New Features

Below is a list of the new features added with each new version of Lesosai.

New features of Lesosai version Lesosai 2019

  • Minergie 2019 new limit value
  • Dimensioning floor heating vers. 2
  • New CECB export and import vers. 5
  • RT2012: Neu motor version 8
  • RGD 2019 Luxembourg
  • Improved many reports
  • Improvement in project and database tree
  • New glazing and windows database

More information in French: nouveautés Lesosai 2019

New features of Lesosai version Lesosai 2018

  • Minergie ECO 2018 and KBOB2016 + Addendum
  • Dimensioning floor heating
  • New CECB Plus export and import
  • Improved many reports
  • Improvement in tree project
  • Improvement in project database tree
  • Improved SIA385/2 Hot water
  • Autosave of projects
  • 32bit and 64bit Version

More information in French: nouveautés Lesosai 2018

New features of Lesosai version Lesosai 2017

  • Luxembourg, Lenoz certification: grey energy and survey
  • Minergie 2017
  • SIA380/1:2016
  • SIA387/4:2017
  • SIA385/2:2015
  • ECO data: ÖkobauDat
  • EN ISO 13770: perimeter insulation
  • update windows glazings
  • Improved boiler sizing calculation

More information in French: nouveautés Lesosai 2017

New features of Lesosai version 2016

  • Minergie ECO 2016 limit value
  • Mienrgie ECO 2016 questions
  • Optimisation Tool
  • SIA 2024 version 2015
  • More confort calculations
  • Export to Polysun

More information in French: nouveautés Lesosai 2016

New features of Lesosai version 2015

  • New label DGNB, SNBS, Effiniergie, BREEAM
  • New reports EN-1a, EN-2b
  • New RT2012 motor
  • Improved gbXML import
  • Improved exports
  • Improved data analysis
  • Export data for prices calculations

More information in French: nouveautés Lesosai 2015

New features of Lesosai version 7.4

  • Minergie-ECO® 2012 label
  • import gbXML file format that is generate by AutoCAD Revit, Google Sketchup (with Plugin) and Archicad (with Plugin)
  • Compatible according to Technical Manual SIA2032 "L'énergie grise dans le bâtiment"
  • Natural lighting following Minergie-ECO®
  • Copy and rename an item in the database of materials
  • Export to Excel Minergie® and Minergie-P® files (version 12)
  • Copy the windows between inventories (with thermal bridges)
  • Improved management models of elements
  • Allow to create a sentence type, save and read (first comment)
  • Translation of the Help in English
  • RT Renovation (France) with Th-C-E ex
  • Import Carnaval data

More information in French: nouveautés Lesosai 7.4

New features of Lesosai version 7.0

  • A wizard that allows you to quickly model a building, ideal for pre-projects and renovation diagnostics
  • Integration of the module Polysun Inside® (, for simulation, calculation and dimensioning of solar thermal
  • The possibility to create variants of a project
  • L’intégration du catalogue des ponts thermiques de l’OFEN
  • Integration of the 'OFEN' thermal bridges catalogue
  • Inclusion of an easy-to-use window frame calculation tool for use in solar calculations
  • More options for hourly calculation (earth pipes ('puits canadiens'), fan coil units, natural ventilation according to SIA2023
  • Automatic blinds: resistance of blinds taken into account in hourly calculations
  • Calculations with solar radiation in all directions
  • New equations to account for shading from side screens (like RT2012)
  • Updates to the module ECO+® for lifecycle analysis using LESBAT from HES d’Yverdon (
  • Integration of the SIA2032 standard for the ECO+® module
  • The new version of the weather module, Meteonorm® (, which lets you create a weather station anywhere in the world (except at the poles !…)
  • Calculation of temperature distribution
  • Revised data entry
  • Results screens easier to read, and include more information
  • links to the repository are maintained when copying elements with sub-elements (for example: wall with windows and thermal bridges)
  • Intelligent usage of default values
  • Easier introduction of data for underfloor heating systems
  • Visual feedback of entered data
  • New results for the management of window gains
  • New catalogue of more than 90 wall constructions (years 1930, 1980, class B, class A)
  • New catalogue of doors
  • Faster creation of projects with many buildings
  • Improved general presentation (more graphical)
  • Updated and improved help files

More information in French: nouveautés Lesosai 7.0

New features of LESOSAI 6.0

  • SIA 382/1
  • SIA 380/1 2009
  • SIA 2028
  • Modular system
  • U-value calculation of inhomogeneous elements and catalogue of construction elements (integration of USai. See
  • Connection to the database
  • SIA380/4 calculations, lighting and ventilation
  • Hourly calculations, air-conditioning
  • Meteonorm, weather data for all locations
  • New forms C, G Swiss-German cantons and Tessin
  • Building life cycle calculations
  • RT2005 (uncertified)
  • RGD Luxembourg
  • EN 12831 / SIA384.201 heat load calculation per room
  • New help
  • SIA2031 buildings certification
  • Ability to export to Minergie version 10
  • Abiltiy to export hourly data to MS Excel
  • New element-management interface
  • New GUI
  • New elements: internal, local walls
  • Solar photovoltaic
  • Solar thermal
  • Technical systems
  • Ability to change model at any time
  • Thermal bridges in windows
  • SIA2031 label of certification


New features in LESOSAI 5.7

  • SIA 380/1 (2007)
  • New glazing database (2008)
  • E1 et E2 Forms (2008).


New features in LESOSAI version 5.6

  • E2 Form
  • Ability to export results to excel files: E2.A.xls et Rechnach.xls.
  • Simplification of data entry for Luxembourg.
  • Forms for cantons of Eastern Switzerland
  • Ability to save the name of the assessment officer on the building screen
  • Added the value limit of 80% for the cantons
  • The form for the canton of Tessin.
  • The Italian directive DLGs 192, DLGs 311 and calculation of Cd with report(2007 values).
  • New report showing wall and glazing data.
  • New glazing database, with more than 260 elements, according to new standard EN673, as required by the CRDE.
  • New database of Swisspor materials.
  • Ability to export to pdf.
  • Improvement of the U-value calculation screen, in particular the searching of materials.
  • Ability to print official SIA 380/1 and E1 reports, by using the target value required by several French cantons for public buildings.
  • Minergie® P verification.
  • New update tool.
  • New glazing selection tool.
  • Improved the interface for adding windows (calculations based on combination of glazing properties and shading fraction).
  • Calculation of intermeiten heating for EN 13790.
  • Real time calculation of B value in envelopes.
  • Calculation of the heating power according to EN 12831 et SIA384.201.
  • Improved the reports
  • English language version (text changes)
  • Official weather data: Switzerland, Italy, France, Germany, Romania and Luxembourg.
  • More information calculated in real time in varous screens.
  • Temperature in January of unheated zones
  • Solar heating calculations of the whole building and of individual zones.
  • Ability to introduce a window or door and specify the number of identical doors.
  • Improved the weather screen
  • Ability to print comparison reports in kWh (item in options menu)
  • The solar thermal report page contains more information
  • Improved calculation speed for large projects.


New features of LESOSAI version 5.0

  • Ability to export results to excel files E2.A.xls and Rechnach.xls.
  • Forms for cantons of Eastern Switzerland
  • Verification according to SIA 380/1 version 2001 and Minergie®.
  • Calculation of multi-zone buildings according to the most precise method outlined by SIA 380/1.
  • Integrated calculation of the thermal coefficient of transmission of walls, with a quick estimate of the risk of condensation.
  • Integrated calculation of the shade over glazings and other passive solar devices.
  • Integrated calculations of heat losses through the ground, according to EN 832 or SIA 380/1.
  • New table of glazings, with the ability to create new glazings.
  • New table of materials, with the ability to create new materials.
  • Easy comparison between the buildings studied and standard alternatives.
  • Predimensionning of the boiler.
  • library of construction elements.
  • Improved look of reports and graphs.
  • Simplified installation using the Delphi programming language
  • Project files contain all information relevant to the project, and can be easily transferred for another person's use.
  • Report E1 of CRDE (08/04/2003)