Types of Insulation
| Form |
Insulation materials |
Where applicable |
Installation method(s) |
Advantages |
| Blanket: batts and rolls |
Fiberglass
Mineral (rock or slag) wool
Plastic fibers
Natural fibers |
Unfinished walls, including foundation walls, and floors and ceilings. |
Fitted between studs, joists, and beams. |
Do-it-yourself.
Suited for standard stud and joist spacing, which is relatively free from obstructions. |
| Concrete block insulation |
Foam beads or liquid foam:
Vermiculite or perlite pellets |
Unfinished walls, including foundation walls, for new construction or major renovations. |
Involves masonry skills. |
Autoclaved aerated concrete and autoclaved cellular concrete masonry units have 10 times the insulating value of conventional concrete. |
| Foam board or rigid foam |
Polystyrene
Polyisocyanurate or polyiso
Polyurethane |
Unfinished walls, including foundation walls;
floors and ceilings;
unvented low-slope roofs. |
Interior applications: must be covered with 1/2-inch gypsum board or other building-code approved material for fire safety.
Exterior applications: must be covered with weatherproof facing. |
High insulating value for relatively little thickness.
Can block thermal short circuits when installed continuously over frames or joists. |
| Insulating concrete forms (ICFs) |
Foam boards or foam blocks |
Unfinished walls, including foundation walls, for new construction. |
Installed as part of the building structure. |
Insulation is literally built into the home's walls, creating high thermal resistance. |
| Loose-fill |
Cellulose
Fiberglass
Mineral (rock or slag) wool |
Enclosed existing wall or open new wall cavities;
unfinished attic floors;
hard-to-reach places. |
Blown into place using special equipment; sometimes poured in. |
Good for adding insulation to existing finished areas, irregularly shaped areas, and around obstructions. |
| Reflective system |
Foil-faced kraft paper, plastic film, polyethylene bubbles, or cardboard |
Unfinished walls, ceilings, and floors. |
Foils, films, or papers: fitted between wood-frame studs, joists, and beams |
Do-it-yourself.
All suitable for framing at standard spacing. Bubble-form suitable if framing is irregular or if obstructions are present.
Most effective at preventing downward heat flow; however, effectiveness depends on spacing. |
| Rigid fibrous or fiber insulation |
Fiberglass
Mineral (rock or slag) wool |
Ducts in unconditioned spaces and other places requiring insulation that can withstand high temperatures. |
HVAC contractors fabricate the insulation into ducts either at their shops or at the job sites. |
Can withstand high temperatures. |
| Sprayed foam and foamed-in-place |
Cementitious
Phenolic
Polyisocyanurate
Polyurethane |
Enclosed existing wall or open new wall cavities;
unfinished attic floors. |
Applied using small spray containers or in larger quantities as a pressure sprayed (foamed-in-place) product. |
Good for adding insulation to existing finished areas, irregularly shaped areas, and around obstructions. |
| Structural insulated panels (SIPs) |
Foam board or liquid foam insulation core
Straw core insulation |
Unfinished walls, ceilings, floors, and roofs for new construction. |
Builders connect them together to construct a house. |
SIP-built houses provide superior and uniform insulation compared to more traditional construction methods; they also take less time to build. |