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Greenhouse and Pond Liner Coverings and Films

By: Kalia Williams *

Pond liners are used in ponds to keep water from seeping into the soil. They work by forming an impermeable layer between the water and the soil which prevents water loss. Pond liners also provide a base for plants to root themselves in and provide a comfortable environment for fish to explore. Greenhouse coverings, although they serve a different purpose than pond liners, are also necessary to cultivate growth. A heavy-duty greenhouse cover is ideal for protecting investments from the unwanted light transmission and provides longterm service in high UV level environments.

Pond Liner Plastic Film Pond liners are typically made out of multiple sheets of liner material that are welded together. Leaks can occur anywhere where a seam joins two sheets. In order to avoid leaks, pond liners need to age well. The liner material must be resistant to UV rays and to weather. There are a variety of pond liner materials. The most common materials are EPDM, RPE, and PVC liners. Here are various liner material options:

RPE- Reinforced Polyethylene Pond Liners

Reinforced Polyethylene liners (RPE) are one of the most durable pond liners available. They can last up to 40 years and have excellent puncture resistance. RPE liners do not need a protective underlayment because of their higher strength. RPE can also be produced in large sizes because they are lightweight. RPE liners do not bend as easily as other flexible liners, which is one drawback of this type of liner.

Box Welded Polypropylene Liners

Box-welded polypropylene is one of the best materials to consider for regular or circular pond liners. Box welded polypropylene liners are durable and light. They are also UV resistant and safe for fish and plants. Boxwelding is a process that uses heat to weld liners to conform to various 3D shapes. Box welded polypropylene liners allow for covering ponds with corners that are seamless and without folds.

Rubber Liners

Rubber liners are heavy compared to other liner materials and they are not as puncture-resistant. Despite this, rubber liners are flexible and can fit nicely in ponds that have shelves and a variety of other features. Punctures or tears, leaks in seams, and age and deterioration are all factors that risk the chance that small rocks, tree roots, or other objects may remain in the hole excavated for the pond. The weight of the water pressing down on the liner may be heavy enough to puncture it. To decrease the chances of the liner tearing, strong liner material is necessary.

Greenhouse Coverings

Greenhouse covers are a key component in greenhouse construction. The ideal greenhouse covers are manufactured using a UV stabilizing additive to protect them from UV degradation and help them retain their original properties. The type of plant grown will determine the amount of light transmission needed and the type of material to be used. The size of the greenhouse will be determined by growing goals. A few factors that go into how to choose the right greenhouse include climate, budget, and what will be grown in the greenhouse.

Plastic Film Greenhouses

Plastic (polyethylene) film is a popular material to use for covering greenhouses. It has a low initial cost and requires limited structural materials and effectively diffuses sunlight. It is recommended to install a double layer of plastic film with airspace in between. This can reduce heating costs by up to 40 percent as opposed to other greenhouse cover materials.

Courtesy by Reef Industries

Polycarbonate Greenhouses

Polycarbonate is a more rigid plastic than polyethylene. Polycarbonate is flexible and its double-layered sheets are great for heat insulation. Due to its durability, polycarbonate sheeting is able to withstand hail storms and other accidents much better than glass. It is also not as prone to pollution damage or UV as polyethylene and can last up to 10 years. Polycarbonate sheeting does have a few disadvantages. It can be prone to yellowing or clouding, which results in loss of light over time. This material is also prone to algae growth.

Glass Greenhouses

Glass provides the best light transmission out of all of the various coverings, which makes it the ideal material for greenhouse glazing. It has a higher thermal rating compared to other coverings and can last a long time. They are also resistant to air pollution and UV radiation and they are non-combustible. A few disadvantages of glass coverings are that they are often susceptible to catastrophe and cracked panels have to be replaced quite often.

Fiberglass Greenhouses

Fiberglass is rigid and durable. Because of this, it does not need structural backing. Fiberglass holds up well to catastrophic weather damage. A few disadvantages of using fiberglass include its vulnerability to sun exposure. This material tends to swell and reduce light transmission when exposed to long periods of sunlight. Fiberglass may last for five years before the UV breakdown becomes a factor. Fiberglass is also quite combustible and flames will continue to ignite even if you remove it from the source of ignition.

Conclusion

Pond liner film and greenhouse coverings serve different purposes. Pond liners are used in ponds to keep water from seeping into the soil whereas, greenhouse coverings protect plants from various factors. Both of these materials are responsible for limiting UV degradation and providing a comfortable environment for fish or plants. Therefore, choosing the right material is a necessary step in the cultivation process.

*For further information, visit: www.reefindustries.com