The transfer of thermal energy by conduction, convection and radiation from areas of higher energy intensity, or warmer areas, to lower energy intensity, or cooler areas.

Resistant to water, non-absorptive. Fiberglass and sprayed foam insulations are typically hydrophobic, that is, they do not readily absorb and manage moisture, but rather provide possible condensing surfaces.

Readily take up and/or retain moisture. When referring to cellulose insulation, the hygroscopic properties of cellulose allow it to manage the natural humidity drives that occur in all structures, allowing assemblies to gradually transmit airborne moisture.

International Building Code

Impact Insulation Class refers to how well impact noise is transmitted through a floor system. Unlike airborne sound transmission, impact noise is primarily transmitted through the floor joists and therefore needs to be separated with resilient channel. The higher the value, the better the floor isolates the sound.

These are the open spaces or pathways that exist and interconnect in buildings between the walls and ceilings. These offer pathways for fire, heat, odor, insects and vermin to travel and remain hidden from the building occupants.

International Residential Code