Building Concepts Windows
Additional Resources
BC Exercise 1 Single Pane Window R-value
Find the center of glass R-value for a single-pane window. Include the standard values for interior and exterior air films. Assume glass is 3mm thick with a thermal conductivity of 0.8 W/m/K.
BC Exercise 2 Effective Boundary Layer Thickness
The R-value of the interior air boundary layer is 0.12 m^2 K/W and the conductivity of air is 0.026 W/m/K. What is the effective thickness of the still layer of air next to an interior wall. (Effective means if we have an ideal slab of still air and then moving conductive air. The reality is that there is a transition.)
BC Exercise 3 Triple Pane Window R-value
Let’s model the triple pane window as two pieces of 3mm glass and an interior of layer of 1mm glass. For the interior and exterior air films, use the standard values. For the air films inside the window, assume argon, with an argon film thickness of 3mm. Argon has a thermal conductivity of 0.016 W/m/K.
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File "source.py", line 11, in <module>
import cairo
ModuleNotFoundError: No module named 'cairo'Energy Savings
Given a number of heating and cooling degree days, what is the energy savings per year of a triple pane window relative to a single pane window. Your answer may be in therms for heating and in kWh for cooling.
Window Heat Loss
You have a 0.5 m^2 window with an average US R-value of 2 (about 0.36 metric R-value). This window is exposed to 20 heating degree days over the course of a night in units of ^\circ C\cdotdays.
How much energy in joules is lost over the course of the night?
Solar Window Radiation
You have a large south-facing vertical window measuring 2 meter by 5 meters. The window has an average US R-value of 3. In our local climate, we assume a transmission of 7 MJ per square meter per day transmitted through this window.
How much energy is transmitted through the window over one day?