With a bit of work and planning you can customize your layout. This link will bring you to the demo of RadTileView. There you can see all the different examples by dropping down the "Other TileView Examples" button in the toolbar.
Next, go to this link. There you will find the official documentation on the control, specifically Customize Position. Look at the left column and notice the expanded TileView node. In there you can find instructions and getting started code.
Personally, I would use RadDocking as a more customizable solution for your needs. In this example, you can see how using SplitContainers would give you what you're looking for.