Batts, insulation material

Insulating materials and systems Blanket and batt Glass fiber, paper faced 16 0.046 ... 

R factor or value- A measure of a materials resistance to the passage of heat. New homewalls are usually insulated with 4" of batt insulation with an R value of R-13, and a ceiling insulation of R-30. 

Batt/Blanket - A flexible roll or strip of insulating material in widths suited to standard spacings of building structural members (studs and joists). They are made from glass or rock wool fibers. Blankets are continuous rolls. Batts are pre-cut to four or eight foot lengths. 

Note ( ) Adopted from the U.S. Department of Energy 1997 Insulation Fact sheet, (b) Insulation is also effective at reducing cooling bills. These levels assume that you have electric air-conditioning, (c) R-Values are for insulation only (not whole wall) and may be achieved through a combination of cavity (batt, loose fill, or spray) and rigid board materials, (d) Do not insulate crawl space walls if crawl space is wet or ventilated with outdoor air. 

Vapor Retarder - A material that retards the movement of water vapor through a building element (walls, ceilings) and prevents insulation and structural wood from becoming damp and metals from corroding. Often applied to insulation batts or separately In the form of treated papers, plastic sheets, and metallic foils. 

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