Polycarbonate Greenhouse Glazing
Polycarbonate greenhouse glazing is today, the most commonly used covering material for greenhouses, having surpassed glass for that a purpose. As a material “Poly” as it is sometimes called, is a solid plastic material.
Polycarbonate does a great job when it comes to diffusing sunlight, insulating against heat loss and is known for being very durable. Newer poly panels come with special coatings to protect against degradation due to UV rays. For cost effective installations, some may choose the cheaper single layer panels. If you’re tempted to save cost in this area, be sure to consider your climate and future heating costs.
More often than not hobby greenhouses will utilize double walled poly glazing. Beyond being double or triple paned, a greenhouse designer will also have the choice of choosing the thickness of their glazing. This thickness will differ depending on your climate and greenhouse needs. When ordering, you will normally have the choice of poly ranging from 4 to 10 millimeters. When considering this purchase you should know that the thicker the material the higher the insulation value (commonly called the R-value). In our conversation with some greenhouse kit providers, they told us that the best “bang for your buck” comes from going from 4 to 6 millimeters. There is less of an efficiency increase if going from 8 to 10 millimeters.
Although twin walled polycarbonate is the industry standard, you should know that you still get what you pay for. Look for reviews from previous customers before ordering to avoid purchasing low quality coverings.
Advantages of Polycarbonate Greenhouse Glazing
- Polycarbonate glazing is light, strong and shatter resistant.
- When layered it retains heat better than glass.
- Corrugated poly offers excellent light transmission – better than glass even!
- It’s long lasting, up to 15 years in some cases. Though manufactures will let you know what you can expect for longevity.
- Unlike glass, it transmits diffused lights, which helps in avoiding burning of the plants.
Disadvantages of Polycarbonate Greenhouse Glazing
- Polycarbonate can scratch easily which may be unsightly and could lead to less efficient light transmission.
- Double and triple walled panels can reduce light transmission – which will affect the growing of your plants.
- Single panel coverings are offers poor heat retention.
- Like other plastic coverings, polycarbonate can be susceptible to condensation – though this concern can be addressed with special coverings.
- Like glass it can be costly. The cost can increase if you purchase the double or triple paneled options.
- Corrugated polycarbonate paneling does a poor job at retaining heat.
As you can see, choosing polycarbonate greenhouse glazing for your greenhouse is a smart choice. No material is perfect, by “poly” should be near the top of everyone’s list.