The basic parameters that define a pre-engineered building are: Building width, Building length, Building height, Roof slope, End bay length, Interior bay length and Design loads.
Width:-No matter what primary framing system is used, the building width is defined as the distance from outside of eave strut of one sidewall to outside of eave strut of the opposite sidewall. Building width does not include the width of Lean-To buildings or roof extensions.
Length:-The longitudinal length of the building measured from out to out of end wall steel lines.
Height:-Building height is the eave height which usually is the distance from the bottom of the main frame column base plate to the top outer point of the eave strut. When columns are recessed or elevated from finished floor, eave height is the distance from finished floor level to top of eave strut.
Roof Slope(x/10):-This is the angle of the roof with respect to the horizontal. The most common roof slopes are 0.5/10 and 1/10. Any practical roof slope is possible.
End Bay Length:-The distance from outside of the outer flange of endwall columns to center line of the first interior frame column.