(For NFRC Certification and modeling complex glazing systems)

For modeling vacuum glazing, deflected glass, vertical venetian blinds, cellular shades and perforated screens
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Two-Dimensional Building Heat-Transfer Modeling

THERM is a state-of-the-art, Microsoft Windows™-based computer program developed at Lawrence Berkeley National Laboratory (LBNL) for use by building component manufacturers, engineers, educators, students, architects, and others interested in heat transfer. Using THERM, you can model two-dimensional heat-transfer effects in building components such as windows, walls, foundations, roofs, and doors; appliances; and other products where thermal bridges are of concern. THERM's heat-transfer analysis allows you to evaluate a product’s energy efficiency and local temperature patterns, which may relate directly to problems with condensation, moisture damage, and structural integrity.

THERM’s two-dimensional conduction heat-transfer analysis is based on the finite-element method, which can model the complicated geometries of building products. See Components for more details.

THERM is a module of the WINDOW+5 program under development by LBNL. WINDOW+5 is the next generation of the WINDOW software series and is being developed for the Microsoft Windows™ operating environment. THERM's results can be used with WINDOW's center-of-glass optical and thermal models to determine total window product U-factors and Solar Heat Gain Coefficients. These values can be used, in turn, with the RESFEN program, which calculates total annual energy requirements in typical residences throughout the United States.


System Requirements

Sample Screen Shots

Click on image to view the screen shot.

Sample Cross Section
(Aluminum Slider Window Frame)
Sample Isotherm Results
(Aluminum Slider Window Frame)
Sample Color Infrared Results
(Aluminum Slider Window Frame)
Sample Curtainwall with Bolt Cross Section with Infrared Results

Updated: 03/11/14