# Insert Valley Set Grid

* Select a truss system grid (which doesn’t belong to the main roof)
* Select **Insert Valley Set Grid** directly from **Truss+** menu
* A valley set grid will be automatically created

{% hint style="info" %}
**Note:** Roof with a lower ridge is not the main roof
{% endhint %}

![](https://239424168-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FqtUsszuAWXIZhQhrvjnb%2Fuploads%2FZeLDmfzENfjVdAdbgjvV%2F0.jpeg?alt=media)

* It’s not possible to insert the valley set grid to the main roof, as the main roof doesn’t need the valley set grid
* If the selected grid belongs to the main roof, an error message will occur

![](https://239424168-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FqtUsszuAWXIZhQhrvjnb%2Fuploads%2FghhjYve11k7pjO7QSCCB%2F1.jpeg?alt=media)

* To change a parameter of the main roof:
* Click **OK** to close the error message
* Select the truss system grid and go to **Modify Truss System Grid**
* Uncheck the option **Valley trusses will not be used** and click **OK**

![](https://239424168-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FqtUsszuAWXIZhQhrvjnb%2Fuploads%2FCqrlHX3mIUqywGZsTSkj%2F2.jpeg?alt=media)

![](https://239424168-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FqtUsszuAWXIZhQhrvjnb%2Fuploads%2FKKZyW6w1FVIT47j9rQal%2F3.png?alt=media)