Mold Resistance

TEMPERATURE AND HUMIDITY INTERACTION, DEW POINT.

The condition for mold formation is warm humid air in proximity to dead organic materials such as wood.

Temperature distribution through our wall was calculated to find any potential mold area. The results are shown below.

The computations were made based on Fourier's law for heat transmission through solids. Humidity transmission was estimated based on the relative porosity of the materials and published data.

The assumed condition were:

Exterior insulated wall with rigid insulation and gypsum boards on the interior.

Exterior (ambient) temperature 95º F @ 90% humidity.

Interior (room) temperature 75º F @ 25% humidity.

These graphs indicates that the area that show the combination of temperature and humidity most appropriate for mold growth is the interface of the concrete with the polystyrene. However, since the concrete was poured this area does not have any air.

The cavity behind the sheetrock, where air and wood (furring) are present exhibits low temperature and low relative humidity.

The conclusion of this study is that mold can NOT develop in walls built with our forms.

Dow Chemical - Dewpoint Analysis Chart (click HERE for complete PDF).