The size of your greenhouse film can be determined by measuring the length and width of the growing structure that you wish to cover.

Account for the total length of the pipes you will use to complete the hoops and the endwalls. Roll-up sides will require an extra 4′ of plastic.

If you are measuring plastic for the double layer, you will only need enough plastic to cover from hip board to hip board as the second layer will only need to cover the top of the structure.