Insulation
Insufficient insulation is one of the leading causes of energy waste in buildings. Proper insulation conserves energy, saves money on a building’s heating and cooling bills, and keeps building occupants comfortable. Insulation helps keep heat in during the winter, cool air in during the summer, and protects the building from moisture from condensation.
Insulation is rated by a term called “R-Value,” which is a measurement of the material’s resistance to heat flow. The higher the R-value, the better the insulation is at doing its job. Insulation can be installed in a new building as part of the building process, or added to an existing building. The type and strength of insulation used in a building depends on a number of factors such as the building’s heating system and local building codes.
A building should be insulated from top to bottom: the foundation, the floors, exterior walls, the HVAC system, and especially the attic (think of putting a hat on in the winter to keep warm – same concept).
Recommended R-Values for Colorado*
Homes with natural gas heat or heat pump: Attic R-49, Wall R-18, Floor R-25, Crawlspace R-19, Basement R-11
Homes with electric heat: Attic R-49, Wall R-22, Floor R-25, Crawlspace R-19, Basement R-19
Types of Insulation*
Form |
Type of Material |
Where to Use |
Installation Method |
|
Blanket
(batts and rolls) |
Fiberglass
Wool
Plastic fibers
Natural fibers |
Unfinished walls
(including foundation walls)
Floors
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 |
Foam beads
Liquid foam
Polystyrene
Polyisocyanurate Polyiso
Polyurethane
Vermiculite
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 Polyiso
Polyurethane |
Unfinished walls, (including foundation walls)
Floors
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 Foam blocks |
Unfinished walls (including foundation walls) 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
Wool |
Enclosed existing wall
Open new wall
Unfinished attic
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 Cardboard |
Unfinished walls Ceilings
Floors |
Fitted between wood-frame studs, joists, and beams |
Do-it-yourself
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 |
| Rigid fibrous or fiber insulation |
Fiberglass
Mineral
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
Open new wall cavities
Unfinished attic |
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
Roofs
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 |
*U.S. Department of Energy
