2009 IBC section 2308.12.8 Sill plate anchorage

[joetheinspector]

are 3 inch by 3 inch sill plate washers required on all sill plate bolts? or just on exterior means of egress components? if just exterior means of egress components (what does that mean)?

2308.12.7 Anchorage of exterior means of egress components

IBC section 2308.12.8 Sill plate anchorage . . . washers shall be a minimum of 0.229inch by 3 inches by 3 inches. . .

We are in a seismic design category D. In the previous code the 3x3 washers were required on all sill botls. Is there another place in the 2009 IBC that addresses 3 inch by 3 inch sill plate washers? seismic zone D

Thanks for any help with this

 

[Mark K]

Do not have a copy of the 2009 IBC handy but the use of the large washers was intended to improve resistance to wind and earthquake forces not address means of egress concerns.

 

[mtlogcabin]

2009 IBC

2308.12.7 Anchorage of exterior means of egress components.

Exterior egress balconies, exterior exit stairways and similar means of egress components shall be positively anchored to the primary structure at not over 8 feet (2438 mm) o.c. or shall be designed for lateral forces. Such attachment shall not be accomplished by use of toenails or nails subject to withdrawal.

No 3"x 3" washers are only required on the anchor bolts at the sill plate based on an anchor bolt spacing of 4 ft O C.

 

[my250r11]

2308.2.2 Buildings in Seismic Design Category B, C, D or E. Buildings of conventional light-frame construction in Seismic Design Category B or C, as determined in Section 1613, shall comply with the additional requirements in Section 2308.11.

Buildings of conventional light-frame construction in Seismic Design Category D or E, as determined in Section 1613, shall comply with the additional requirements in Section 2308.12.

2308.12.8 Sill plate anchorage. Sill plates shall be anchored with anchor bolts with steel plate washers between the foundation sill plate and the nut, or approved anchor straps load rated in accordance with Section 1716.1. Such washers shall be a minimum of 0.229 inch by 3 inches by 3 inches (5.82 mm by 76 mm by 76 mm) in size. The hole in the plate washer is permitted to be diagonally slotted with a width of up to 3/16 inch (4.76 mm) larger than the bolt diameter and a slot length not to exceed 13/4 inches (44 mm), provided a standard cut washer is placed between the plate washer and the nut.

So in my option They are additional requirements as are a long list of other thing in 2308.12.

 

[my250r11]

Also I would check the approved plans to see what was called out and approved.

 

[mtlogcabin]

Please look at 2308.2 Limitations

You may not even be able to use 2308 if one of the limitations apply.