Our Design - The Harvester Series Hobby Greenhouses 
 

Introduction There are many different greenhouse designs available in today's market. Round, square, rectangular, gable style, dome style, barn style, etc. Each have their own beneficial features. Each have their weaknesses. At North American Greenhouses we studied most all of these designs and evaluated their structure, materials, features and combined all of the positive features we found into one design that is functional, strong as well as economical. Our line of hobby greenhouses are available in both a gable style and our 8' x 12' model (Harvester IV is available in a barn style. Why a barn style? Higher sidewalls and additional head room due to the dual angle roof line (see picture to the right). This is our Harvester IV Barn Style hobby greenhouse. And, our prices are unbeatable. Dollar for dollar, these are the best value available in the market today!
	Greenhouse Dimensions We selected three (3) sizes to begin with in 2010. A 6' W x 8' L, 8' W x 10' L and 8' W x 12' L. All rectangular in shape.  A small 6' x 8' will fit most any area and is ideal for a patio or deck. The larger 8' x 10' and 8' x 12' allow plenty of space to grow a wide variety of plants, vegetables and flowers.  By adding multiple levels of shelving and even hanging baskets you will have a lot of space for your favorite plants! Our 2011 models will include an optional extension kit that will allow you to length the greenhouses in 4' increments. A 6' x 8' unit plus a 4' extension kit will make a 6' x 12' greenhouse. Additional extension kits can made the greenhouse as long as you wish! Each extension kit will have two roof vents with auto openers. It also includes the extension for the base.
Aluminum Frame The Harvester frames are made of extruded aluminum. Although some greenhouses are made from polycarbonate, the added strength of aluminum was our choice. We acknowledge that a polycarbonate frame does not conduct heat and cold like aluminum does, we felt that the strength of aluminum was vitally important. As seen in the picture to the right, the corners are re-enforced with diagonal plates and aluminum sway bars are added throughout the structure to further strengthen the greenhouse. People often ask how strong a wind will our greenhouses sustain. Short of a tornado or hurricane, Harvester greenhouses are not effected by strong winds. They can be affected if not properly anchored to the ground. If not anchored, the entire structure could be lifted and moved, but the individual panels and frame are very strong.
	Galvanized Steel Base Harvester Greenhouses have a galvanized steel base that is powder coated green. This is included at no additional cost. Many hobby greenhouses have a galvanized steel or aluminum base and most charge extra for the base. The base is important as it provides a strong surface to attach the walls to. It also insures that the greenhouse is perfectly square. The vertical members shown in the picture to the right are pounded into the ground as anchor stakes. They are securely fastened to the horizontal frame and will prevent the greenhouse from moving laterally.  If the greenhouse is placed in a strong wind area, additional anchors can be added to prevent vertical movement of the structure. Although shown in aluminum color, our bases are dark green powder coated galvanized steel.
Polycarbonate Panels A vast majority of hobby greenhouses use a single layer polycarbonate or a thin 4mm thick twin walled polycarbonate panel. The single layer polycarbonate is used in the SnapNGrow greenhouses and several other brands. It is a clear material which is strong in the sense that when impacted is absorbs the shock and "bounces" back. Superior to that is the 4mm twin walled polycarbonate panel. The double layer creates a small amount of insulative value, but fairly inconsequential compared to a thicker polycarbonate material. We selected a 10mm twin wall polycarbonate panel with UV protection. Almost 1/2" thick it not only provides insulative value (1.89 R Value) but also adds significant lateral strength to the structure. There are thicker and stronger twin wall and triple wall polycarbonate panels available, but they are substantially more expensive. We believe the 10mm is both strong and economical. The 10mm panels offer 32% more insulative value than standard 4mm panels.
	Sliding Doors Our 8' x 10' and 8' x 12' models have double sliding doors, wide enough for a wheel barrow and large boxes. Our smaller 6' x 8' has a single wide sliding door. Why sliding? We've learned that hinged doors are not as strong and excessive stress on the hinges can make the doors not close completely.  The hinged doors also do not require space in front of the green to open. They simply slide to each side and remain in that position until closed. Hinged doors, when opened, will tend to partially close until propped open or latched open to the main greenhouse structure. On our 6' wide models, the sliding door is 3' wide. On the 8' wide models it is 4' wide when both halves are slid open.
Roof Vents with Auto Openers Adequate ventilation is vital to the well being of your plants. More plants die for too much heat than from being cold! All of our greenhouses include roof vents with auto-openers. On the 6' x 8' there are two roof vents. On the 8' x 12' and 8' x 14' greenhouses, there are 4 roof vents. Many similar greenhouses have roof vents but they do not include auto openers. Auto openers automatically open and close your roof vents when the temperature gets too hot or too cold. If you're away for the weekend or even a day, your plants could be severely damaged if adequate ventilation is not available. In the evening as it gets cooler, the auto openers sense this and close the roof vents to retain as much heat as possible that was gained during the day.
	Sway Bars Diagonal sway bars make the our greenhouses extra strong. They prevent lateral "swaying" which could occur if the structure only had vertical and horizontal frame members. These sway bars are attached to the base on one end and the vertical frame members on the other end. There are 8 such sway bars, one pair at each corner. Anchor Staves These vertical members of the base frame pound into the ground to anchor the entire structure to the ground.  These stakes can either be simply placed in the ground or inset into concrete footers (recommended)
	These base legs are designed to be inserted into the ground. First, dig for post holes about 18" deep. Next set your greenhouse base on the ground with the vertical staves placed in the holes. Make sure the base in level and square. Finally, fill the holes with concrete. Let dry 24 hours and then assembly your greenhouse on top of the base.
Summary If you have questions about our design, please contact us at most anytime. We believe that our Harvester Series greenhouses are ideal for the hobby greenhouse grower. We also know that our prices are the best in the industry. Shop and compare and you will come to the same conclusions.