Construction:
For walls, roofs, floors, windows, and doors, constructions are “built” from the included materials. Each layer of the construction is a material name listed in order from “outside” to “inside”. Up to ten layers (eight for windows) may be specified. “Outside” is the layer furthest away from the Zone air (not necessarily the outside environment). “Inside” is the layer next to the Zone air.
Information from the EnergyPlus Input Output Reference:
Field: Name
This field is a user specified name that will be used as a reference by other input syntax. For example, a heat transfer surface (ref: Surface:HeatTransfer) requires a construction name to define what the make-up of the wall is. This name must be identical to one of the CONSTRUCTION definitions in the input data file.
Field: Outside Layer
Each construction must have at least one layer. This field defines the material name associated with the layer on the outside of the construction—outside referring to the side that is not exposed to the zone but rather the opposite side environment, whether this is the outdoor environment or another zone. Material layers are defined based on their thermalproperties elsewhere in the input file. As noted above, the outside layer should NOT be a film coefficient since EnergyPlus will calculate outside convection and radiation heat transfer more precisely.
Field(s) 2-10: Layers
The next fields are optional and the number of them showing up in a particular CONSTRUCTION definition depends solely on the number of material layers present in that construction. The data expected is identical to the outside layer field (see previous field description). The order of the remaining layers is important and should be listed in order of occurrence from the one just inside the outside layer until the inside layer is reached. As noted above, the inside layer should NOT be a film coefficient since EnergyPlus will calculate inside convection and radiation heat transfer more precisely.