Unlike art museums which are devoid of windows, high-end residential construction often has high glass to wall ratios. This is challenging in areas where there are are seasonal cold, damp and humid conditions. To compensate seasonally adjusted relative humidity set points come into play to maintain acceptable conditions for artwork and high-value collectibles in residential interiors.
Architects and designers prefer the minimalistic profile of steel and Jansen has excellent high-performance systems. However, all multiple true divided lights can be, shall we say, "tricky". Published u-values are often deceptive because they ignore the two-inch outer perimeter and only measure at the center of the glass. As a rule, R-values on walls are high, and windows are much lower, expressed in u-values. The lower the u-value, the better. Heating glass can create a u-value near zero, placing the R-value of IQ Radiant Glass windows on par with the value of the walls. IQRG helps eliminate condensation with its ability to adjust for changes in specific interior zones, augmenting a central system. Since IQRG uses radiant heat, there is almost no convection. The concept behind central humidification is to maintain a nearly constant air condition: saturated air with a dew-point temperature just above that at the lowest acceptable space temperature and lowest acceptable relative humidity, in our case, 70°F (21.1°C) and 45% relative humidity.
For zones that are unoccupied with low cooling loads, the resulting space condition is the “Unoccupied” point in Figure 2.
In all cases, seasonal or by activity levels, individually monitored heating glass zones, controlled by the building management system will help maintain desired levels of temperature and humidity.