An Alliance to Help Illinois Residents Lower Their Energy Costs

The Energy Assessment: What to Expect

Often, the first step in making your home more comfortable and energy efficient is to invite a home performance contractor to conduct an energy assessment. The assessment will vary depending on the contractor and your home, but here is a general idea of what to expect from the $99 assessment offered by Energy Impact Illinois’ participating contractors.

A contractor will arrive at your home at the scheduled time, either alone or with another person to help with the technical aspects of testing. Generally the contractor will start with a brief summary of what they will be doing, what areas of your home they’ll need access to, and how long everything should take. They will also ask about comfort issues and how you use your home, and give you an opportunity to ask any questions. If applicable, we encourage you to mention to the contractor that you hope to earn an Illinois Home Performance with ENERGY STAR certificate.

After this, the contractor will conduct a brief walk-through of your home to identify some general elements of energy efficiency, as well as any obvious strengths or weaknesses of your home.

Once the walk-through is complete, the contractor will conduct several diagnostic tests:

Combustion safety testing. The contractor will examine the venting and air quality of your home and ensure that your combustion appliances (water heater, furnace, boiler, gas stove, etc.) are venting exhaust appropriately. The contractor will close and latch all your windows and doors and turn on the dryer and all exhaust fans to create a worst case scenario of “negative pressure” and take measurements of air quality near combustion appliances, ensuring they are not “spilling” carbon monoxide and other gases into the living space. The results of this test can influence what kinds of improvements the contractor will recommend.

Blower door test. The contractor will conduct a blower door test to identify how much air is leaking into and out of your home. The blower door tool is installed at the main entrance of the home and all the other exterior doors and windows are securely closed. The powerful fan in the door is then turned on and begins to suck air out of the home. This process provides a measure of the total amount of air leakage. 

Infrared Camera Test. To identify where air is leaking into and out of your home, the contractor will use an infrared camera to look for hot and cold spots in exterior walls and ceilings. Identifying and correcting these problem areas is typically the biggest and most cost effective approach to improve efficiency and comfort. This test is often conducted in combination with the blower door test.

Manual Insulation Check. To determine the current levels of insulation in the home, the contractor will look into accessible attic and wall spaces to see if insulation is present and to measure the current levels.


Heating System and Water Heater Efficiency Test. A furnace may be labeled as 92% or 85% efficiency (AFUE), but that doesn’t mean it’s performing at that level. Age and/or poor maintenance can affect the performance, so the contractor will check the actual efficiency of your furnace or boiler and hot water heater.


Once the tests are complete, the contractor will use the data collected to calculate the efficiency of your home and make recommendations. Within five business days, the contractor will send you an assessment report that shows the expected cost of each recommended improvement including any rebates you qualify for and whether or not you will qualify for an Illinois Home Performance with ENERGY STAR certificate.

Recommendations typically include air sealing the trouble spots identified with the infrared camera and adding insulation where it’s currently insufficient – these are typically the least expensive and most effective long-term improvements. Other recommendations may include duct sealing and tuning up or replacing an old boiler or furnace. Window replacement is rarely recommended because the efficiency gains are low and the cost is high. Lastly, the contractor may also identify smaller do-it-yourself improvements, such as installing a programmable thermostat, low flow showerheads, and high efficiency lighting.

Once you’ve decided which improvements fit your needs and budget, you can talk with a contractor to schedule the work. The contractor should be able to answer any questions you might have, but you’re always welcome to call us for unbiased and practical information – either through your local energy advisor or our general phone line: 1-855-9-IMPACT.