BTbat 2.1 is a specialized tool developed at HEIA-FR for calculating and analyzing the thermal balance of buildings according to the SIA380/1 (2016) standard. Combining structured Excel workbooks with an online calculation interface, it enables users to define and evaluate the thermal performance of building envelopes in detail.
The workflow begins with the file BTbat2_1.xlsx, where users describe general parameters, façades, roofs, floors, windows, and thermal bridges. A dedicated sheet allows for customized values when operating in comparison or optimization mode. After completing all required data fields, the file is uploaded to btbat.rjrcompag.ch, where the software validates inputs and performs the thermal balance computation.
A complementary file, Fenstertool.xlsx, refines the definition of window properties, frames, glazing, and shading. Results include monthly energy balances, Sankey diagrams, and envelope efficiency labels in compliance with SIA 2031:2016. Designed for engineers, architects, and researchers, BTbat 2.1 provides a precise and flexible environment for optimizing thermal performance and supporting energy efficient building design.
