> ## Documentation Index
> Fetch the complete documentation index at: https://docs.realtimelca.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Library

> Browse materials and constructions, build collections, and create your own EPDs.

The **Library** is the shared catalog of materials and constructions that your projects pull from when you map a model. From here you can:

* Browse a curated set of **Product EPDs**, **Generic EPDs**, and **Industry EPDs** maintained by Real-Time LCA and your organization.
* Build **Collections** to group the materials your team uses regularly.
* **Create** new materials — either published EPDs you have a document for, or custom (non-verified) entries when no EPD exists yet.
* Inspect **Constructions** that combine several materials into reusable build-ups.

<Frame caption="Library — Materials tab">
  <img src="https://mintcdn.com/real-timelca/bMAMJ-Pe-pcp6ZrR/images/user-guide/Library%20materials%20list.png?fit=max&auto=format&n=bMAMJ-Pe-pcp6ZrR&q=85&s=c227c2fa58acae654d1ef30faf8d3bd1" alt="Library page showing the Materials tab with a list of EPDs and a + Material button in the top right." width="3104" height="2024" data-path="images/user-guide/Library materials list.png" />
</Frame>

## In this section

<Columns cols={2}>
  <Card title="Materials" icon="cube" href="/user-guide/library/materials">
    Browse, search, filter, compare, clone, favorite, and group materials.
  </Card>

  <Card title="Constructions" icon="layer-group" href="/user-guide/library/constructions">
    Explore reusable build-ups composed of multiple materials.
  </Card>
</Columns>

## Switch between Materials and Constructions

The two tabs at the top of the Library switch the list between **Materials** (single products) and **Constructions** (multi-layer build-ups). The search box, filter panel, and toolbar to the right adapt to the active tab.