10 Concrete Wall R Value

The walls have rebar of various diameters imbedded throughout.

10 concrete wall r value.

Achieving greater r values in attics. 102 mm hollow unit concrete masonry veneer. Table 2 presents r values of uninsulated concrete masonry cavity walls with 4 6 8 10 and 12 in. A wall s thermal resistance or its r value is its ability to slow the transfer of heat from one side to the other.

Insulation level are specified by r value. Recommended home insulation r values. Insulation ratings can be improved by adding more layers of insulation. Concrete block wall with air in cavities r 2 0.

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. 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. The ideal attic insulation r value is different than the ideal wall insulation r value. By doubling the thickness of the wall to 16 inches the r value only increases by 0 50.

You can mix the type and material of insulation too. 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. Concrete block wall with perlite in cavities r 2 9. R value tables traditional three web units.

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

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 i am working with vary from 6 inches thick for one wall and 10 12 and 14 inches thick for other walls. 102 152 203 254 and 305 mm backup wythes and a 4 in. R value is a measure of insulation s ability to resist heat traveling through it.

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.