12 Concrete Wall R Value

The reason that it is important to make a good estimate for the current r value for uninsulated spaces is that small changes in r values result in large changes in heat loss when the total r value is low.

12 concrete wall r value.

Concrete block wall with perlite in cavities r 2 9. Concrete sand gravel aggregate. Concrete block wall with air in cavities r 2 0. The r values u factors listed in this tek were determined by calculation using the code recognized series parallel also called isothermal planes calculation method refs.

Typical residential weight concrete 8 wall r 2 5. 0 13 0 64 30. 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. Block type density fill r in 32 x 48 48 x 48 48 x 72 72 x 72 problock 85 pcf 4 6 0 224 0 199 0 183 0 166.

Cavity wall r values are listed in tek 6 1c r values of multi wythe concrete masonry walls ref. 8 inch problock 12 inch problock. 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. R inch r thick ness insulation materials fiberglass batt 3 14 fiberglass blown attic 2 20 1 fiberglass blown wall 3 20 rock wool batt 3 14 rock wool blown attic 3 10 rock wool blown wall 3 03 cellulose blown attic 3 13 cellulose blown wall 3 70 vermiculite 2 13 air entrained concrete 3 90 urea terpolymer foam 4 48.

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 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. You will notice in the findings shown in the isothermal analysis that the thermomass wall panel has a material r value of r 11 49. A wall s thermal resistance or its r value is its ability to slow the transfer of heat from one side to the other.

By doubling the thickness of the wall to 16 inches the r value only increases by 0 50. Concrete block makes a cost effective and structurally sound wall but it has. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. The isothermal analysis shows 90 thermal loss in this wall panel with.