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.
R value of 8 concrete wall.
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 insulation may be poured directly into walls or emptied into a simply wood or metal hopper which can be slid along the wall to direct the free flowing perlite into cores of cavities thus insulating all voids and air pockets.
Concrete block wall with perlite in cavities r 2 9.
Block thickness in inches.
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.
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.
For example if you miss the r.
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.
Concrete block walls u values r values.
Cavity wall r values are listed in tek 6 1c r values of multi wythe concrete masonry walls ref.
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.
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.
0 13 0 64 30.
Concrete block wall with air in cavities r 2 0.
R values for concrete masonry walls exposed both sides density r value increase problock 85 pcf 10 69 226 problock 105 pcf 8 27 152 traditional 3 web nw cmu 130 pcf 3 28 0 problock 85 pcf 18 14 264 problock 105 pcf 13 94 179 traditional 3 web nw cmu 130 pcf 4 99 0.
Typical residential weight concrete 8 wall r 2 5.
Concrete sand gravel aggregate.
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.