Exterior Insulation R Value

R value is a measure of insulation s ability to resist heat traveling through it.

Exterior insulation r value.

Insulation ratings are measured in r values per inch of thickness. For example a wall with 3 fiberglass batting r value of 10 8 11 9 may have an overall r value of nearly 14 because of siding sheathing and drywall. Let me explain when the general public hears an r 13 wall insulation they believe that in fact they have an r 13 insulation value in their exterior walls. R value actually stands for resistive value.

The r 0 87 value for the first value in this air r value table subsection. Air gap or air film 3 4 air space insulating properties. The truth is this studs have an r value of 3 5. Price list leed calculator r value calculator materials calculator bim model downloads.

U factor is a measure of a component assembly in its conductive and radiate capacities. Does not consider presence absence of reflective barriers. As a benchmark one inch of solid wood has an r value of 1. The higher the r value the better the thermal performance of the insulation.

See the department of energy s doe ranges for recommended levels of insulation below. Also included is the hugely helpful insulation zip code calculator that spells out the suggested amount of r value necessary for the different portions of a structure like foundation interior and exterior walls attic and more. 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. The table below shows what levels of insulation are cost effective for different climates and locations in the home.

Product documentation download documents. Typically a higher insulation r rating means better climate control and better energy efficiency for your home. An r value tells you how well a type of insulation can keep heat from leaving or entering your home. 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.

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. Along with knowing the r value of a particular insulation it is also important to calculate the r value of a total system. Does not consider internal convection effects.