Which Greenhouse Glazing Material Do I Use?

For decades glass has been the traditional greenhouse glazing material. However, the trend of using plastic everywhere did touch the gardening field and the greenhouse glazing particularly.

You can find lots of options on the market starting from polyethylene films and finishing with the fiberglass panels.

In this post I am going to guide you through the entire range of available options and highlight the pros and cons of each material.

Hopefully, you will pick the right greenhouse glazing material!

Let’s look at the summery of the most popular covering materials:

Glass – a pioneer of the greenhouse glazing;

Polycarbonate – a durable option used to replace a glass;

Plastic Film – a cheap and easy to set up for a small greenhouse;

Fiberglass – a lightweight and strong plastic;

Acrylic – a clear plastic imitating glass;

Solexx – an innovation in the greenhouse glazing;

Okay, now with the lots of options you might be a little bit confused which one is the best for YOUR greenhouse?

The first glazing material which I would consider getting is glass.

Glass Greenhouse Glazing

I have talked a lot about the glass greenhouse glazing in the What is the best glass glazing for a greenhouse?article. So, here I am going to quickly discuss the pros and cons of using a glass glazing.

As you might know it’s a traditional material used for decades (mostly because it was the only one option available). It is heavier than plastic which is harder to install but it is aesthetically more pleasant.

The main issue I have with glass is that it can break into long sharp strands. Of course, you can get a stronger option like tempered or laminated glass which is going to be more pricey.

With an appropriate care glass is going to last for a long time and won’t discolor as plastic will.

Also, glass requires a strong frame structure made from wood or aluminum. To find more details on the frame materials check out this article.

Glass is a very good option for a cold frame greenhouse and it will look fabulous in your backyard.

There is a variety of plastics which you can use to cover your greenhouse and I am going to help you choose one!

Let’s start with the polycarbonate.

Polycarbonate Greenhouse Glazing

Polycarbonate doesn’t experience problems with shattering and condensation in comparison to glass glazing.

The insulation ability of the polycarbonate cover is really high and helps to maintain the temperature inside the greenhouse at the same level.

This is very beneficial during the winter season as you will keep the energy use as low as possible to heat your greenhouse. Moreover, it filters out the harmful UV lights which can damage your plants.

Okay, now let’s look at the structure of polycarbonate. The surface of the material is corrugated which is good at refracting daylight creating the perfect growing conditions.

All the plastics are going to be lighter than a glass and polycarbonate is not an exception. In addition, it is very strong and doesn’t easily break so makes the transportation and working with the material hassle-free.

One of the disadvantages of using polycarbonate and plastics in general in comparison to glass is the warranty. The lifespan of any greenhouse plastic is maximum 10 years when the glass can last for over 30.

Also, the polycarbonate can be easily scratched or can be popped out of the frame.

Plastic Film Greenhouse

If you are looking for a cheaper covering material you have a choice of two plastic films: PVC also known as polyvinyl chloride or just a vinyl and polyethylene film.

You have to take a good care of the plastic film by cleaning it regularly. When choosing a plastic film pay attention to the utility grade as it shows how it can be exposed to the sunlight.

For example, some of them can be used for two seasons. It should also be UV treated as plastic can rod because of the harmful UV radiation.

Then, look at the thermal protection as it is very important for a plastic to reflect the heat back into the greenhouse.

Lastly, the plastic should be capable of the anti condensation because water accumulating on the film can minimize the sunlight and can fall onto plants and damage them.

Fiberglass Greenhouse

Fiberglass is a clear or translucent lightweight but strong plastic. It can’t be broken by hails during the storm as glass can but conducts as much light as glass.

Also, in comparison to other plastic fiberglass has the longest lifespan which start from 10 years manufacturers guarantee.

With time the fiberglass panels can get worn down on the top leading to the exposure of the fibers that can catch dirt. As a result, sunlight doesn’t pass through. To fix it you need to wash off the dirt and reseal the breakage.

Another problem with fiberglass is that it is prone to breakage from the UV light. To avoid this you need to apply a new coat of resin every 5 or 10 years (depends on the grade of fiberglass).

Acrylic Greenhouse Glazing

Acrylic glazing is very similar to glass. It is clear and almost as durable. The greenhouse glazed with acrylic panels is guaranteed to withstand snow load, winds and hail.

This explains why it’s heavier than other plastics but still is very easy to work with.

The panels are quite flexible to be put on the greenhouse frame. There are two types of acrylic used for greenhouses: extruded and cell cast.

The difference is in the manufacturing process. The extruded is manufactured through a cheaper process resulting in a softer material which is prone to being scratched.

On the other hand, the cell cast type is of a higher grade and is more expensive but won’t be easily scratched and will withstand cruel weather conditions.

Solexx Greenhouse Glazing

Solexx is characterized as a plastic of the superior quality. It is a double wall plastic which is much cheaper than polycarbonate.

The material is light and flexible making it easy to set up. I haven’t used Solexx material yet, so if you have tried it for a greenhouse, please let me know in the comments section below.

I hope you have found everything you were looking for regarding the best greenhouse glazing material in this article.

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