Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.
Roof insulation grades.
The r value per inch for different types of insulation varies depending on the.
While there are additional considerations such as venting and moisture problems to take into account when you insulate under floors the united states department of energy recommends an r 25 rating in cold climates and an r 11 in warmer parts of the country.
Extruded polystyrene xps easily recognized by its blue green or pink color.
Used most in walls or below grade applications.
Up to 2 missing insulation.
Find your zone on the map and then use the chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces.
Insulation level are specified by r value.
The higher the r value the better the thermal performance of the insulation.
R value is a measure of insulation s ability to resist heat traveling through it.
Occasional very small gaps are acceptable in another place the standards say if the exterior sheathing is visible from the building interior through gaps in the cavity insulation material it is not considered a grade i installation grade ii.
Between 2 and 5 missing insulation.
For a 1 in thick 4 8 panel.
Falls in the middle of the three types of rigid foam insulation in both cost and r value.
The table below shows what levels of insulation are cost effective for different climates and locations in the home.
Type iii faced with a perlite insulation board on one major surface of the core foam and an organic inorganic asphalt.