> 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/components/1-bottom-up/1-layer-impact.md).

# 1: Layer Impact

This component calculates the environmental impact of materials within a layered structure. This includes typical construction scenarios where the materials' impact in the database ("Bezug" in [KBOB](/docs/databases/kbob.md)) is defined per mass.

> **NOTE:** If the selected material does not have its density defined, the result from this component will be 0 as it will be multiplied by the non-existent density. To avoid this, use the [Component](/docs/components/1-bottom-up/2-component-impact.md) impact for cases such as KBOB 12.xxx or KBOB 21.xxx.

**INPUT:**

* The material properties should be connected from the [Material ](/docs/components/0-database/2-material.md)component from the [Database](/docs/components/0-database.md) group.
* The thickness of the material layer is provided in meters.

**OUTPUT:**

Layer (Text) provides the impact headers and values together for better readability, and Layer Properties (Values) is the output that should be used through the workflow.