Massachusetts, is a standard family home, but by making incremental improvements in air sealing, insulation, and lighting—and with the help of a whole-house electricity monitor—we have been able to reduce energy consumption more than 50%. A $1,175 investment is saving us about $1,000 per year in energy costs, and has made our home much warmer and more comfortable.

Last May, Flemming Lund of Infrared Diagnostics in Sudbury, Massachusetts, performed an energy audit for us. The results weren’t entirely surprising; I didn’t expect our aging suburban home to be completely leak-free and perfectly insulated. Nonetheless, the energy audit was extremely useful in pointing out several high return-on-investment steps that we could take to increase our home’s energy efficiency.

But the audit was just a stepping stone; the next step was vital: I got down to it. I installed blown-in cellulose insulation in areas where it was deficient, sealed cracks and gaps, replaced old weather-stripping, and then had a follow-up audit to assess progress.

The photos are from the two audits, and show just how much of a difference the work had made. Although Flemming calibrated the infrared camera to account for temperature differences between the two audits, the outside temperature during the first audit was 50°F and 38°F during the second. The before-and-after results are pretty evident, nevertheless.

Loose-fill insulation was all installed by hired contractors, as was much of the air-sealing work. However, I made many of the most significant improvements myself—looking back over the initial audit report, I simply retraced the steps on a cold day, found air leaks by hand (literally) and sealed them with a caulking gun.

Although the follow-up audit pointed out some problems missed during the upgrade, as well as some new ones that were overlooked during the first audit, it was confirmed that much progress had been made.

Air Sealing...

Aside from the awesome infrared images of improved insulation, perhaps the most valuable information from my follow-up audit was that these simple air-sealing measures more than halved air infiltration, from 0.87 natural air changes per hour (NACH) during the heating season to 0.42 NACH.

The benefits of my air-sealing work confirmed my long-held belief that air sealing should be the first step in improving a home’s energy efficiency. It’s cheaper and easier than an insulation upgrade, and helps prevent air from moving through insulation, losing R-value. It also shows that hiring a contractor to do the job may not be the right course—much of the benefit came from the simple things I did.

Insulation...

Once sealing is done, improving insulation can add to the benefit by helping your house retain heat.

After insulating, we noticed that there are no more cold spots on the walls that create uncomfortable areas in the house. Our upgraded insulation and air sealing made the house more comfortable, easier to heat up in the morning when the programmable thermostat kicks on, and our utility bills much lower.

Lessons Learned...

Having taken these steps, we came to realize that there is no silver bullet: Improving the energy efficiency of our house is an ongoing process, and there is still much to be done. 

Although the follow-up audit pointed out some problems missed during the upgrade, as well as some new ones that were overlooked during the first audit, it was confirmed that much progress had been made.

Payback Time...

My gas utility, National Grid, had a rebate program that paid 75% of the cost of the air sealing and insulation, which made something of a difference. But the savings are staggering: Before improvements, we paid $168 per month ($2,016 per year) for space and water heating, and cooking. We now pay $89 per month ($1,068 per year), which means we save almost $1,000 per year as a result of our minimal investment.

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Tom Harrison was turning his thermostat down as a teenager in the first energy crisis, and comes from a family whose motto is “waste not, want not.” His blog, “Five Percent: Conserve Energy” (www.fivepercent.us), details his family’s efforts to conserve energy. He is the chief technology officer at Energy Circle.

This article was adapted from Energy Circle (www.energycircle.com), where you can learn more about residential energy saving, home insulation, and air-sealing.