Core terms · definition
Material that resists heat flow, rated by R-value, installed in walls, ceilings, and floors. Opened walls are the opportunity to upgrade insulation while it is accessible.
Source: NAIMA Insulation Institute — How Insulation Works
Where this comes up
Where this term lands on a Columbus budget
The cost pages carry the current local ranges, and the guides explain what moves them. A published range becomes a project number only after someone looks at the site.