What other factors could require me to need a permit?

Just like any building structure, you may need a permit

Depending on your local planning department and what you are adding to your greenhouse, there could be additional permitting required.

The main ones we see from customers are if they look to add utility hookups including electrical, water, and any possible gas or propane systems.

It's a good idea to think about whether you will have lighting in the greenhouse overnight that may impact neighboring houses too.