Installing Greenhouse Plastic

WHAT PLASTIC IS BEST FOR A GREENHOUSE?

Polyethylene plastic is a popular cover option for greenhouse structures. It is an excellent option for farmers looking to use a structure for season extension. Good-quality polyethylene greenhouse plastic should last you at least four years, even in high UV environments, when installed properly

When selecting a plastic greenhouse covering, look for a thickness of at least 6 mil. The polyethylene film should also have a UV stabilizer built-in.

Please do yourself a favor and don't buy cheap polyethylene film from the big box stores. These plastics lack UV stabilizers and will quickly begin to break down from sun exposure. The plastic shreds and flakes create a huge mess that will need to head to a landfill after one season.

Determine the Size of Greenhouse Plastic Needed

The size of your greenhouse film can be determined by measuring the length and width of the growing structure. 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.

How to Install Greenhouse Plastic


Installing greenhouse film over your hoop house for the first time is where most of the questions come from when people contact our tech line at Bootstrap Farmer. We can honestly say that no one has ever called to tell us it was harder than they first believed it would be.

We recommend starting the project with a team of 3-4 people. Limited experience is required to help install the greenhouse plastic.

Keeping a good level head and only working with the piece in front of you, focusing on one foot at a time, is all you can do. You’ll find that once you get going, you really don’t have a chance to stop. When you work in the proper order, it all comes together on its own.

It is a good idea to have a couple of pieces of wood or paint roller handles on the inside of the structure to help nudge the plastic over the top of the hoops. Keep a step ladder ready for the endwall that you will start on first. Some people like to tape cross connectors, hoop seams, and hardware to prevent any premature wearing out of the plastic. Duct tape works well for this. For an even tighter wrap, we recommend using electrical tape for this step.

Begin by unfolding or unrolling your plastic lengthwise along the hoop house. You will know which side faces down (the anti-condensate side) as you will be able to read the labels from the inside of the hoop house

Covering a hoop house is best done in the morning when winds haven’t picked up yet. It’s easier to start on the side working into a prevailing wind.

As you begin lifting the plastic over the hoops, the breeze will help to open up the plastic. If you work against the wind, the plastic will be pushed onto the ribs making the job way more difficult than it needs to be.

Ideally, two people will each grab a corner of the plastic on the ends and begin lifting over the hoops. This plastic can take significant tugs, so do not be afraid to pull when needed. Be mindful of snagging on corners, boards, or hardware. This will cause rips.

If you have other helpers, you can position them on the endwalls on the side of the film where it is unrolling from and help unroll/fold to give the pullers slack.

The plastic, when fully rolled out, will drape down on both sides and down both endwalls with at least 2’ all around the ground.

Begin at the top of an endwall and work down one side to the ground and then top to bottom again on the other side. Then move your ladder to the opposite endwall. With help, pull the plastic as tight as you can toward you and begin securing the film into the channel top to bottom and side to side.

Next, move to one of the long sides and begin securing the film into the lock channel with spring wire at the hip board. Once the plastic is secure along the length of one side, move to the opposite long side. While pulling down as tight as you can, secure the plastic with spring wire. After completion, you will be able to see where you can retighten the plastic by removing a section of spring wire and pulling from the bottom.

Once you are happy with the top, you can move onto the rollup side's installation or if foregoing the rollups, secure plastic to the baseboards.

A lot of folks ask us why the baseboard needs lock channel and spring wire if you are using roll-up sides.

For one, it gives you the option to fully seal off your roll-up sides with spring wire during a significant storm event or the winter. Second, it gives you options to secure insect netting.

Note: Insect netting needs to be installed before plastic goes on. Remember, more than one layer can fit into a lock channel.

Installing Greenhouse Plastic with Rollup Sides

For roll-up sides, you will wrap at least 1’ of greenhouse film around ¾ EMT down the length of the greenhouse. Feel free to cut off any excess from the bottom past 12”. Once the plastic is secured to the crank end, you may find that hand-rolling the non-crank end as you roll the sides up and down assists in alignment. Once you are satisfied with that, roll the side walls down to the baseboard to begin trimming for the end wall.

Check out this post for details on how to cover your endwalls.

Why do we use spring wire?

All the reasons to use Lock Channel and Spring Wire

Wondering if you need a second layer?

Check out all the info on Double Layer Inflatable Plastic