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.
R value of 12 concrete wall.
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.
Concrete block wall with air in cavities r 2 0.
Block and cavity fill.
102 mm hollow unit concrete masonry veneer.
Concrete block wall with perlite in cavities r 2 9.
0 13 0 64 30.
The schundler company 150 whitman avenue p o.
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.
Box 513 metuchen new jersey 08840 0513.
R values u values coverage charts.
A wall s thermal resistance or its r value is its ability to slow the transfer of heat from one side to the other.
As we said before the r value measures the thermal resistance of a material.
102 152 203 254 and 305 mm backup wythes and a 4 in.
Cellulose blown wall 3 70 vermiculite 2 13 air entrained concrete 3 90.
Concrete block makes a cost effective and structurally sound wall but it has.
Typical residential weight concrete 8 wall r 2 5.
By doubling the thickness of the wall to 16 inches the r value only increases by 0 50.
Concrete block 12 inch 1 28 brick 4 inch common 0 80 brick 4 inch face 0 44.
Cavity wall r values are listed in tek 6 1c r values of multi wythe concrete masonry walls ref.
Concrete sand gravel aggregate.
These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.
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.
R value of building materials material r inch r thick ness fiberglass inch 3 00 1 inch 4 00.
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.