greenhouse design

時(shí)間(jiān)：2024-05-18 18:07:29

Greenhouse structures and all parts thereof shall be designed and constructed to safely support all 

loads specified in this manual and the building code. These loads include the dead and live, 

collateral loads, environmental loads and equipment loads specified by the purchaser. 

The design of greenhouse structures, the load effect on the individual components and 

connections shall be by rational engineering analysis methods. Rational engineering analysis is a 

computational analysis, either by hand or computer, that uses accepted load distribution and 

determination methods. Unusual structural and construction methods shall be based on 

engineering analysis or physical testing by an approved laboratory.

Greenhouse structures shall be analyzed for all building code required load conditions. Elements 

and components shall be designed for load combinations specified in the building code or 

referenced standards. 

Design Requirements

Prior to design the manufacturer should obtain local load information, i.e. wind, snow, etc. 

Information should include:

Code of jurisdiction

Determination of loads:

• Roof Live Load

• Wind speed (3-second gust wind speeds)

• Snow load (ground snow load)

• Earthquake zone or design spectra

Soil type and allowable pressure

Required Information on Plans

Certain information must be shown on the construction drawings. The following information 

shown below is required even if it is not a controlling design load. Information to be provided on 

the plans includes:

• Dead Loads

• Roof Live Loads

• Collateral Loads (irrigation equipment, including water)

• Plant loads

• Snow Loads

Ground Snow Load pg

Flat-roof snow load, pf 

Snow exposure factor, Ce

Snow load importance factor, Is

Thermal factor, Ct

• Wind Load

Basic wind speed (3 second gust), miles per hour

Wind importance factor, Iw and building category

Wind exposure category

Applicable internal pressure coefficient and prevailing wind direction

Design Wind Pressure on Components and cladding. 

Exterior components and cladding materials are not specifically designed by the 

Design Professional.

• Earthquake design data

Seismic use group

Spectral response coefficients (SDS and SD1)

Site class

Basis seismic-force resisting system

Design base shear

Analysis procedure

• Flood load - If a building is located in a flood hazard area, established by a 

jurisdiction having authority, the following shall be shown for areas not subject to 

high-velocity wave action

Elevation of the lowest floor

Elevation to which any nonresidential building will be dry floodproofed

• Foundation Design 

Reactions of structural elements when the foundation or other systems are to be 

designed by others. If the structure is designed for future additions, the 

foundation information should include the probable design load information.

Additions and alterations

Additions to existing greenhouses may be made. The new structure shall not make the existing 

structure unsafe. The definition of unsafe and dangerous is included in the code or supporting 

documents. For structural purposes it is related to the percent of overstress in structural members.

When a greenhouse is added to an existing building, the capability of the building to withstand 

any loads superimposed by the greenhouse shall be verified including lateral loads due to 

attachment and snow drift loads due to proximity. 

Alterations may be made to any greenhouse if the new work complies with current code 

provisions and any loads imposed on the existing structure do not create an unsafe condition. 

Allowable stress design vs. strength design requirements - Design of typical greenhouse 

structures may be made by using the allowable stress design (ASD) or the strength (LRFD) 

design methods. The load combination equations used will depend on the design method. The 

ASD is the most common approach used by most engineers for greenhouse structures. 

 Safety factors for greenhouse components - Safety factors for the structural members are 

included in the code referenced standards. 

Greenhouse classification (Code occupancy group under IBC 2000) - Greenhouse 

structures may be considered an occupancy classification “U” when used as a Production 

Greenhouse. Research facilities may be considered the same .Commercial greenhouse structures used for retail use are considered as a “B” or “M” occupancy 

classification. This is based on the fact that the building is normally occupied. 

Deflection and Drift - Deflection of greenhouse components are defined in IBC - Table 

1604.3. There is no criteria limiting drift. The engineer should consider the serviceability 

requirements of the building,