Quality Insulation Installation (QII) is a procedure for ensuring that thermal insulation has been properly installed and that air sealing has been properly done in a home. It is based on industry standards (NAIMA) and similar to widely recognized national standards (RESNET and Energy Star), but it also has some unique requirements. Much of QII is simply installing insulation as the manufacturers intended.
QII is triggered when, using the performance compliance approach, the energy consultant/designer takes an optional compliance “credit” for QII. Actually, it is not a credit but the removal of a penalty that is otherwise applied to a typical house. This penalty was put in place in the 2005 Energy Code after a very extensive study showed that standard industry practice was to install insulation very poorly. So poorly, in fact that the insulative properties were dramatically reduced. The study also found that the building envelope was almost never properly sealed, making the problem even worse.
In an effort to improve standard practice in the industry, the CEC developed the QII protocols. Rather than just requiring all homes to meet these requirements, the compliance modeling software takes a “guilty until proven innocent” approach and will automatically derate the insulation by as much as 13.3%, unless the user specifies QII. This then triggers the requirement for HERS verification.