ARCC 3202 Chapter Notes - Chapter 11: Sealant, Solar Gain
Document Summary
Width of sealant joint is dependent its movement capability and the expected. Maximum joint width=50mm (size is limited by sagging before it cures) Depth of a sealant = half the joint width. Too deep and it will disconnect from the sides, no longer performing as an adhesive. Too shallow and it will tear apart. Sealant must only be bonded to the surfaces on two opposite sides. Other faces left free to deform without localized stress. Foam-plastic backer rod must be used as a bond breaker the middle part of sealant. Gives sealant a narrow middle to minimize stress. Must be 25-50% larger than the joint width. Windows can lose up to 37% of heat in energy efficient homes. Combatted by filling glazing units with gas. Calculates er (energy rating number) for the entire window. Includes solar gains, heat losses and infiltration losses. Limitations: not valid for sloped glazing and skylights or commercial glazing.