Short Answer
In early phases (preliminary study/competition), you calculate in vyzn primarily on the basis of reference values via the SIA 2032 preliminary project. Accuracy is a function of data depth, not of the tool: it increases as soon as you store build-ups and materials in the component catalogue and assign model elements. You make uncertainties transparent with the LCA validation and the assignment statistics; the software does not output specific percentage accuracy bands.
Why It Matters
In a preliminary study or competition, detailed build-ups are not yet available, so the results are initially based on reference values. To ensure your results are interpreted correctly, you should disclose which values are reference-value estimates and which are model-based.
How It Works in vyzn
- Reference-value-based calculation: The life cycle assessment of building services and excavation runs via the SIA 2032 preliminary project. SIA 2032 reference values are applied to the reference quantities (energy reference area, areas, volumes); these quantities are automatically taken from the model metrics.
- Manual overrides: You can manually override each position line by line as soon as you have more robust assumptions.
- Component LCA (KBOB 2022): It becomes more accurate as soon as you store build-ups and materials in the component catalogue and assign model elements.
- Making uncertainties visible: The LCA validation reports missing energy reference area, missing KBOB data, empty matrix cells and unassigned elements. The assignment statistics show what share of the elements has already been covered.
- Context in the report: Your results are benchmarked in the report against standard target and limit values (e.g. SIA 2040, Minergie-ECO).
Frequently Asked Questions
Does vyzn output specific percentage accuracy bands?
No. Accuracy depends on data depth; the software does not output percentage accuracy bands.
How do I communicate uncertainties transparently?
Use the LCA validation (missing energy reference area, missing KBOB data, empty matrix cells, unassigned elements) and the assignment statistics. Record in the report which values are reference-value estimates and which are model-based.
How do I increase accuracy as the project progresses?
Override individual positions with more robust assumptions, store build-ups and materials in the component catalogue and assign model elements.
Update (version 1.8.5)
As of version 1.8.5, you can also use the Express function, which automatically creates a first variant to kick off the preliminary project, so you get initial reference-value-based results with less effort before you increase the data depth.