Greenhouse plastic such as polyethylene greenhouse film is designed to be resistant to ultraviolet rays and to last for up to 14 years. These plastic pieces are designed to fit easily over hoop houses and other arched greenhouses. The steps for installing greenhouse plastic will vary depending on the style of plastic that you use and the way in which is packaged. Some greenhouse plastics come folded in accordion, W- or Y-shaped folds and can be unfolded to a width that will cover an entire greenhouse. Other rolls may require that you cover your greenhouse in sections.
Unroll a 1-foot section of greenhouse plastic to determine the way in which the plastic was folded and attached to the roll.
Carry greenhouse plastic rolls that have been folded in an accordion, "W" or "Y" shapes to the top of your greenhouse.
Unroll greenhouse plastic down the length of the greenhouse roof at the very top of the greenhouse.
Unfold the greenhouse plastic sheeting so the sides of the plastic drape over the top of the greenhouse and reach to the ground.
Attach the loose sides of the greenhouse sheeting to the bottom of the greenhouse frame. If your greenhouse frame is made of wood, you can staple the plastic to the frame with carpenter’s staples. You can also attach a prefabricated locking channel that attaches to the frame and locks the plastic in place.
Unfolded Plastic Rolls
Unroll the unfolded plastic on the ground next to the greenhouse. Take care not to puncture the plastic as it lies on the ground.
Tie a length of rope to each corner of the plastic on one side. Throw the rope across the roof of the greenhouse and allow it to dangle to the ground on the other side.
Pull the rope from the other side of the greenhouse to hoist one side of the plastic over the top of the greenhouse and down to the other side. This will drape the plastic over the roof of the greenhouse like a large blanket.
Short Plastic Rolls
Measure the width of the greenhouse with a measuring tape from the ground on one side to the ground on the other side.
Cut a length of short-width greenhouse plastic so it is the same measurement long-ways as the width of the greenhouse.
Roll this length of plastic up and carry the new roll up to the rafters of the greenhouse. Lay the roll so one end overlaps the greenhouse end by 6 inches. Unroll the plastic roll halfway so that the end of the roll touches the ground. Then allow the other end of the roll to fall to the ground on the other side of the greenhouse.
Cut another length of greenhouse plastic and carry it up to the rafters of the greenhouse. Place this plastic so it overlaps the first plastic section by 6 inches. Continue to place the roof on the greenhouse in sections.
Attach each section at the base of the greenhouse using carpenter’s staples or prefabricated greenhouse channels.
Seal the seams of the greenhouse where the sections meet using greenhouse tape.