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Part 2

Part 1, the writer’s initial experience with CEDA (Community and Economic Development Association of Cook County, Incorporated), ran in the Nov. 11, 2009, issue of the RoundTable. The following is the continuation of that article on CEDA home weatherization.

Health and Safety Items

The CEDA contractor visited the site on Nov. 25 to assess and plan the “Health and Safety” work. The contractor told the owner that they would install two fire extinguishers, two smoke detectors, two carbon monoxide detectors, and replace almost all incandescent light bulbs with CFL light bulbs equivalent to 60-watt incandescent bulbs. They would also replace the duct going from the dryer through the outside wall and the exhaust duct going from the second-floor bathroom through the roof. They would replace the old accordion-style flexible aluminum ducts with ones made of rigid, smooth aluminum. (The rigid aluminum ducts are safer because they do not catch and hold lint from the dryer. Lint caught in the duct is a fire hazard.) They changed the valve and the gas supply line into the water heater. The Health and Safety work was completed in two short visits.

Insulation and Sealing

On Dec. 7, the same contractor returned to make a plan for insulation and sealing against air infiltration. The work began on Dec. 9. It took three men working two 10-hour days plus a 4-hour day to do all of the sealing and insulation.

Because the first floor of the house was made of brick, the first floor walls had to be insulated via holes drilled through the wallboard on the interior of the house (see photo). They drilled 132 holes, each 2 inches in diameter. And, yes, there was a lot of dust. The contractors placed plastic sheeting over the furniture, kitchen cabinets and counters prior to the drilling, but because the house had a forced-air heating system, the dust made its way throughout the house.

The second-floor walls were insulated from the outside by drilling holes under the siding. Cellulose insulation was blown in through all of those holes. A technique called “dense packing” was used to push the cellulose into the wall spaces as tightly as possible. Then they blew in 11 inches of cellulose onto the attic floor. They glued rigid Styrofoam to the back of the hatches that opened into the attic. The knee wall behind the second-floor walls and some areas on the underside of the roof were insulated with fiberglass batts. The contractor sprayed closed cell foam from a can to seal leaks around basement windows and at plumbing penetrations into the basement. They filled the space between the top of the foundation and the brick walls with the foam. Plumbing penetrations under the kitchen sink and in the bathrooms were also sealed with foam. Weather stripping was added around three exterior doors. All of this work was completed by Dec. 14.


On Dec. 18, a CEDA inspector came to check the completed work. The contractor’s work passed this inspection. On Jan. 4, the State of Illinois Home Weatherization Assistance Program sent an inspector to make another inspection. Only 5 percent of the homes weatherized by CEDA receive the additional inspection. This inspector found a few things that the contractors would have to come back and fix. He said they did a very good job overall. The contractor returned to the site on Jan. 5 to fix the items required by the state inspector.  One contractor did all the work on the house.

The owner said she was very satisfied with the job done by CEDA. The work done on her house was valued at $5,200, the maximum allowed per house. It was done at no charge to her because she met the financial qualifications for the CEDA program. However, although the contractors filled the holes that they drilled, the owner has had to add some more wall compound, to sand and then paint the wall areas.


To find out how much the sealing and insulation will save the owner in gas usage, she did the following:

First, she went to MyAccount on to find out the gas usage in the residence over the past five years. (She had owned the house since March of 2009.)

The dollar amount of the gas bill cannot be used to calculate savings because of fluctuations in weather (degree days) and in the prices of gas. A degree day relates to how much heat (or cooling) is needed in a given climate because of average outside temperatures. A therm is a measure of the heat value in the natural gas and is used as the basis for calculations that appear on the bill.

Looking at one’s recent gas usage enables one to isolate the effect of the CEDA weatherization.

Dividing the therms by the degree days for a given billing period indicates the efficiency of the house.

During the three NICOR gas billing periods prior to CEDA weatherization, the owner used a total of 191.11 therms during a time period of 1253 degree days.

191.11 divided by 1253  =  0.1525219 therms per degree day.

During the two NICOR billing periods after her CEDA weatherization, she used 290.75 therms during 2466 degree days.

290.75 divided by 2466  =  0.1179034 therms per degree day.

0.1179034 divided by 0.1525219  =  0.773026  i.e. a 22.7 percent reduction in gas use due to CEDA weatherization.

The CEDA weatherization has reduced gas usage by 22.7 percent. This savings will continue year after year.