Product(s):	Hevacomp Mechanical Designer
	Version(s):	V8i
	Environment:	N/A
	Area:	Netsys Ductwork
	Subarea:	N/A

Overview

Roughness values used in Netsys Duct sizing calculations are dependant on the type of ductwork being used. 

Method

The following table displays the roughness value for each ductwork type:

Ductwork type	Roughness
Circular galvanised sheet	0.15
Circular spirally wound	0.075
Rectangular galvanised sheet	0.15
Flat oval	0.075
Flexible	3