Framing of Your Greenhouse Doors and Vents
Building your DIY greenhouse from scratch allows you to do things your way. You can choose the material, type and size of the greenhouse, the kind of glazing you want to use and the number of doors and windows to install. But there are some basic considerations you have to keep in mind when framing your greenhouse in order to make it to function as a perfect environment for growing plants. One very important consideration for plant growth and proper greenhouse management is air circulation.
Framing Doors for a Greenhouse
Whether you are building a poly tunnel, a Quonset type greenhouse with PVC hoops, wooden A-frame structure or a frame with the
gabled roof, you have to provide space for installing a door. A door will not only provide you with easy access to the interior, but if designed to do so can aid in ensuring adequate air circulation.
One way to use the door to increase the circulation of air is to make your door in two parts (a Dutch door), so that you can keep the top part open. Hot air rises up, and by leaving the bottom part of the door closed, you prevent the cold from seeping in, but allow the warmer air to escape via the opened top section.
Framing a door for any type of the greenhouse is very similar. Most DIY greenhouse builders use 2”x4” pressure treated pine lumber or cedar to frame the two vertical walls (front and back) and leave an opening for a door. Having two doors, both in the front and back walls will aid in creating good circulation.
Doors of greenhouses are normally glazed with the same material as the walls and the roof – polyethylene, glass or polycarbonate panels. If using heaving glazing like glass, you will need to make sure your doorframe and hinges can support the weight required of them.
Vents on a Greenhouse
Vents or windows on any type of greenhouse serve the purpose to increase airflow and circulation and to provide some cooling during the hottest months. Before framing your greenhouse, you should carefully consider where to put vents. In poly tunnel greenhouses, the only choice is either front or back wall, or both, because they are framed with wood. Adding a frame for a simple window above the door, or next to it is fairly easy.
If you frame your greenhouse to accommodate panels with glazing, it is simple to make one or a few panels on hinges, so that you can open them when needed.
Louvered windows also provide a simple and easy way to provide some fresh air when needed. They can be installed on the front and back wall of A-frame or Quonset type greenhouse, or anywhere on vertical walls in a gable type greenhouse frame.
The position of greenhouse vents is very important because your goal is to create as much air circulation as possible. Placing two vents on two opposite sides of a greenhouse ensures cross-circulation. Roof vents are also good, as the hot air rises and the temperature in the greenhouse can be lowered in the summer simply by opening a vent.
Vents can be manual or automatic. There are venting systems on the market that are powered by solar cells. They open and close
automatically as the temperature changes
To increase air circulation further, you can place fans in front of vents. This is a simple and cheap change that you can make that will lead to great results if you are having an issue with your greenhouse being to warm for proper plant growth.
By carefully planning the position of your doors and vents while framing your greenhouse, you will ensure excellent air circulation in your DIY greenhouse. Temperature, as we is aware is one of the most important conditions for creating a healthy and optimal environment for your plants, proper circulation is an important part of the equation.