Insulation
CSI Division 07, Thermal & Moisture Protection
Material installed within a building's walls, roof, and floor assemblies to resist heat flow, keeping conditioned indoor air from escaping and outdoor temperatures from penetrating, available in many forms (batt, rigid board, spray foam, blown-in) chosen based on the specific assembly and performance requirement.
Why it matters
Insulation performance depends heavily on correct, continuous installation, not just the material's rated R-value; gaps, compression, or missing insulation at corners and penetrations create thermal bridges that can undermine a significant portion of the assembly's intended performance, invisible once finishes cover it.
On a real project
A wall assembly is insulated with batt insulation cut and fitted carefully around every electrical box and pipe penetration, avoiding the gaps and compression that would otherwise reduce its effective performance in exactly those spots.
Who this matters most to
A Carpenter or specialty insulation installer fits insulation into wall and ceiling cavities, a task that looks simple but is easy to do sloppily in ways that aren't obvious once drywall covers it. A Sustainability/LEED Consultant may require blower-door testing or thermal imaging to verify actual installed performance on a project targeting specific energy goals.
Where this goes wrong
An insulation crew installs batt insulation quickly, leaving small gaps and compressed sections around electrical boxes and wall corners rather than carefully fitting each piece. The wall is covered with drywall before anyone catches the gaps, and the building's actual energy performance falls noticeably short of what the design calculated, discovered only after occupancy through higher-than-expected utility bills.