How We Increased Our Home’s Energy Efficiency By 48%

Post Update – 5/26/22: The Instant Savers Assessment Program either no longer exists or has been changed. However, the basic information in this post is still pertinent to homeowners who wish to increase the energy efficiency of their home, thus lowering their energy loss each month.

Nearly two years ago, I scheduled an energy audit with my utility company, Ameren Illinois. I was actually inspired to do so because I was preparing for an interview with the Citizens Utility Board.  Since I was disseminating advice on reducing utility bills, I thought this would be the perfect opportunity to schedule an energy audit of my home.

Our family qualified for a free audit and energy assistance through Ameren Illinois’ Instant Savers Assessment Program, aimed at helping low and moderate income families increase the energy efficiency of their homes. Here’s a look at the chart from the Ameren website.

Number of Persons in Household
Maximum Income

The application process was very easy. Our income was verified and within 24 hours and we received an e-mail, stating that we qualified for the program.

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The ball got rolling quickly, with a follow-up phone call from Ameren Illinois, my utility company. An energy specialist was slated to arrive at my home within the week.

Our auditor, Travis, arrived promptly at 9am. What a great, informative, helpful guy! He explained the process to me and it quickly became clear why it takes an average of three hours to complete an audit.

They are thorough! This was far more extensive than any home inspection I have been through to either buy or sell a home!

We immediately discovered three problems!

A bright yellow handheld device with a thin, flexible metal rod protruding from the top was slowly waved over the surface of all items, which used natural gas. This combustible gas detector emitted a beep, which increased in intensity and volume in the presence of natural gas in the surrounding air.

The reading it takes, known as the L.E.L. – Lower Explosive Limit, is actually able to detect finite levels of gas leakage. Apparently around fifty percent of homes which are tested have some amount of gas leaking, yet the homeowners know nothing about it.

We turned out to be one of the fifty percent – twice over!

There was a leak right where you see the snakelike projection in the above photo.

In a scary turn of events, the beeping machine also found that the gas shut off valve for our dryer was leaking.

In a final blow, Travis noticed that the hot water heater exhaust pipe had been improperly installed. The problem is that improper alignment can allow the gravity-fed exhaust from the water heater to escape into the room, creating a build up of carbon monoxide.

This was not something to be ignored. The gas was turned off at the street as we awaited a rescue team to arrive to fix all three problems.

First, an Ameren journeyman replaced the leaky valve in the front of the house with lightening quick speed. Then, the inspection was put on “hold” for an additional sixty minutes, while a local contractor came out to repair both the leak in the dryer line and the hot water heater exhaust pipe.

The shiny, new water heater exhaust pipe was tested for backdrafting with a puff of artificial smoke.Everything was now in proper working order!

All problem areas rectified, we were back on track and once again testing my home’s energy efficiency.

More common problems unearthed

I learned a lot as the process turned up more areas of concern. Travis was incredibly gracious and kept up a nice stream of conversation, orally downloading facts, figures, and information as I plied him with questions.

Clogged Central Air Cage

The vents for our central air were completely clogged. Apparently, you can direct a spray of water from a hose through them and easily clean out the organic material – in our case, mostly seeds from local, prolific, cottonwood trees.

The big problem with this condition is that the coating of grime causes additional load on the AC unit. The motor must work harder to move air, shortening the length of its life and raising our utility bills.

To fix the situation, we would need to direct a gentle stream of water between the top and side of the unit, spraying outward to remove the debris and clean out the dust, dirt, and debris. This, same procedure should be followed every spring, before turning on the central air unit.

Dirty dryer vent exhaust 

Most homeowners, me included, don’t think to periodically examine the state of their dryer exhaust. We should! Dryer vent fires are quite common, but the possibility can be drastically diminished when the entire vent is vacuumed out once or twice year.

The Building Flow Leakage Test!

The final part of the inspection was something called a building flow leakage test. My front door was covered by a bright, red canopy with a large fan in the bottom, center quadrant.

As I gazed at the contraption, my mind raced back to the hazmat scene from the 1980’s movie, “ET”. This really did look eerily similar.

I watched, as numbers on the electronic readout continued to climb, telling the tale of just exactly how quickly air was flowing through my house, even with every door and window closed!

Our blower door test revealed a final number of 11.0 ACH50. The average home measures about a 10 ACH 50. However, one must compare this number with that of new construction: a 4.0 ACH 50.

So, what did all these figures mean to the homeowner?

Travis quickly broke it down to layman’s terms. My score was significant, because any level between 10 and 15 actually represents a fairly noticeable leakage problem. Primarily, and not surprisingly, problem points were areas which provide a natural bridge between the outdoor and indoor air.

Our main problem areas included:  

  • Our centralized, whole-house fan
  • Our bathroom exhaust fan
  • Our jalousie-windowed back door
  • A gap in the top plates of our interior walls (where they met the roofline)

The Improvements

Before leaving, Travis installed a number of power-saving devices in my home for free as a part of Ameren’s Instant Savers Assessment Program!

These included: 

  • A Nest thermostat . This smart, programmable thermostat works with Alexa or connects with my personal computer or phone, allowing me to control the temperature – even when I’m not at home.
  • Two smart power strips (to help reduce vampire power)
  • New low-flow faucet aerators (To reduce water use and reduce strain on the water heater)
  • New LED lightbulbs (To reduce energy usage)

As the process concluded, Travis, once again reviewed the problem areas in the house and ensured that I now understood how gaps were allowing a continuous exchange of air from indoors to outdoors.

My house was far leakier than I had ever anticipated! He left, assuring me that everything could be fixed.

We did, however, have a small financial commitment to make to the process. As homeowners, we had three minor problems, which would need to be brought up to code before project completion. The repairs would cost us less than $300.

In the meantime, a second, and even more thorough examination, would be performed by Todd Abercrombie of EverGreen Home Energy Consultants. Todd would then provide us a with a list of detailed, prioritized, actionable steps and connect us with one of Ameren’s trusted, locally-owned program allies.

The next step in the process

Once again, I didn’t have to wait long. I received a call from Todd within a week. Arriving at the agreed upon hour, he, first, repeated Travis’ initial tests, to ensure that the calculations were correct.

In addition to verifying the original energy loss numbers, a thermal imaging camera was used, to aid in defining the exact amount of heat loss, The device was aimed at doors, windows, near the ceiling, at the roofline, through the whole house fan, and, finally, up the bathroom exhaust.

This was pretty cool technology! However, it was a little alarming to see heat radiating through unseen holes in my home.

Todd explained that even brand new constructions contain some air flow. Although the numbers looked pretty high to me, Todd said that he had seen worse and reiterated Travis’ assertion that just a few upgrades could provide me with a significant reduction in heat or cooling loss. 

The next week I received an extensive, final, detailed report with a prioritized list of both necessary and suggested projects. Todd also recommended and connected us with Central Illinois Insulation, an Ameren energy program ally. 

The Final Improvements are Installed

The crew from Central Illinois Insulation were absolutely remarkable! Being in an attic on a blazing Central Illinois summer day brings about visions worthy of inclusion in Dante’s famous Inferno. But, they labored tirelessly and cheerfully, putting forth their best effort in less than ideal working conditions. 

Replacing the Bathroom Exhaust Fan

The new Panasonic Whisper Green Bath Exhaust Fan is vented properly and “hums”, rather than rattles when in use. It keeps moisture at bay even when a teenage boy is standing under running water in the shower, singing through multiple verses of his favorite songs. I was very impressed with how effectively the new fan wicked steam from the room.

Sealing the Backdoor

This was a little tricky. We really didn’t want a replacement door. I like being able to look from the backdoor into the garage. But, the original jalousie windows were like a leaky sieve. Tim Wagenbach, owner of Central Illinois Insulation, took on this task personally. He found a piece of plexiglass and had it cut to the perfect size. Then, he custom fitted it over the top of the existing window frame. It was the perfect solution!

Sealing cracks in the attic and adding insulation

Prior to the improvements, my attic only contained maybe six inches of very old, squished insulation. It’s no wonder the attic and roof were the main sources of heating and cooling loss for my home! They were the spaces, which allowed for the greatest degree of conductivity between the interior and exterior spaces.

Sealing, in the form of foam, caulk, or solid materials were applied to areas like the chimney base, top plates, wiring penetrations, plumbing penetrations, the kitchen soffit, and the whole house fan.

We had one additional request for the attic project, a plywood walkway so that the whole house fan could easily be reached for yearly maintenance. We opted to pay out-of-pocket to have the workmen to do this for us.

After that, insulation was blown in to a factor of R-49.

Adding a whole house fan cover

The final area of concern was our whole house fan. Unlike many people, we actually use our whole house fan, especially in the spring and fall, when nighttime temperatures drop and the humidity is also low. So, plugging it up permanently was not an option.

Instead, an insulated, magnetized specialty cover proved to be the perfect solution. The interior of the cover is insulated, providing an additional R-factor. Yet, the durable cover is also easy enough for my older boys to grab the magnetized corner to remove it when we are planning to use the fan.

The cost of the project 

The cost of these home improvements was nearly $4000 and was completely covered by Ameren’s Energy Efficiency Home Audit program!

Our only out-of-pocket cost was that of paying to have three minor items replaced and brought up to code and the cost of laying the plywood flooring in the attic. It was less than $500. 

A 48% Improvement!

The final report showed an amazing 48% increase in air efficiency! 

While our initial blower door test CFM level had been 11.0, the post-improvement test revealed a new number of 5.8! New construction is built to a code of 4.0.

That means our home’s level of air efficiency is now very close to that of a new build!  The results were even better than Ameren’s initial projections! Everyone was well-pleased, deeming the project a rousing success!

Does this mean my utility bills dropped by half? 

No. It’s a measure of the reduction of the overall air leakage of my home. It is one of the metrics used to determine how air moves through a structure, which affects its ability to effectively and efficiently heat and cool. 

Have I noticed a difference?

Yes, I have! 

  • Our central air, which seemed to be running constantly during the summer, began taking long “breathers” before turning on, rather than continuously cycling. This is happening even though the weather has remained hot and sticky. 
  • I can stand in the hallway and no longer feel the heat of the attic radiating through the closed whole house fan. 
  • Since the improvements, our utility bill, which commonly soared to over $200 in mid-summer and mid-winter, has never reached $200 in even one month. 

Do I recommend the program?

Absolutely! If you live in Ameren Illinois’ service area, check the on-line chart to see if you qualify for the program. Every single person involved in the process was incredibly polite, giving their time and knowledge and treating us with the utmost respect.

Special thanks to: 

  • Suzanne at the Ameren home office, who answered my initial phone call and processed our application with lightening fast speed. 
  • Travis Crocker, of Walker-Miller Energy Services, who completed our initial assessment.
  • Todd Abercrombie, owner of EverGreen Home Energy Consultants, who did a thorough, top-notch job, coming up with such a detailed, thoroughly thought through action plan
  • Tim Wagenbach, owner of Central Illinois Insulation and his amazing crew, who worked for hours without complaint in my sweltering hot attic to install the new insulation and complete the rest of the project upgrades. 
  • Ameren Illinois, who offer great service to the customers in their service area. 

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7 thoughts on “How We Increased Our Home’s Energy Efficiency By 48%”

  1. Lowering the thermostat 1 degree to 64 degrees could cause you to get pneumonia. You can end up in the hospital paying copayments not saving any money. Put your heat on 66 degrees to prevent illness. Also using a kerosene heater could cause a fire in your home and may increase your chances of getting lung cancer.

    • Christine, Thank you so much for your concern for my family. I truly appreciate it. I have done some research, however, and cooler temperatures for sleeping are recommended. Suggested nighttime thermostat settings vary from 60-62 degrees. I found no mention of pneumonia in my research.

    • Pneumonia in 64F? That seems a bit unlikely unless you have a seriously compromised immune system. I don’t think I have ever routinely kept my home at 66! I did get pneumonia once about 25 years ago. The World Health Organization recommends homes be kept at a minimum of 18 Celsius or 64.4 Fahrenheit. Personally I find much warmer than 64 to be uncomfortable for sleeping, I would prefer to be in a warm bed with nice thick pajamas in a cool room versus have my room be very toasty.

  2. I loved reading the nice things you say about the people who helped you with this process. I used to work in customer service and there is nothing better than an happy customer 🙂
    Awesome program by the way. It makes me wonder where are the leaks in my flat!

    • Thank you, Nathalie. We were so thrilled to be approved to be a part of this program. It was a wonderful experience from start to finish.

  3. The way you soak of these companies make me wish I lived there! I live in hot, muggy Florida, however, so I was wondering if you might write about how to cool the house this summer? I see other articles and am really interested! Thanks so much, BTW you’re a talented writer!

    • Lisa, it’s hard to make comparisons across the board, since much depends on house construction and where you live. Illinois is very humid in the summer. Our house is solid brick. So, it stays relatively cool for hours after we turn the AC off. One summer, for several weeks, (to try to save money) we turned the AC off from about 8am-3pm every day and just hung out in the basement. It stayed pretty cool and still relatively low in humidity. However, in our old home – built in 1930 – we could never have done that. Before turning the AC off for any length of time you need to monitor the relative humidity. Once it gets above 55% mold can grow. The problem with finished basements in Illinois is that you are pretty much forced to run the AC when the humidity sets in – otherwise you are fighting mold in pretty short order.


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