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9 Cards in this Set
- Front
- Back
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What are the two types of standard peak greenhouses? |
Post and truss Rigid frame |
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What are the advantages of a standard peak post and truss greenhouse? |
- clear span up to 60' wide (approx 20m) -can be covered with rigid plastic or glass -suitable for a ridge and furrow range |
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What are the disadvantages of a standard peak post and truss greenhouse? |
- excessive shading if the truss system is used - steel or aluminum reduce shading but increase cost - strong lateral wind loads require suitable foundation/posts to resist wind load. |
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What are the Advantages of a standard peak with a rigid frame greenhouse? |
- high strength per unit of material used - clear span up to 40' feet - suited to single or double poly - suited to ridge and furrow (gutter connected) design |
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What are the disadvantages of the standard peak rigid frame greenhouse? |
Expensive foundation required to resist wind load |
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Gothic arch advantages? |
-simple inexpensive construction - pleasing aesthetics - clear span -plastic or rigid plastic may be used - good height near side wall |
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Disadvantages of Gothic arch? |
-height increases wind load - greater exposed wall = more heat loss - not suited to ridge and furrow design -an increase in width causes an increase in height |
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Advantages of a Quonset? |
-simple efficient and in expensive construction -clear span up to 40' (13m) -minimum shading from steel structure - one piece plastic cover single or double inflated layers -comes in kits -ideal for low crops |
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Disadvantages of Quonset? |
-not suited to ridge and furrow design -snow build up is possible -curved sidewall restricts height near the sidewalk therefore these greenhouses are not suitable for taller crops to grow on the sides of the greenhouse |
