Software for Building Physics Experts
WINSLT®
Expert Software for Your Success
WINSLT® is expert software for the standards-compliant calculation of optical, solar, and thermal properties of glazing in combination with solar shading systems.
Why WINSLT®?
Certified Software
Certified and tested by independent testing institutes
Internationally recognized
Results generated by our software are internationally recognized
Easy to Use
Designed to be intuitive and user-friendly
Always Up to Date
Regular updates and new solutions, always in line with the latest standards
Partnerships
Strong partnerships with Bundesverband Flachglas, VFF, and Metall und Mehr
Customer Satisfaction
a reliable partner for long-term customer satisfaction
Validated
Validated for calculations of optical, solar, and thermal performance characteristics
Professional Calculation
Ug, g, reflectance, absorptance, transmittance, gtot, and SHGC values
Powerful Features
Automated generation of Declarations of Performance and CE marking documentation
Certified Software
Certified and tested by independent testing institutes
Internationally recognized
Results generated by our software are internationally recognized
Easy to Use
Designed to be intuitive and user-friendly
Always Up-to-Date
Regular updates and new solutions, always in line with the latest standards
Partnerships
Strong partners such as the German Flat Glass Association, VFF, and Metall und Mehr
Customer Satisfaction
a reliable partner for long-term customer satisfaction
Validated
for calculating lighting, solar, and thermal performance parameters
Professional Calculation
Ug value, g value, reflectance, absorption, transmittance, gtot value, SHGC value
Powerful Features
with a Declaration of Performance and CE marking
WINSLT®
WINSLT® is the professional software solution for glass manufacturers, solar shading manufacturers and planners for the precise calculation of the interaction between glass and solar shading systems. The software quickly determines all relevant optical, solar and thermal parameters (such as U_g, g and g_total values) for glazing configurations of any complexity.
WINSLT®
WINSLT® is the professional software solution for glass manufacturers, solar shading manufacturers and planners for the precise calculation of the interaction between glass and solar shading systems. The software quickly determines all relevant optical, solar and thermal parameters (such as U_g, g and g_total values) for glazing configurations of any complexity.
WINSLT® – also available as an online version
Use WINSLT® Online directly in your browser with no local installation required. The online version enables fast calculation of the optical, solar, and thermal performance characteristics of glazing systems in combination with solar shading. Values such as Ug, g, gtot, and SHGC can be easily calculated and used for planning, consulting, and documentation.
Applications & Features
WINSLT® supports the precise calculation of light, solar, and thermal performance parameters for glazing systems with and without solar shading. Key properties such as reflectance, absorptance, solar light transmission, Ug, g, gtot, and SHGC values are accurately determined and clearly presented.
Using the extensive WINSLT® spectral database, glazing configurations can be created and combined quickly and flexibly. Coatings, laminated glass, shading systems, screen printing, and special glazing configurations are modeled in accordance with relevant standards, making WINSLT® an efficient solution for product development, planning, performance verification, and technical documentation.
Spectral Data Calculation
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WINSLT® calculates reflection, transmission, and absorption based on spectral data. This allows for a detailed analysis and comparison of the light, solar, and thermal properties of glass structures.
Flexible Glazing Configurations
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Design and calculate custom glazing configurations with multiple glass panes, coatings, and gas- or vacuum-filled cavities. This allows different glazing variants to be evaluated quickly.
Solar Shading & Blinds
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The slat module allows you to model venetian blinds and solar shading systems based on their width, spacing, angle, and the position of the sun. This enables realistic calculation of gtot values.
Component Database
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WINSLT® provides access to spectral data from glass and solar shading manufacturers. Users can also import their own data and use it in new calculations.
Automated Product Declaration
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Calculated performance values can be used to generate Declarations of Performance, CE marking documentation, and technical documentation. This reduces the effort required for documentation and verification.
Compliance with International Standards
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WINSLT® supports calculations in accordance with relevant standards, including EN 673, EN 410, EN ISO 52022-3, ISO 15099, and ASHRAE requirements. This ensures traceable results for planning and verification.
Spectral Data Calculation
Learn More
WINSLT® calculates reflection, transmission, and absorption based on spectral data. This allows for a detailed analysis and comparison of the light, solar, and thermal properties of glass structures.
Flexible Glazing Configurations
Learn More
Design and calculate custom glazing configurations with multiple glass panes, coatings, and gas- or vacuum-filled cavities. This allows different glazing variants to be evaluated quickly.
Solar Shading & Blinds
Learn More
The slat module allows you to model venetian blinds and solar shading systems based on their width, spacing, angle, and the position of the sun. This enables realistic calculation of gtot values.
Component Database
Learn More
WINSLT® provides access to spectral data from glass and solar shading manufacturers. Users can also import their own data and use it in new calculations.
Automated Product Declaration
Learn More
Calculated performance values can be used to generate Declarations of Performance, CE marking documentation, and technical documentation. This reduces the effort required for documentation and verification.
Compliance with International Standards
Learn More
WINSLT® supports calculations in accordance with relevant standards, including EN 673, EN 410, EN ISO 52022-3, ISO 15099, and ASHRAE requirements. This ensures traceable results for planning and verification.
Other Software vs. WINSLT®
Function
Other
Difficult to model in compliance with standards
Limited and inflexible data handling
Often limited to national standards
Documents must be prepared separately
WINSLT®
Precise calculations based on slat position and angle
Custom data import and integrated extraction tools
Compliance with internationally recognized standards, including EN, ISO, and ASHRAE
Direct generation of Declarations of Performance and CE marking documentation
Customer Testimonials
“Interpane Glasgesellschaft mbH has been a loyal customer of Sommer Informatik GmbH for many years. After just a short training period, we were able to use WINSLT® for calculations quickly and effectively, which is why we highly recommend this tool.”
Interpane Glasgesellschaft mbH
Interpane Glas Industrie AG is a German flat glass manufacturer headquartered in Lauenförde.
The company manufactures glazing products at ten locations in Germany, Austria, and France.
“WINSLT® is a powerful tool that is very important to us, providing users with professional support when carrying out calculations.”
Bauwerk Engineering Firm
Contact:
Mr. Deckert – info@waermeschutz.cc
The engineering firm has been in business since 1998 and offers services in the fields of building physics and window technology.
Frequently Asked Questions
Do the values calculated with WINSLT® meet the requirements of EN 1279-5, in particular the calculation requirements according to EN 673 and EN 410?
The requirements of DIN EN 1279-5 are met in full, and the calculations in accordance with EN 673 and EN 410 have been certified/validated by ift Rosenheim. These calculations are based on values and spectral data declared by the manufacturers.
Which part of the program can be used to calculate the lighting parameters of insulated glass?
WINSLT® calculates optical, radiative, and thermal performance characteristics of glazing in accordance with EN 673 and EN 410, as well as of glazing in combination with solar shading in accordance with EN ISO 52022-3.
How can custom structures made of polycarbonate be entered?
The program allows users to import custom data for different component types. The spectral data can be easily imported into the program as data sets.
Is it possible to calculate external slats?
Yes. Internal and external slatted solar-shading systems can be calculated with the slat calculation module in WINSLT®. Slat geometry, opening angle, and solar position can be specified. The ventilation conditions in the cavity between the glazing and the solar-shading device can also be defined in detail and taken into account in the energy calculation of the total solar energy transmittance (gtot).
Is the glass database in WINSLT® compatible with the international glass database IG(S)DB?
The “Optical Berkeley” add-on integrates access to spectral data from the IGSDB directly into the SommerGlobal calculation process.
The interface was developed as part of the EQWIN-P research project in collaboration with Fraunhofer ISE and is available as an add-on for the following modules:
- WINSLT®
- WINSLT® 15099
- WINTHS

