Greenhouses offer great value for any gardener hoping to extend their growing season. Instead of relying solely on what Mother Nature is in the mood to provide, a greenhouse provides shelter, temperature control, and easy, organized access to plants. While there are numerous forms a functional greenhouse can take, when adding a greenhouse to your garden, there are many factors to consider. For example, you will need to think about the space in your yard, the type of landscaping you have, humidity, rainfall, snowfall, temperatures, and the amount of sunlight your area gets. Heating and cooling costs are another detail to be wary of, taking into account that extra unused space at the top of some designs. Take a look at this list of greenhouse styles and peruse the pros and cons of each when making your decision about what will work best for you.
Hoop houses come in many styles, but their most common factor is the bent tubing that forms an arch to create the structure. The ends of the tubing are hammered into the ground for stability, with the curved tubes resembling half hoops, before a plastic or film is attached to complete the house.
Since hoop houses usually don't require large foundations to be erected, they're immediately less labor intensive than more complex greenhouse structures some of which may even require building a permit. In some areas a building with a foundation is also added to the property appraisal which results in more taxes. Hoop houses don't come with any of these complications and are relatively inexpensive to build. They also offer a lot of flexibility in sizing because you can easily add a new section, making the structure longer. From a growing perspective, this style also offers excellent lighting for crops placed inside.
The materials for hoop houses are typically lower quality than some other products so you can expect to replace the film about every four years. Because their insulation factor is not very high with only the thin plastic film to trap warmth, your heating costs will run higher as well. You may also need to pay for the electricity to run a blower in order to keep the film inflated. Severe weather or the weight of snow can easily damage this type of greenhouse.
Gothic Arch Hoop House
The Gothic Arch is a variation of the hoop house design that brings the hoop to a peak in the front of the structure. This change provide a sturdier frame, a steeper roofline, and allows snow to slide off the top of the structure. Be aware though, that the weight of the snow on the side of the Gothic Arch can cause damage to the materials so you will still need to shovel away any snow accumulations.
One option for any type of hoop house is to add a support beam from the ground to the center of the roof. Additionally you can add a horizontal crossbar or provide stellar weight management with full trusses.
When you picture a greenhouse, you probably envision the traditional cloudy, tarped cabin shaped structure seen in most magazines and websites. This form of greenhouse is popular for a reason, they're very effective, but there are still some drawbacks.
The trusses offer excellent support for heavy snow and the angle of the roofline allows for easy snow removal. The traditional greenhouse also offers excellent lighting and it is a durable, long term option. The design offers flexibility for adding vents or even glass windows when looking at options for airflow. Scalability is another advantage of the traditional greenhouse because it is easy to connect several houses together for larger operations.
Even with an efficient design, the traditional greenhouse is still expensive to heat. The initial construction costs are higher too. Most traditional greenhouses require a foundation, which could result in the need for a building permit and will likely result in higher property taxes.
The dome style greenhouse that you may have seen is appealing as well as functional.
The outstanding strength of the geodesic dome allows for worry free winters in heavy snowfall areas. In addition to being able to tolerate the weight, snow removal is also easy due to the angle of the roof. This design also allows for efficient cooling vents and good lighting.
The geodesic dome is moderately expensive to erect. The main disadvantage to the shape is that the odd angles along the walls affect the layout of your beds and limits headroom so it is not the most efficient use of space. You may also need a foundation and building permit in addition to payment of higher taxes.
The walipini greenhouse is alternately called a pit greenhouse because it is built underground, framed in with cement walls.
The underground position of the greenhouse makes use of natural cooling, which is a cost saver during the hot summer months. This is a better option in southern states where snow is infrequent and heats can be extreme.
A building permit may be required. The pit greenhouse receives poor natural light in the morning and the evening. Since the roofline is at ground level it is easy for dogs, livestock, or humans to walk on and damage the roof or even fall into the greenhouse.
Passive Solar House or Lean-to Greenhouse
This type of greenhouse attaches directly to the side of the house, shed, barn, or other structure.
Provides extremely good energy efficiency because the north wall is adjacent to a heated source. Since the roofline is a lean-to style, the snow slides off easily. It is a good design for the hobby greenhouse user.
May need a building permit and be considered additional square footage for taxes. Because it is not free standing, it will likely only receive midday sun. Passive solar houses are difficult to add on to so this design is not good for larger operations. These greenhouses often use barrels of water stacked in the corner to collect heat during the day and release it during cooler nights. In an already smaller space, the barrels take up valuable floor space.
The Chinese greenhouse is a less-commonly used design. The Chinese passive solar greenhouse generally has three walls of brick or clay that make up the north, east, and west sides of the structure. Only the south side of the building consists of transparent material (usually plastic film) through which the sun can shine. During the day, the greenhouse captures energy from the sun in the thermal mass of the walls, which is then released as heat at night. The walls also help block the cold, north winds, which would otherwise speed up heat loss. At sunset, an insulating sheet typically made from straw, pressed grass, or canvas, can be rolled out over the plastic to further slow heat loss. These features keep the indoor temperature of a Chinese passive solar greenhouse up to 45 degrees higher than the outdoor temperature.
It offers fairly good cooling with southern exposure. It is less expensive than other options. A nice design for small greenhouses.
The Chinese greenhouse blocks morning and evening sun. The design doesn’t scale for larger operations without adding additional supports. You may need a foundation and permits.
The windowfarm may not technically be considered a greenhouse although it does take advantage of solar heat through a window. This setup uses a series of hydroponic plants dangling from chains in a kitchen, living room, or office.
Good for small production of herbs or leafy greens. You can set up a self watering system. Provides easy access to crops.
Limited production. May not be the look you are going for in your living space.
Deciding which type of greenhouse best suits your needs takes some serious consideration. While cost and the available area in your yard are major factors, also think about things like whether early morning sun is a requirement to dry the dew off your plants and if you plan to increase the size of your greenhouse down the road. Evaluating your needs to install the greenhouse that works best for you will provide cost savings, higher crop production, and a more enjoyable experience for you.