Which type of insulation is the best and what is the difference between the types?

Which type of insulation is the best and what is the difference between the types?

When insulating your home, you can choose from many types of insulation. To choose the best type of insulation, you should first determine the following:

Where you want or need to install/add insulation
The recommended R-values for areas you want to insulate.

TYPE

MATERIAL

WHERE APPLICABLE

INSTALLATION METHODS

ADVANTAGES

Blanket: batts and rolls

Fiberglass

Mineral (rock or slag) wool

Plastic fibres (polyester)

Natural fibres (sheep wool)

Unfinished walls, including foundation walls

Floors and ceilings

Fitted between studs, joists, and beams.

Do-it-yourself.

Suited for standard stud and joist spacing that is relatively free from obstructions. Relatively inexpensive.

Concrete block insulation

and insulating concrete blocks

Foam board, to be placed on outside of wall (usually new construction) or inside of wall (existing homes):

Some manufacturers incorporate foam beads or air into the concrete mix to increase R-values

Unfinished walls, including foundation walls

New construction or major renovations

Walls (insulating concrete blocks)

Require specialized skills

Insulating concrete blocks are sometimes stacked without mortar (dry-stacked) and surface bonded.

Insulating cores increases wall R-value.

Insulating outside of concrete block wall places mass inside conditioned space, which can moderate indoor temperatures.

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

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 and blown-in

Cellulose

Fiberglass

Mineral (rock or slag) wool

Enclosed existing wall or open new wall cavities

Unfinished attic floors

Other 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, rafters, 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, effectiveness depends on spacing.

Rigid fibrous or fibre insulation

Fiberglass

Mineral (rock or slag) wool

Ducts in unconditioned spaces

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 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

Construction workers fit SIPs together to form walls and roof of a house.

SIP-built houses provide superior and uniform insulation compared to more traditional construction methods; they also take less time to build.


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