A door drop is a custom modification that lowers the greenhouse door into the foundation (or allows the door to be flush with the ground). Prior to manufacturing the greenhouse, Charley’s Greenhouse will ask for the dimensions of the “drop,” which is the total height of the foundation. (Foundation could be a concrete footing, one row of 4×4’s, or a custom rock wall for example). We will place an order for a custom piece of glass or polycarbonate to install above the door for a perfect fit!