How to create a new Roof catalog Item?
The best approach will be to duplicate an existing item in the DataGoup Catalog and then modify as needed :
1) Open Catalog Editor:
2) Right-click on the Roof catalog Item and select "Duplicate".
3) Name the duplicated Item accordingly and set the property values as needed.
4) Now you will see the new Roof catalog item in the DataGroup Catalog Editor and available for placement in the Roof Builder tool.