Types of Insulation - Basic Forms

Form Method of Installation Where Applicable Advantages
Blankets: Batts or Rolls
  • Fiber glass
  • Rock wool
Fitted between studs, joists and beams All unfinished walls, floors and ceilings Do-it-yourself.

Suited for standard stud and joist spacing, which is relatively free from obstructions.

Loose-Fill
(blown-in)
or Spray-applied
  • Rock wool
  • Fiber glass
  • Polyurethane foam
Blown into place or spray applied by special equipment Enclosed existing wall cavities or open new wall cavities;

Unfinished attic floors and hard to reach places

Commonly used insulation for retrofits (adding insulation to existing finished areas).

Good for irregularly shaped areas and around obstructions.

Rigid Insulation
  • Extruded polystyrene foam (XPS)
  • Expanded polystyrene foam (EPS or beadboard)
  • Polyurethane foam
  • Polyisocyanurate foam
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 weather-proof facing

Basement walls

Exterior walls under finishing (Some foam boards include a foil facing which will act as a vapor retarder. Please read the discussion about where to place, or not to place, a vapor retarder.)

Unvented low slope roofs.

High insulating value for relatively little thickness.

Can block thermal short circuits when installed continuously over frames or joists.

Reflective Systems
  • Foil-faced paper
  • Foil-faced polyethylene bubbles
  • Foil-faced plastic film
  • Foil-faced cardboard
Foils, films, or papers: Fitted between wood-frame studs joists, and beams Unfinished ceilings, walls, and floors Do-it-yourself.

All suitable for framing at standard spacing. Bubble-form suitable if framing is irregular or if obstructions are present.

Effectiveness depends on spacing and heat flow direction.

Loose-Fill
(poured in)
Vermiculite or Perlite
Not currently used for home insulation, but may be found in older homes