Most manufacturers produce an r 13 batt that fits into a 2 by 4.
R13 attic insulation.
R value is a measure of insulation s ability to resist heat traveling through it.
For pricing and availability.
However the r value of insulation also depends on proper installation to avoid compressing it.
Johns manville r 13 40 sq ft single faced fiberglass roll insulation with sound barrier 15 in w x 32 ft l item 31116.
Owens corning ecotouch r 15 30 sq ft single faced fiberglass roll insulation 15 in w x 24 ft l item 821444.
The label on insulation gives its r value.
Thermal values range from a low of r 4 to a high of r 45.
The higher the r value the better the thermal performance of the insulation.
Standard fiberglass insulation batts or blankets provide an r value of 2 2 to 3 8 per inch of thickness.
Insulation level are specified by r value.
Owens corning r 13 ecotouch pink kraft faced insulation fiberglass insulation batt 16 in.
Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.
Higher numbers indicate insulation that is more effective.
The table below shows what levels of insulation are cost effective for different climates and locations in the home.