> For the complete documentation index, see [llms.txt](https://bombyx.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://bombyx.gitbook.io/docs/methodologies.md).

# Methodologies

This section describes the main design-integrated LCA methodologies available using Bombyx. These methodologies are based on the Swiss KBOB database.

## Top-down

This method is useful for early design stages when the construction detailing has not been determined yet, and allows for general overview of the building's embodied impact.

## Bottom-up

This method provides the possibility of detailed LCA and parametric element composition by defining the materials layer-by-layer to create the building element.