R Rating Insulation In Attic

In particularly cold climates you might go up to r 60.

R rating insulation in attic.

Depending on where you live and the part of your home you re insulating walls crawlspace attic etc you ll need a different r value. Add insulation to attic. Insulation levels are specified by r value. Let s say the insulation you ve selected has an r value of three per inch and.

R value is a measure of insulation s ability to resist heat flow. Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation. Recommended insulation levels for retrofitting existing wood framed buildings. Inspecting your attic insulation.

See the department of energy s doe ranges for recommended levels of insulation below. As a benchmark one inch of solid wood has an r value of 1. The r value for cellulose insulation in an attic depends on several factors including the size shape and construction of your attic typical weather conditions where you live any air leaks and. While some ceilings in the southwestern part of the united states require a minimum of r 19 insulation most attics or ceiling areas require a minimum of r 38 in the ceiling.

In comparison an inch of blown fiberglass insulation has an r value of 3 1 3 4 and an inch of blown cellulose in an attic has an r value of 3 2 3 7. Your attic should have a certain amount of insulation in it and the recommended level of insulation for your attic is dependent on where you live. Typical recommendations for exterior walls are r 13 to r 23 while r 30 r 38 and r 49 are common for ceilings and attic spaces. R value is a measurement of thermal resistance and measures the ability of heat to transfer from one side of an object to another.

In general an attic s r value should be between r 30 and r 49. Houses in a cold climate should have a minimum of r 49 in the attic which is equivalent to approximately 16 of fiberglass insulation. R value insulation chart 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. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type.

First things first you need to go up into your attic inspect the condition of the insulation and calculate the current level of insulation.