Masonry Magazine August 1988 Page. 19
TABLE 3
| | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| :-- | :------------------------------ | :---- | :-- | :-- | :-- | :---- | :---- | :-- | :---- | :---- | :- |
| 1 | Material | T.R. | % | T.D. | F | SV.P. | V.R. | % | V.P.D. | A.V.P. | |
| 2 | Inside Air | 0.00 | 0 | 0 | 72 | 0.791 | 0.008 | 0 | 0 | 0.577 | |
| 3 | Inside Air Film of Still Air | 0.68 | 5 | 3 | 69 | 0.714 | 0 | 0 | 0 | 0.577 | |
| 4 | 1/2" Drywall (Gypsum) | 0.45 | 4 | 2 | 67 | 0.667 | 0.027 | 1 | 0.005 | 0.572 | |
| 5 | 6" Block | 1.53 | 11 | 6 | 61 | 0.540 | 0.300 | 7 | 0.037 | 0.535 | |
| 6 | 1½" Rigid Insulation Expanded Polyurethane | 9.38 | 69 | 38 | 23 | 0.119 | 2.34 | 59 | 0.314 | 0.221 | * |
| 7 | 1" Air Space | 0.97 | 7 | 4 | 19 | 0.098 | 0.008 | 0 | 0 | 0.221 | * |
| 8 | 4" Brick | 0.44 | 3 | 1 | 18 | 0.093 | 1.3 | 33 | 0.176 | 0.045 | |
| 9 | Outside Air Film 15 MPH | 0.17 | 1 | 1 | 17 | 0.089 | 0 | 0 | 0 | 0.045 | |
| | Total | 13.62 | 100 | 55 | | | 3.983 | 100 | 0.532 | | |
ABBREVIATIONS
Thermal Resistance
Termperature Difference (°F)
Saturated Vapor Pressure (in Inches Mercury)
Vapor Resistance (in Inches Mercury)
Vapor Pressure Difference (in Inches Mercury)
Actual Vapor Pressure (in Inches Mercury)
Inside Air Temperature (°F)
Outside Air Temperature (°F)
Relative Humidity Inside
Relative Humidity Outside
NOTES
See Table 1 of Technical Notes 4 Revised.
See Table 1
See Table 2
Information Required for this example
Ti = 72
To = 17
RHI = 73%
RHo = 50%
SUMMARY
The analysis procedure presented in this Technical Notes may be used as an indicator of where condensation may occur in a wall section. It may also be used to analyze the effect on condensation potential of varying wall components and vapor barriers. The information contained in this Technical Notes is based on the available data and experience of the technical staff of the Brick Institute of America. This information should be recognized as recommendations and should be used with judgment. Final decisions on the use of the information discussed herein are not within the purview of the Brick Institute of America, and must rest with project owner, designer or both.