Depending on the density of the blocks an 8 inch thick block wall without any other type of.
R value for concrete basement walls.
Zones 3 and 4 include the midwest and northern regions requiring r 10 to r 19 values.
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.
The table below shows what levels of insulation are cost effective for different climates and locations in the home.
These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.
0 13 0 64 30.
Concrete sand gravel aggregate.
You can install more insulation than that if you want to.
Concrete block makes a cost effective and structurally sound wall but it has little thermal resistance.
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.
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.
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.
Generally zones 1 and 2 cover the southern states which suggest no necessary values to r 10 for basement walls.
8 thick concrete slab or foundation wall has an r value of about 1 04 30 while lightweight aggregate filled 8 thick concrete has an r value of about 2 18 30.
By doubling the thickness of the wall to 16 inches the r value only increases by 0 50.
That s a minimum r value.
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.
R value is a measure of insulation s ability to resist heat traveling through it.
Typical residential weight concrete 8 wall r 2 5.
Concrete or concrete block walls have the same r value as a 1 9cm thick particle board.