Greenhouse Design

• With so many models on the market choosing the right kit for you can take a bit of time. Even the most inexpensive models on the market can offer you an environment conducive to growing year-round, so the ultimate choice is one that leans heavily on personal taste, climate and the space needed.
  Inexpensive kits often use steel tubing and plastic as building materials. These kits are quick to assemble, often requiring under an hour to put the frame together and attach the plastic cover to the walls and roof. The doors of these inexpensive units are usually made of zippers, and the entire greenhouse can be taken down and stored during the hot months of the year.
  For a more expensive, sturdier frame you can choose a kit that uses aluminum, steel or hardwood. There are even frameless models available that consist only of a strong fiberglass covering.
  The covering of your greenhouse is even more important than the frame. For cold climates you should look for a double-wall to provide adequate protection from the elements for your plants. Double-wall polycarbonate or acrylic plastic are commonly used materials available in kits. For warmer climates, a single-wall fiberglass kit can be used.
  
  

Heating

• Even in warmer climes you may need to provide additional heat for your greenhouse on colder days. A greenhouse attached to your home can be easily heated at times just by opening a connecting door or window. This heat exchange works both ways, as an attached greenhouse can help to heat your home during fall and spring months.
  For an unconnected greenhouse, purchase a separate greenhouse heater. These small heaters, available in electric, gas or propane models, will emit carbon dioxide unless vented to the outside. While this can be a safety issue for gardeners, it can be good for the plants. But for safety's sake it's best to allow the plants to miss out.
  
  

Ventilation

• Your greenhouse will have to be adequately ventilated. For an inexpensive option, go with a kit that includes a ventilated roof. More expensive kits have ventilated roofs that are temperature sensitive, opening and closing as the temperature changes. As an alternative to ventilated roofs, purchase a kit which contains exhaust fans controlled via thermostat.