R Value For Concrete Basement Walls

Concrete block makes a cost effective and structurally sound wall but it has little thermal resistance.

R value for concrete basement walls.

Concrete or concrete block walls have the same r value as a 1 9cm thick particle board. 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. The table below shows what levels of insulation are cost effective for different climates and locations in the home. 0 13 0 64 30.

It s up to you to decide the r value of your insulation. In climate 4c the 2012 irc requires a minimum of r 15 for basement walls assuming that we are talking about continuous rigid foam or spray foam insulation the best approach. The r value of an uninsulated 8 inch thick basement wall built using normal weight concrete is 1 35 based on data from the 1993 american society of heating refrigeration and air conditioning engineers handbook. Generally zones 1 and 2 cover the southern states which suggest no necessary values to r 10 for basement walls.

Depending on the density of the blocks an 8 inch thick block wall without any other type of. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. Zones 3 and 4 include the midwest and northern regions requiring r 10 to r 19 values. Extremely northern regions and high elevations are zone 5 requiring r 15 to r 19 values.

The value of basement insulation in cold climates if you had a 20 x 30 6m x 9m basement with concrete or concrete block walls your heat loss could easily be over 1 million btus per day through the walls. By doubling the thickness of the wall to 16 inches the r value only increases by 0 50. 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.

In one step epitome foundation composite walls incorporate r16 5 insulation vapor barrier top plate and stud framing within a 9 high durable basement wall structure. Typical residential weight concrete 8 wall r 2 5. That s a minimum r value.