The allowable deflection of any structural member under the live load listed in Sections R301.5 and R301.6 or wind loads determined by Section R301.2.1 shall not exceed the values in Table R301.7.
TABLE R301.7 ALLOWABLE DEFLECTION OF STRUCTURAL MEMBERSb, c
Note: L = span length, H = span height.
TABLE R301.7 ALLOWABLE DEFLECTION OF STRUCTURAL MEMBERSb, c
| STRUCTURAL MEMBER | ALLOWABLE DEFLECTION |
| Rafters having slopes greater than 3:12 with finished ceiling not attached to rafters |
L/180 |
| Interior walls and partitions | H/180 |
| Floors | L/360 |
| Ceilings with brittle finishes (including plaster and stucco) |
L/360 |
| Ceilings with flexible finishes (including gypsum board) |
L/240 |
| All other structural members | L/240 |
| Exterior walls‒wind loadsa with plaster or stucco finish |
H/360 |
| Exterior walls‒wind loadsa with other brittle finishes |
H/240 |
| Exterior walls‒wind loadsa with flexible finishes | H/120d |
| Lintels supporting masonry veneer wallse | L/600 |
Note: L = span length, H = span height.
- For the purpose of the determining deflection limits herein, the wind load shall be permitted to be taken as 0.7 times the component and cladding (ASD) loads obtained from Table R301.2(2).
- For cantilever members, L shall be taken as twice the length of the cantilever.
- For aluminum structural members or panels used in roofs or walls of sunroom additions or patio covers, not supporting edge of glass or sandwich panels, the total load deflection shall not exceed L/60. For continuous aluminum structural members supporting edge of glass, the total load deflection shall not exceed L/175 for each glass lite or L/60 for the entire length of the member, whichever is more stringent. For sandwich panels used in roofs or walls of sunroom additions or patio covers, the total load deflection shall not exceed L/120.
- Deflection for exterior walls with interior gypsum board finish shall be limited to an allowable deflection of H/180.
- Refer to Section R703.8.2.