There are a few things to consider when creating boundaries for multiple hatches. The first is the size of the boundary. You'll need to make sure the boundary is large enough to accommodate all of the hatches you plan on using. The second is the shape of the boundary. You'll want to make sure the boundary is shaped in such a way that it doesn't interfere with the function of any of the hatches. The third is the location of the boundary. You'll want to make sure the boundary is located in an accessible spot that won't be in the way of anything else. Once you've considered all of these factors, you should be able to create a boundary for multiple hatches that meets your needs.