Condensation has negative effects that can lead to a reduction in crop yield and ultimately, profit. For example, condensation produces water droplets that reflect incoming light. This reduces the light reaching the plants and leads to reduced crop growth. Condensation also creates droplets that drip onto plants causing mildew, disease and ultimately, yield loss.
Follow these four expert tips from David, our ACRYLITE® greenhouse expert, to prevent condensation issues in your greenhouse.
1. Prevent moist air by sealing the chambers
Prevent moist air (which is less dense and naturally rises) from flowing up into the multi-skin chambers by closing the open ends of the sheet. Here is a simple but very important rule: the multi-skin panels should be sealed as tightly as possible at the top and as tightly as necessary at the bottom. This means adhesive sealing tape at the top and an extruded aluminum closure at the bottom. (We do not recommend a breather tape at the bottom; there is too much risk of fouling.)
2. Drill weep holes for drainage
Drill weep holes in the bottom aluminum closure. Acrylic and polycarbonate polymers are permeable to water vapor, and over time humid greenhouse air will diffuse through the inner skin into the channels where it condenses. The weep holes allow this condensate to drain away.
3. Reduce droplet formation
To reduce droplet formation, choose a glazing product with water-dispersing condensation control. Our ACRYLITE® multi-skin acrylic products contain a NO DRIP coating which not only reduces droplet formation but significantly increases practical light transmission during greenhouse operation. This NO DRIP coating also prevents algae growth and eases cleaning.
Check out the National Greenhouse Manufacturers Association for more information.
4. Work with experienced greenhouse suppliers
Work with an experienced greenhouse manufacturer and equipment vendors to achieve optimum humidity control. Greenhouse ventilation design, growing methods, watering systems, and automatic controls all impact humidity and condensation. Experienced suppliers know the best solutions. When choosing a greenhouse glazing team, choose a reputable greenhouse designer and fabricator with a long history and deep knowledge to ensure proper installation.