Standard Deflections
Listed below are the standard deflection limitations used to design each building member according to code requirements.
IBC 2000 / 2003
Component |
Live Load Alone |
Wind1 or Snow Load Alone |
Dead Load + Collateral Load + Live Load or Snow Load |
Purlins and Eave Struts Not Supporting a Ceiling Supporting a Plaster Ceiling Supporting a Non-Plaster Ceiling |
L/150 L/360 L/240 |
L/150 L/360 L/240 |
L/180 L/180 L/240 |
Girts |
N/A |
L/90 |
N/A |
Endwall Rafters Not Supporting a Ceiling Supporting a Plaster Ceiling Supporting a Non-Plaster Ceiling |
L/150 L/360 L/240 |
L/150 L/360 L/240 |
L/180 L/180 L/240 |
Endwall Columns |
N/A |
L/90 |
N/A |
Main Frame Rafters Not Supporting a Ceiling Supporting a Plaster Ceiling Supporting a Non-Plaster Ceiling |
L/150 L/360 L/240 |
L/150 L/360 L/240 |
L/180 L/180 L/240 |
Main Frame Lateral Drift Metal Walls Masonry Stucco/Dryvit |
N/A N/A N/A |
H/603 Notes 2, 3, 4 H/1003,4 |
N/A N/A N/A |
Notes:
Wind Load taken as 0.7 times the 50-year reoccurrence value for components and cladding.
Per AISC Design Guide 1, a 1/16" crack allowed at the base of the wall taken at a point matching the top of the wall.
Under a 10-year mean occurrence value assumed to be 75% of the 50-year value.
Minimum Value. Project-specific requirements may result in a more stringent criteria.
SBC 1999 / 1997 / 1994
Component |
DL + CL + LL |
DL + WL |
Purlins |
L/180 |
L/180 |
Eaves |
L/180 |
L/180 |
Girts |
L/120 |
L/120 |
Endwall Rafters |
L/180 |
L/180 |
Endwall Columns |
L/120 |
L/120 |
Main Frame Rafters |
L/180 |
L/180 |
UBC 1997 / 1994
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
Eaves |
L/180 |
L/180 |
Girts |
L/120 |
L/120 |
Endwall Rafters |
L/180 |
L/180 |
Endwall Columns |
L/120 |
L/120 |
Main Frame Rafters |
L/180 |
L/180 |
BOCA 1999 - 180 / 1996 - 180 / 1993 - 180*
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
*Note:
The 180 designation refers to the deflection limitations imposed by the code. This Code can be used if there are no attached masonry or suspended ceilings used in construction.
BOCA 1999 - 240 / 1996 - 240 / 1993 - 240**
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/240 |
L/240 |
|
Eaves |
L/240 |
L/240 |
|
Girts |
L/240 |
L/240 |
|
Endwall Rafters |
L/240 |
L/240 |
|
Endwall Columns |
L/240 |
L/240 |
|
Main Frame Rafters |
L/240 |
L/240 |
**The 240 designation refers to the deflection limitations imposed by the code. This Code can be used if their are attached masonry or suspended ceilings used in construction.
ASCE-7 2002 / 1993
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
Florida 2004 / 2001
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
Indiana 1998
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
Kentucky 2002
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
Kentucky BOCA 1999 - 180 / 1996 - 180 / 1993 - 180*
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
*Note:
The 180 designation refers to the deflection limitations imposed by the code. This Code can be used if there are no attached masonry or suspended ceilings used in construction.
Kentucky BOCA 1999 - 240 / 1996 - 240 / 1993 - 240**
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/240 |
L/240 |
|
Eaves |
L/240 |
L/240 |
|
Girts |
L/240 |
L/240 |
|
Endwall Rafters |
L/240 |
L/240 |
|
Endwall Columns |
L/240 |
L/240 |
|
Main Frame Rafters |
L/240 |
L/240 |
**The 240 designation refers to the deflection limitations imposed by the code. This Code can be used if their are attached masonry or suspended ceilings used in construction.
California 1997
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
Minnesota 2003 / 1998
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
New Jersey 2000
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
Ohio Building Code 2005 / 2002
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
OBBC 1998 - 180*
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
*Note:
The 180 designation refers to the deflection limitations imposed by the code. This Code can be used if there are no attached masonry or suspended ceilings used in construction.
OBBC 240 - 240**
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/240 |
L/240 |
|
Eaves |
L/240 |
L/240 |
|
Girts |
L/240 |
L/240 |
|
Endwall Rafters |
L/240 |
L/240 |
|
Endwall Columns |
L/240 |
L/240 |
|
Main Frame Rafters |
L/240 |
L/240 |
**The 240 designation refers to the deflection limitations imposed by the code. This Code can be used if their are attached masonry or suspended ceilings used in construction.
Michigan 2003
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
Wisconsin 2002 / 1997
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
MBMA 1996
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
New York 2002 / 1993
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |
North Carolina 2002 / 1998 / 1996
|
Component |
DL + CL + LL |
DL + WL |
|
Purlins |
L/180 |
L/180 |
|
Eaves |
L/180 |
L/180 |
|
Girts |
L/120 |
L/120 |
|
Endwall Rafters |
L/180 |
L/180 |
|
Endwall Columns |
L/120 |
L/120 |
|
Main Frame Rafters |
L/180 |
L/180 |