Exterior Wall And Roof Insulation R Value

These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.

Exterior wall and roof insulation r value.

Basics of faced fiberglass insulation from r 13 to r 19. The table below shows what levels of insulation are cost effective for different climates and. Foam board or insulating boards are rigid panels of insulation that have a high r value. The higher the r value the better the thermal performance of the insulation.

Because they have a high r value and can be used nearly anywhere in your home foam board insulation is one of the most common types of insulation. Recommended home insulation r values. Best for floors foundation and basement walls interior and exterior wall sheathing and low sloped ceilings. You can use the small pressurized cans of foam.

R value is a measure of insulation s ability to resist heat traveling through it. In simple terms r values measure the effectiveness of insulation and a higher number represents more effective insulation. 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. For example if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed in your attic to reach r 30 if you live in zones 2 or 3.

Some installations can yield a higher r value than traditional batt insulation for the same thickness and can fill even the smallest cavities creating an effective air barrier. The r refers to absolute thermal resistance. Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. 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.

R value of various materials. You should of course see the manufacturer provided technical data sheet for the r value of specific products. R value is a standard unit of measurement for determining among many things how effective your insulation will be. For instance if you have a material with an r value of 12 attached to another material with an r value of 3 then both materials combined have an r value of 15.

If your exterior walls are constructed from 2 by 4 inch studs the most insulation that can go into the wall while retaining its r value is r 13 or r 15 as these are both made to fit a cavity 3 1 2 inches deep. Additional r value for a masonry wall constructed using these materials needs to add the insulating value of additional wall components typically included such as 1 solid foam polyisocyanurate r 8 extruded polystyrene r 5 expanded polystyrene r 4 or 1 of perlite r 2 7 and for an exterior air film winter no wind r 0 17 an interior. Note from this. Insulation level are specified by r value.