Brian,
I'm looking into a weatherizaton business opportuity here in Chicago. All the talk is that 90% of the homes that are targeted are low income, balloon framed and need air sealing , insulatoin and either a Boiler cleaning or efficiency replacement. They talk about mandating 2 part spray foam. Is this really necessary? What about Nu wool? Can I use that for exterior walls and attics, etc? Each house is tested with a Flir and Blower Door to get a Air flow CFM reading, then a work order is generated by a ROI model program. The Weatherization contractor then is supposed complete the work order (labor and materials limit of $4200) and perform their own blower door test to see if the target Air flow CFM is met... Is this business worth going after?