FAQ

Yes. BUILD has released an interim solution for LCAbyg 2023 (version 5.4.0.5) that supports the new climate requirements. The program works as before, but requires importing new, supplementary data files — see the guide on importing and reading the data, since the new data sits alongside the old data in the program.

The files can be downloaded directly from this site — see the guide on LCAbyg 2025 data in LCAbyg 2023.

No. Separate Excel sheets have been developed for these calculations instead, available via the download section — see Excel sheets for transport and construction process.

Please report data errors to lcabyg@build.aau.dk so they can be corrected.

Two issues were fixed: If a construction contained several instances of the same building product with different quantities, these were previously shown with the same quantity in the table overview — this only affected the display, not the calculations, and has now been fixed. In addition, the total climate impact is now shown correctly excluding additions from special conditions in the export to the standard documentation format.

Incorrect visualization in component graphs while building the building model, where the material distribution can appear reversed. In some GenDK constructions, the demolition phase is incorrectly activated, which excludes the A1-A3 phases from the calculation — use 'duplicate construction' and manually disable demolition as a workaround. Rows and columns are missing from the service life table; the full table is available in BUILD REPORT 2021:32.

Yes, among others: Lightweight concrete and gypsum — a unit error prevents inclusion in the calculation (workaround: duplicate and correct the unit). Lightweight concrete constructions incorrectly include reinforcement that is already included in the EPD. The construction 'Columns, concrete frame column 300/300' contains a steel profile instead of reinforcement. Indoor silicate paint has incorrect C3-phase data relative to the generic baseline, and the paint's service life is set to 15 years where it should be 50 years.

Yes: Wastewater A1-A3 is listed as 0.125 kg CO2eq./m², but should be 1.125 kg CO2eq./m². Water stage D is listed as -1.675 kg CO2eq./m², but should be -1.28 kg CO2eq./m².

Yes, but be aware that concrete materials can in some cases lose phases when opening LCAbyg 5.2.1.0 projects in LCAbyg 2023.

Windows: LCAbyg 2023 (5.3.1.3). Mac: LCAbyg 2023 (5.3.1.2).

Yes, LCAbyg 2023 is freely available and free to use.

The latest guide is available online at guide.lcabyg.dk and is also integrated into the program's Help tab. Video tutorials are available on LCAbyg's YouTube channel.

No, projects opened in LCAbyg 2023 cannot be automatically downgraded to LCAbyg 5.2.1.0.

The Mac version (5.4.0.3) is supported. Linux is not currently supported.

Use the scaling button in the top-right corner to adjust the size of the interface.

Yes, several scenarios with the same functional unit can be compared within the same project under 'Building and operation'.

The Mac version required minor adjustments, resulting in version 5.3.1.2 versus Windows' 5.3.1.0 — the database is, however, identical.

Yes, the Norwegian version is adapted to Norwegian standards. Contact firmapost@eba.no for details.

Among other things: an updated library of building elements and building products with more detail; the option to create stages according to both EN15804+A1 and EN15804+A2 (for A2 only the GWP-total indicator needs to be filled in); scaling factors on all stages (useful for e.g. insulation, which requires manufacturer-specific adjustments); filtering of the results view so only selected indicators are shown; a dedicated 'Building Regulations' results page for a simplified overview when documenting for authorities; English language support via settings; import of the ILCD+EPD format (EPD Norge available from January 1, 2023); an interactive error log where you can double-click to navigate directly to problematic fields; opening projects by double-click with a repair function for damaged older projects; keyboard shortcuts for e.g. rename and delete; and an updated Excel export matching the final requirements for reporting to authorities.

No, direct import from LCAbyg 3.2 is no longer supported. Open the project in LCAbyg 5.2.1.0 first, save it, and then open it in LCAbyg 2023.

Following updated DGNB standards (March 2023), this calculation type has been removed. New certifications should use the 'Building Regulations' calculation type.

Results in LCAbyg are rounded using 'banker's rounding', where x.5 rounds to the nearest even number — this can cause minor deviations in sums.

Incorrect naming of custom building elements, constructions, products, or stages can prevent PDF export. Update to the latest version of LCAbyg.

Yes, charts can be saved as SVG files under Analysis and report.

Enter information from top to bottom, avoid whitespace errors when copying data, and use a comma (not a period) as the decimal separator.

Add generic windows as a supplement with a delayed start after 25 years and a matching service life.

Yes — some EPDs use a period instead of a comma as the decimal separator, which can inflate results if copied directly.

Yes, GenDK has been updated to 'Appendix 2, Table 7: Generic database 2023' with data from EPD Danmark. Projects from earlier versions may therefore show significantly different results when opened in LCAbyg 2023.

EPD-Norge, Digi ECOSMDP (incl. EPD Danmark), and The International EPD System (Environdec).

Missing data in the digital format requires manual EPD entry via stage creation — see section 5.4.1 in the user guide.

Mass factors from the PDF version can be added manually. Do not use calculation results that contain warnings.

Successfully imported EPDs are available in the building elements or stages library, accessible via the book icon. Search by EPD name or operator.

Different operators use different categorizations. The default assignment can be imprecise — recategorize manually to make it easier to find later.

Digitized EPDs that only specify a year default the date to January 1. Check and correct the date against the PDF version.

Importing ILCD+EPD in versions before 5.4.0.4 with incomplete EPDs can produce 'NaN'. Update to the latest version, or fill in the missing stage fields.

Yes, export the customized product to a file and import it in the new project — see section 5.3 in the user guide.

JSON (JavaScript Object Notation) is a format for storing and transporting data. The format makes it possible to build third-party integrations outside LCAbyg's regular interface. See the webinar about the json format on LCAbyg's YouTube channel.

Yes, an English guide to json projects can be downloaded. We continuously update the user guides and the three json guides — older versions can still be used, even though they don't describe the newest features.

An empty example project is included in the zip folder when you download the json guide. It illustrates the import process.

Import the json project into LCAbyg incrementally. The download package includes a debug version (lcabyg_debug.exe) that prints error messages in the terminal. Note: LCAbyg won't work if you click into or type in the terminal — restart LCAbyg after making changes.

The setup of engine.yaml was changed — see step 3.3, page 15 in the json guide.

This is often due to version mismatches between the example project and LCAbyg, including changes to 'CategoryToStage' between version 5.2.0.1 and 5.2.1.0.

Projects that only use the gen_dk library don't export any constructions, since these are already built into LCAbyg.

Search the json file, for example with Notepad++, to check that UUIDs are correctly and fully specified.

This occurs when the same unique ID is used multiple times — check for duplicates.

When you delete a node, the associated edges must also be removed — especially those with amount: 0.

The Excel Lite tool can be used to build the building model via Excel — intended for the early design phase and faster import of the building model. The tool is under continued development; feedback can be sent to lcabyg@build.aau.dk.

Yes, an introduction and help are available in a worksheet within the Excel file itself that you download.

The Excel Lite tool currently doesn't support CSV import on Mac. This is planned for future development.

If you want to copy a row, insert it at the bottom, below the existing rows, rather than trying to insert it elsewhere.