DOE-2 Reference Manual Version 2.1 - DOE2.com

11. LAYERSThe LAYERS instruction is used to specify the sequence of material layersof a construction; that is, it describes the cross section of a wall, roof,etc. It is used when no LAYERS code-word in the DOE-2 LAYERS Library isappropriate for a given exterior wall, exterior floor, roof, interior floor,interior wall, underground wall, or underground floor. The information in aLAYERS instruction for an interior floor, interior wall, underground wall, orunderground floor will be used only for the calculation of Custom WeightingFactors; for heat flow, these surfaces are treated like "quick" surfaces.U-nameLAYERSINSIDE-FILM-RESMATERIALis required for this instruction. It identifies this LAYERSin a subsequent CONSTRUCTION instruction.This command tells LOADS that the data to follow identifythe layers of material that are in a construction, the orderof the layers, and the layer thicknesses. It tells the LDLProcessor to calculate the response factors for the wall.specifies the combined convective and radiative air filmresistance for the inside wall surface. Note that the defaultof .68 is an appropriate value for vertical walls.For horizontal surfaces, such as ceilings and floors, thesuggested inside-film-resistance can be found in thefollowing table. Because only one value is allowed for eachsurface, the user should decide which is more important,cooling or heating.CoolingHeatingCeilings (Heat Flowing Downward) (Heat Flowing Upward).61 .92Floors (Heat Flowing Upward) (Heat Flowing Downward).92 .61If the user cannot decide which is more important, coolingor heating, he can accept the default value of .68. Forexterior walls and roofs, the outside-film-resistance iscalculated by the program. For interior walls, the air filmdescribed in INSIDE-FILM-RES is the film on the side of thewall that is in the SPACE where the wall is specified. Forthe calculation of the U-value for an INTERIOR-WALL, theINSIDE-FILM-RES is duplicated on the other surface (oppositeside). Do not input it as a MATERIAL.identifies a list of MATERIAL instruction U-names or a listof DOE-2-prespecified material code-words (see Cha~ X) or alist of ASHRAE-prespecified material code-words from Table 8on p. 25.10 of the 1977 ASH RAE Handbook of Fundamentals(Ref. 5). Do not include the code-words AO or EO from Ref.5. When using the last approach, enter the code-word HF-x,where x is the "Code Number" of the material listed in Table8 on p. 25.10 of Ref. 5 (Table 8 is reprinted earlier inth i s chapter).II 1.76 (Revised 5/81)