2019 Best Greenhouse Plastic Options
What is "the best" greenhouse plastic for your greenhouse? There are many types of greenhouse plastic from which to choose. The key is defining your budget, understanding your environmental conditions and your objectives, and learning about your options.
6 mil Plastic/Poly Sheeting
In the 1960's 6 mil polyethylene sheeting emerged on the scene for hoop house style greenhouses. Back then and even today its greatest asset is its price. 6 mil plastic is economical. By the time 1970 arrived UV inhibitors were added to give the plastic a longer life span. 6 mil plastic could survive the sun for up to 3 years. Fifty eight years later 6 mil poly is still used by the budget conscious grower. This film will get you by. The downside to 6 mil is bad weather (wind, snow load, hail), and strong sun. A bad storm can damage the cover and recovering might be necessary. Additionally your crop may be damaged or ruined. In summary, 6 mil poly will get you by for potentially four years, save you money for its purchase, but require your labor and time to recover every 3-4 years or sooner if it tears.
Twin wall polycarbonate
Twin-wall plastic also called, Twin-wall polycarbonate is an extruded polymer product. It is impact resistant, has some thermally insulative properties, is attractive, and will not yellow. It is fairly easy to install. The down side is how easily damaged it can get from wind, storms, and blizzards. Additionally it is prone to attracting dust and dirt which may reduce the amount of light entering the greenhouse. It is important to clean polycarbonate to abate algae on the inside and outside of the greenhouse. Condensation can be a problem when it becomes trapped between the layers. It is more expensive than 6 mil poly, but not as expensive as glass.
There is nothing more beautiful than a glass greenhouse when the class is sparkling clean. Glass greenhouses offer great light transmission. longevity and is traditional but it lacks thermal efficiency and may burn some plants. Glass greenhouses are great unless the glass is broken from hail or some other object. Then the mess and cost to replace it is less than optimal! The good news for glass is how long it will last under proper weather conditions. Installing glass is labor-intensive due to how heavy it is, and how difficult it is to handle. Depending of you are looking for pure functionality, glass may not be the best bet.
Reinforced polyethylene film is stronger than 6 mil greenhouse plastic due to the inner layer of cord that is sandwiched between the layers of plastic. It stands up to wind, is puncture proof and tear resistant but only lasts 4 years (due to the sun's UV rays) in most cases and manufactures (as of this writing) are not offering a full guarantee. Delamination has been reported as a problem as well.
Please click here for all the attributes that have growers coming on board. (Yes the film with the bubbles!)The downside to SolaWrap is the cost of the film. When you factor in your labor, and the fact that you may never have to recover your house again- and then ask your self if the cost of the film is really a factor. Once you make the initial investment, chances are strong you will not be calling again for more film. In the event you do have a failure, you will only be replacing that strip of SolaWrap, not the whole structure. Of course if you greenhouse collapses due to a weather event, then sadly you will be recovering your NEW greenhouse!
Polyvinyl Plastic- Not uses so much any more, but this plastic is a little stronger than 6 mil plastic but after 3 years it will turn brittle and break
Fiberglass- fiberglass is not used as much as it once was...
How do you define"Best Greenhouse Film" Which do you think is best?
- Price? If a low cost film is what your are looking for, then 6 mil plastic films will be the "best" greenhouse film due to its relatively low initial What you save in the initial film investment you will lose in labor cost. 6 mil greenhouse film will not last very long, and may not come with much is any of a guarantee. You will be replacing that film due to aging from the sun, or a storm ripping a hole in the film.
- Energy Considerations: The price of heating and cooling your greenhouse is the second biggest expense beside the labor of building and covering your greenhouse. Which covering offers the best heating and cooling R-value?
- UV Lifespan: For the plastic films, how much do you value having a UV guarantee. Solawrap offers a 10 year full warranty. Do other plastic films offer this warranty? The big secret is...SolaWrap has been going strong in Europe on the same houses for over 30 years!
- Brute strength: What is the best greenhouse covering when it comes to wind, hail and snow load? If this is important to you compare Solawrap to the others. We think you will find it to be the best across many of these categories.
- Labor for replacing the coverings: Should your greenhouse covering be damaged by a bad storm or damage to the covering- which greenhouse covering is the best in offering you a cost saving to do a repair? Most greenhouse films will require you to recover the entire structure. SolaWrap is built in strips, so in the unlikely event there is damage to the cover, you will only be replacing a 4', 5', or 6" section- not the whole structure.
Bottom line is that there are the above considerations and more when deciding on selecting a greenhouse covering for your structure.