Greenhouse Glazing Systems

Get to know the different glazing systems


We offer many options including single tempered glass, tempered insulated double glass, twinwall polycarbonate, and fivewall polycarbonate. For those customers wanting a living and growing space, we also offer tinted, high performance and laminated glass. We can help you choose the best balance between insulating value, aesthetics, and budget to suit your needs.

Things you should know:

  • Our continuous, exterior capping system secures the glazing and maintains an airtight seal – there are no gaps or clips. This greenhouse is designed to be weather resistant and energy efficient.
  • All glazing options can be intermixed in the same greenhouse
  • Our 3mm single tempered glass is offered with a 1/2″ overlap which is easier to ship and install.  A 6mm one piece of single tempered glass is an upgraded option for those who would prefer a clean look.

Check out our glazing options walkthrough

Which glazing system is right for you?

3MM Single Glass

Single glass makes for a nice show piece in your yard. Our single glass is tempered safety glass to minimize any possibility of breakage or injury. Glass appeals to gardeners who want full light transmission to control the amount of sun in the greenhouse.

Single Glass 3MM, Insulating R-Value .96 Approximately 95% light transmission.

6MM Single Glass

One solid sheet of tempered safety glass in every greenhouse bay which is double the thickness for even more strength and a beautiful seamless look.

Double Glass

Insulated double glass maintains superb heat insulation for all types of growing. Our double glass is tempered safety glass to minimize any possibility of breakage or injury.

Double Glass 16MM, Insulating R Value 2.1 Approximately 90% light transmission.

Optional high performance Low E glass (R Value) Heat Gain = 3.45. Approximately 70% light transmission.

Twinwall Polycarbonate

Our 6mm twinwall polycarbonate is the most economical. It is a practical choice for a working greenhouse as it offers 50% more insulation than single pane glass and diffuses harmful sunlight in the summer. It is essentially unbreakable, making it very safe in a family environment. The insulation will prevent the temperature in the greenhouse from changing drastically and results in the best possible growing environment.

Twinwall 6MM, Insulating R-Value 1.62. Approximately 82% light transmission.

Fivewall Polycarbonate

Our 16mm fivewall polycarbonate is the most energy efficient glazing available on the market today. It offers 50% more insulation than double glass and 80% more insulation than twinwall polycarbonate. Fivewall is ideal for colder climates and gardeners who grow specialty plants, or for those who wish to reduce long term heating costs. Fivewall 16MM, Insulating R Value 3.0. Approximately 62% light transmission.

The most natural and gentle way to cool your plants is with passive ventilation. Our greenhouses incorporate automatic ridge vents and optional side venting. Convection theory takes over as hot air rises out and cooler air is drawn through the lower openings.

For those with larger greenhouses or residing in hotter climates, it’s important to consider implementing a forced ventilation system to avoid overheating. A combination of exhaust fans and motorized intake shutters with thermostat are usually necessary for this. Keep in mind that this system will be relied upon for most of spring, summer, and fall, but don’t forget about your passive ventilation methods too! This will help reduce extreme temperature fluctuations and will be better for your plants. Just be cautious of occasional warmer winter days that could potentially damage your plants with a sudden flash of cold air.

Upgraded Glazing Options

6MM Laminated Glass

One solid sheet of laminated safety glass in every greenhouse bay. Similar to car windshields, this safety glass will not shatter and will remain intact even when broken. This glass type may be required for greenhouse roof’s where building codes require, common for applications over swimming pools, schools, and solariums. Available in single 6MM or Double Glass which is typically composed of an exterior tempered glass piece, an air gap with two layers of float/annealed 3mm glass and a laminated interlayer which blocks UV.

High Performance LOW-E

Maximizes the Insulating R-Value and reduces Relative Heat Gain to allow for a more comfortable space. The Low-E (low emissivity) coating on the inside of the glass reflects most UV and infrared while keeping a clear view through the glass. The Low-E coating also reflects infrared back towards the interior retaining more heat.

Read Our Complete Glazing Guide For More Information

Over 72 Years of Manufacturing the Strongest Greenhouses