How Much Is Necessary?
Skylite Construction LLC.
- How much Spray Polyurethane Foam Perimeter Insulation is necessary?
- A minimum of one inch of sprayed in place polyurethane foam must be
installed to achieve the air infiltration control so necessary to reduce
energy cost. Additional thickness may be required to seal voids, cracks and
other imperfections in the building envelope.
The specific thickness of insulation depends on local codes, personal
preferences, where the house is located, and the type of construction being
utilized. Further, the thickness of the sprayed polyurethane foam can vary if
necessary to complement other insulation materials of choice, i.e., glass
fiber, sprayed cellulose or mineral wool, to achieve the required "R" value.
The thermocline map shown provides a guide for "R" values for ceilings, walls
and floors for residences located throughout the U.S. The six ranges are based
on climatic temperature extremes and heating requirements. Cooling
requirements for these same areas generally require less insulation value.
Hence, if the home is insulated for efficient heat needs, cooling efficiencies
will certainly be met.
Spray applied polyurethane foam insulation my be
applied to any wall configuration, ceilings, sub-floors, foundations and roofs
(as a part of a roofing system). In all such cases it will seal off air
infiltration in addition to meeting the insulation needs to make a home energy
efficient. Once a house has been framed and enclosed with exterior siding,
spray polyurethane foam may be applied between the studs. As little as 1/2" of
spray polyurethane foam insulation can provide significant "R" value in
addition to controlling air infiltration.
Follow proper electrical and
plumbing preparation, and clean-up procedures before applying an approved
15-minute finish rating thermal barrier such as 1/2" gypsum drywall, or
equivalent. - Definitions
- "R" Value: A measure of the resistance of a material to the passage
of heat. The less heat that a material will allow to pass through it, the
higher the material's "R" Value.
- "U" Factor: Measures the amount of heat passing through a composite
of materials. To determine "U" divide '1' by the total of the "R" values.
Example: The "U" of a total "R" value of 23.75 is .042.
