Roof Insulation R Value Chart

Insulation level are specified by r value.

Roof insulation r value chart.

The common denominator among varieties of insulation is the r value. A higher r value means that the insulation will do a better job of holding in conditioned air whether that s heat in the winter or cool air in the summer. Polyiso insulation thickness r value chart. The higher the r value the better the thermal performance of the insulation.

The increase r21 r3 exactly 18 the value by which you are increasing the r value. Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. As an example a 1 board label will include information from lttr s770 03. Carlisle s tapered insulation helps promote rooftop drainage while providing excellent insulating value.

Jm sheathing r values will not change. Achieving greater r values in attics. R3 r18 r21 total roof r value. For a very good introductory overview article on r value see r values over at the website of.

Polyiso is the industry s premier roofing insulation. 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 q4 2013 jm will modify its packaging to reflect lttr values by both test methods. R value of various materials.

The table below shows what levels of insulation are cost effective for different climates and. 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. Calculate percent improvement in r value. 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.

Understanding r value thursday december 13 2018 what does r value mean. Recommended home insulation r values. R value is a measurement of thermal resistance and measures the ability of heat to transfer from one side of an object to another. You should of course see the manufacturer provided technical data sheet for the r value of specific products.

R value is a measure of insulation s ability to resist heat traveling through it. In comparison an inch of blown fiberglass insulation has an r value of 3 1 3 4 and. Jm s wall sheathing line ap foil and ci max are not governed by lttr test methods and have different r value measurement standards. The following table provides typical r values and rsi for various materials these r values were taken from manufacturer technical data sheets and are the reported r values per inch of actual products.

Tapered polyiso minimizes the negative. To learn more about r value see roof online s r value page.