Comparison of Greenhouse Glazing Properties

Greenhouse glazing comes in many different types, with each material having its own benefits and disadvantages. We’ve covered these materials in several different posts here on our site. If you have a question regarding a particular type of glazing, please take some time to review those earlier posts.

For this posting we wanted to put together a simple chart showing different types of glazing materials and their characteristics and capabilities. There are a lot of great resources out there for anyone looking to build their own greenhouse (and we hope you consider this website one of those). This chart comes from one of our favorite resources; Otho’s All About Greenhouses. We’ll post a link at the bottom of this posting if you’re interested in purchasing – if you’re dreaming about building your greenhouse it is a great place to start.

For the chart below you will see four basic columns;

  • Glazing Material – Simply, this column lists the greenhouse glazing material that is being reviewed. It is not a complete listing of all types or configurations, but more a short-listing of what we felt was an accurate showing of the most common types.
  • Visible Light Transmission – As discussed many times here at the DIY Greenhouse, the amount of light that is able to pass through glazing material has a direct impact on the growth of your plants inside the greenhouse. The percentage shown is an approximation of the amount of visible light that is able to pass through the listed glazing material.
  • Heat Loss – Heat is an important component to a greenhouse, and it can also be one of the most costly if you are trying to grow plants in colder climates. Unlike our homes, which we’re able to insulate walls and roofs, a greenhouse’s walls are made up of only the glazing material chosen. But like insulation, each glazing material has it’s own R-value – that is the level of efficiency at which it resists heat leaving the structure. Within the column, if something is listed as “Above Average” heat loss this means that the material has POOR heat retention characteristics.
  • Estimated Lifespan – This column shows how long one might expect the glazing material to last if properly cared for.

Overview of Greenhouse Glazing Materials

Greenhouse Glazing Material

Visible Light Transmission

Heat Loss

Estimated Lifespan

Single Pane, Clear, Tempered


Above Average 25 +  Years
Double Pane, Clear, Tempered


Average 25 +  Years
Double Pane, Clear, Tempered, low-E


Below Average 25 +  Years
Double Pane, Ckear, Tempered, Heat Mirror


Below Average 25 +  Years
Double Pane, Bronze Tint, Heat Mirror


Below Average 25 +  Years
Rigid Plastic
Single Layer Polycarbonate, Clear


Above Average 10 +  Years
Single Layer Fiberglass, Clear


Above Average 10 +  Years
Double Layer Acrylic, Clear


Average 20 +  Years
Double Layer Polycarbonate, Clear


Average 15 +  Years
Triple Layer Polycarbonate, Clear


Above Average 15 +  Years
Plastic Film
Single Film, Clear, Greenhouse Grade


Above Average 4 Years
Single Film, Clear, Agricultural Grade


Above Average 9 months
Double Film, Clear, Greenhouse Grade


Average 4 Years
* Taken from Ortho’s “All About Greenhouses”

As promised, please click the link below to purchase “Ortho’s All About Greenhouses”. NOTE: This is an affiliate link and we will receive a small % of the sale which will help us keep this website running.

All About Greenhouses (Ortho’s All about)

Choosing the correct greenhouse glazing material for your greenhouse is one of the most important choices you will make before you are able enjoy your greenhouse. We hope that this chart aids in you being able to make an informed choice.

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