Building A Hoop Greenhouse: Plastic Requirements And Costs

When building a hoop greenhouse, it is important to consider the type and amount of plastic cover to use. The size of the plastic cover depends on the width and length of the structure, including any excess required to ensure complete coverage. Various methods can be used to calculate the required size, and it is recommended to choose a plastic cover that is slightly larger than the structure to avoid any shortages. The type of plastic used is also crucial, with factors such as light transmission, diffused light percentage, durability, and expected lifespan influencing the decision. Some common types of plastic include contractor plastic sheeting, UV-treated polycarbonate panels, and greenhouse poly.

Calculating the amount of plastic needed

Step 1: Measure the Width

Start by measuring the width of your hoop greenhouse. This can be done by throwing a rope over the greenhouse, bringing it down to ground level on one side, and marking the rope. Then, stretch the rope straight and measure the distance to the mark. This will give you the accurate width, or arch's radius, of your greenhouse. It is important to add a buffer of 4 feet to the measured width to account for safety and/or roll-up sidewalls.

Step 2: Measure the Length

To determine the total length, you need to measure the height of your greenhouse from the ground to the highest point of the hoop and double that value. Then, add this value to the length of your structure. This will give you the total length required for the plastic.

Step 3: Account for Excess Material

It is crucial to have some excess material at each end of your plastic covering. This extra material ensures that you don't fall short and provides flexibility during installation. A good rule of thumb is to add at least 8 feet to the total length to account for this excess.

Step 4: Choose the Right Plastic

When selecting the plastic for your hoop greenhouse, consider factors such as light transmission, diffused light percentage, and anti-drip properties. Additionally, look for UV-treated plastic to protect your plants and structure from deterioration. Thicker plastics, like 8 mm Twin Wall Polycarbonate, offer more durability and are harder to puncture or tear.

Step 5: Determine the Number of Pieces

Decide if you want to cover your hoop greenhouse with one piece of plastic or separate pieces for the end walls and top cover. Using one piece of plastic for everything may be more efficient, but using separate pieces can help reduce plastic waste.

By following these steps and calculations, you can determine the amount of plastic needed for your hoop greenhouse, ensuring a successful covering that provides the necessary protection for your plants.

Choosing the right type of plastic

When choosing the right type of plastic for your hoop greenhouse, there are several factors to consider. The plastic you select will impact plant quality and growth, as well as the amount of time you spend installing and replacing it. Here are some key considerations to help you make the right choice:

Light Transmission and Diffused Light

The amount of light that can pass through the plastic is an important factor. Clear plastic allows the most light, making it a popular choice for gardeners, especially in early spring or late fall when sunlight is limited. Opaque plastic filters light, reducing it by about 45%, which can be beneficial in warm climates or during summer to prevent overheating plants. White plastic is also available, but it filters light by 55%, so it is not commonly used.

Thickness and Durability

The thickness of the plastic will impact its durability, light transmission, and insulation properties. Most greenhouse applications recommend a thickness of at least 6 mil, which offers a balance between strength, longevity, and light transmission. Thicker options, like 8 mil and 10 mil, provide even more strength and durability, but with a slight decrease in light transmission. On the other hand, thinner options, like 4 mil, are not very durable and may not last long.

Woven vs. Regular Plastic

Woven plastic, made from thin strips of polyethylene plastic in a grid pattern, offers significantly more strength and puncture resistance than regular plastic. It is ideal for areas with frequent thunderstorms and hail. Woven plastic also has the added benefit of UV protection, which helps prevent degradation. However, regular plastic, like polyethylene, is more readily available and cheaper, although it may not last as long.

Manufacturer's Warranty and Lifespan

The expected lifespan of the plastic is an important consideration. While manufacturers provide warranties, often for 4 years, many plastics can last years beyond this, depending on factors like location, care, and environment. Polycarbonate, for example, is known to last up to 10 years.

Anti-Drip Properties

Some greenhouse plastics have anti-drip properties, which can reduce the amount of internal dripping onto plants.

By considering these factors and comparing the technical specifications of different plastics, you can choose the right type of plastic for your hoop greenhouse, ensuring optimal plant growth and a suitable lifespan for your structure.

Comparing different types of plastic

When choosing the type of plastic for your hoop greenhouse, you should consider the following factors: technical specifications, durability, expected lifespan, price, and availability. Here is a comparison of different types of plastic based on these factors:

Polyethylene Plastic

Polyethylene plastic is an inexpensive, versatile, and easy-to-use option for hoop greenhouses. It offers many of the same benefits as traditional greenhouse panels at a lower cost. With proper care, polyethylene plastic can be long-lasting due to its strength and improved UV protection. It provides up to 90% light transmission and comes in two grades: greenhouse grade and utility grade. The utility grade is more readily available but may not last more than a year or two. On the other hand, the greenhouse grade offers higher quality and includes UV protection, prolonging its lifespan.

Woven Plastic

Woven plastic is a variation of polyethylene plastic that features thin strips of the material arranged in a grid pattern. This type of plastic is 15 times stronger than regular polyethylene plastic. It is a great option for hoop structures that require a flexible covering and can withstand extreme weather conditions such as heavy snow or high winds. However, it is more expensive than the utility grade of polyethylene plastic.

Polycarbonate

Polycarbonate is a rigid and more expensive option compared to polyethylene plastic. It offers excellent light transmission, with up to 10 years of lifespan. It is shatter-proof and much lighter than glass, making it ideal for permanent structures that need to be covered all year round.

Anti-Drip Greenhouse Plastic

This type of plastic is designed to reduce internal dripping onto plants. It is an excellent choice if you want to minimize the impact of dripping on your plants.

In conclusion, the type of plastic you choose will depend on your specific requirements, such as plant needs, weather conditions, budget, and the desired lifespan of the greenhouse plastic.

The durability of different plastics

When it comes to building a hoop greenhouse, one of the most important considerations is the type of plastic you will use. Different plastics have different properties, and choosing the right one will ensure your greenhouse is durable and long-lasting.

One of the most common plastics used in construction is polyethylene terephthalate (PET). PET is the fourth-most produced synthetic plastic and is known for its excellent chemical resistance to organic materials and water. It is also highly durable, with a high strength-to-weight ratio, and is easily recyclable. This makes it a good choice for a greenhouse as it can withstand the elements while also being environmentally friendly.

Another option is polyvinyl chloride (PVC), which is the third-most produced synthetic plastic polymer. PVC can be manufactured to be either rigid or flexible, making it a versatile option for construction. It is often used in doors, windows, and bottles, but its flexibility also makes it suitable for plumbing products and electrical cable insulation. However, one downside of PVC is that it is not as easily recyclable as PET and can be more difficult to dispose of properly.

For a more flexible option, polypropylene (PP) is a thermoplastic polymer that is known for its strength and flexibility. It will not crack under repeated stress, making it a durable choice for a greenhouse that may need to withstand high winds or snow loads. PP is also heat resistant and acid resistant, further adding to its durability.

Finally, acrylic is a transparent thermoplastic that is often used as a lightweight, shatter-resistant alternative to glass. Acrylic can be made in a variety of colours and finishes, including fluorescent, abrasion-resistant, and UV-tolerant, making it a versatile option for a greenhouse. It is also worth noting that some plastics, such as polystyrene, are not ideal for greenhouses as they are highly inflammable and can leach harmful chemicals when heated.

In summary, when choosing the right plastic for your hoop greenhouse, consider the specific properties that will make your structure durable and long-lasting. Factors such as strength, flexibility, heat resistance, and recyclability should all be taken into account to ensure your greenhouse can withstand the test of time.

The lifespan of different plastics

When building a hoop greenhouse, it is important to calculate the amount of plastic required to cover the structure. The end walls and the top section of a hoop greenhouse need to be covered in greenhouse film. The width and length of the material needs to be determined to calculate the size of the cover.

Now, the lifespan of the plastic used in hoop greenhouses varies depending on the type of plastic. Plastic is designed to last, and nearly all plastic ever created still exists in some form today. The lifespan of different plastics varies from 200 to 1000 years or more. For example, plastic straws can take up to 200 years to decompose, while plastic bags can take up to 1000 years. The plastic in coffee pods and toothbrushes can take even longer, up to 500 years or more.

The longevity of plastic poses significant problems for human health and the environment. As plastic degrades, it fragments into microplastics that can enter the food chain and have endocrine-disrupting effects on humans. Plastic waste also affects marine life, with plastic bags being one of the greatest impacts on ocean wildlife. The burning of plastics to avoid ocean pollution creates new issues, such as toxic air emissions and wastewater.

While there is currently no global solution to address the toxic life cycle of plastics, some alternatives are being explored, such as reusable and edible packaging. Reducing plastic consumption is crucial for protecting the planet and wildlife.

Frequently asked questions