10 Concrete Wall R Value

F btu 1 23 m k w an estimate of the building envelope energy use for this structure is approximately 27 800 btu ft 87 7 kwh m as shown in figure 1.

10 concrete wall r value.

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. Recommended home insulation r values. Concrete block wall with perlite in cavities r 2 9. 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.

Make sure your home is properly insulated in all these locations. As we said before the r value measures the thermal resistance of a material. Insulation ratings can be improved by adding more layers of insulation. Concrete block wall with air in cavities r 2 0.

You can mix the type and material of insulation too. Table 2 presents r values of uninsulated concrete masonry cavity walls with 4 6 8 10 and 12 in. 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. The walls have rebar of various diameters imbedded throughout.

The ideal attic insulation r value is different than the ideal wall insulation r value. 102 152 203 254 and 305 mm backup wythes and a 4 in. 102 mm hollow unit concrete masonry veneer. The walls i am working with vary from 6 inches thick for one wall and 10 12 and 14 inches thick for other walls.

If this school is built using single wythe concrete masonry walls with cell insulation only and a resulting wall r value of 7 hrft 2. A wall s thermal resistance or its r value is its ability to slow the transfer of heat from one side to the other. 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. Concrete block makes a cost effective and structurally sound wall but it has.

R value tables traditional three web units. R value is a measure of insulation s ability to resist heat traveling through it. Insulation level are specified by r value. If we increase the r value of the wall to r14 by.

Achieving greater r values in attics.