This is part of a paper I wrote for an International Code Council Retrofit Code Committee.
Exclusive Upper Top Plate Nailing Is Found in:
LADBS Plan Set 1
Special Design Provisions For Wind And Seismic
Simpson StrongTie Plan Set
City of Seattle Guidelines
American Plywood Association Shear Wall Details
Lower And Upper Top Plate Nailing is Found in:
Standard Plan A
In the credits at the beginning of this plan set it admits much of the material contained therein came from Standard Plan A.
Exclusive Lower Top Plate Nailing:
CUREE Publication W-17, Page 19 Figure 1.7
This detail is contrary to 25 years of precedents established by multiple jurisdictions. If the standard is to be accepted, its use must be justified by both engineering theory and empirical evidence. Including this detail is essentially telling jurisdictions that may have followed the 5 guidelines and the SDPWS for years, that they had it wrong the whole time. There will be a lot of resistance to using this detail in particular, and the entire standard in general, unless this and other details peculiar to the standard can be fully justified.
Be Sure and Look at The Images Below.
Upper top plate Nailing: Figure 7, American Plywood Association Introduction to Lateral Design
Upper Top Plate Nailing: American Plywood Association, Figure 4, Building For High Wind Resistance in Light-Frame Wood Construction
Upper Top Plate Nailing: CEBC
Upper Top Plate Nailing: Simpson Plan Set
Upper Top Plate Nailing: Seattle Plan Guidelines
Upper Top Plate Nailing: Portland Guidelines
Upper Top Plate Nailing: LADBS Plan Set
Upper Top Plate Nailing: SDPWS
Upper an Lower Top Plate Nailing: Standard Plan A
Upper and Lower Top Plate Nailing: FEMA DR-4193-RA2
Exclusive Lower Top Plate Nailing: CUREE W-17, Page 93, Fig 1.7