Solid Concrete Wall U Value

The u value can be calculated as.

Solid concrete wall u value.

Reference table for u values u value is the coefficient of transmission i e the transmission of heat through the materials which compose the building s envelope or outer shell. Cellulose blown wall 3 70 vermiculite 2 13 air entrained concrete 3 90 urea terpolymer foam 4 48 rigid fiberglass 4 lb ft3 4 00 expanded polystyrene bead board 4 00 extruded polystyrene 5 00 polyurethane foamed in place 6 25 polyisocyanurate foil faced 7 20 construction materials concrete block 4 inch 0 80. Remember as mentioned above lower u values should mean higher resistance to thermal bridging. For example a building with material with an r value of r 11 converts to an u value of 0 09 1 r or 1 11 0 09.

U value has an inverse relationship to r value. U values of typical building methods u values overall coefficient of heat transmission indicate the heat flow through materials the higher the figure the higher the heat loss. Table 3 shows the approximate percentage of grouted and ungrouted wall area for different vertical and horizontal grout spacings which can be used to. Below are the typical u values you d expect to measure within a solid wall an uninsulated cavity wall and an externally insulated wall of any kind.

As we said before the r value measures the thermal resistance of a material. Concrete block walls u values r values. Additional r value for a masonry wall constructed using these materials needs to add the insulating value of additional wall components typically included such as 1 solid foam polyisocyanurate r 8 extruded polystyrene r 5 expanded polystyrene r 4 or 1 of perlite r 2 7 and for an exterior air film winter no wind r 0 17 an interior. Table 2 lists calculated u factors and r values of various thicknesses of concrete masonry walls for concrete densities of 85 to 135 lb ft 1 362 to 2 163 kg m with various core fills.

A concrete wall with thickness 0 25 m and conductivity 1 7 w mk is used for the default values in the calculator above. The inside and outside surface resistance is estimated to 5 8 m 2 k w. This process uses w m k as units of measurement. 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.

While the values do vary for each particular material and method of construction the following table gives general figures for some common modes of construction. 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. U value calculator for cavity walls how it works it is designed for all users but specifically those who want to make an assessment of the u value achieved with various combinations of block and thermal insulation prior to finalising a wall design.