nyc building code 2003 design of masonry wall clarification

huangyhg

nyc building code 2003 design of masonry wall clarification
hi,  
section 6.4.1 multi story buildings (page 129 volume ii,rs-10 nyc building code 2003)  is not clear to me.
regarding  item a) exterior solid  walls-..."the thickness of solid exterior masonry bearing walls shall be at least 8 in. for the top floor and 12 in. for a maximum of 55 feet measured downward from the top floor level. any addtional height should be provided by 16 in lower walls up to a maximum height of 104 ft. building taller  than 104 ft. shall be structurally analyzed and designed. the slenderness  ratio shall not exceed 20. "  
question:  where in elevation is the 16 inch wide  wall required ? at 55 feet ?  please advise someone.
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i don't have that book but it sounds like it should be like this:
top floor: 8 inch (whatever height top floor is, say 10ft from floor to roof)
walls below top floor: 12 inches, which can be used up to a maximum of 55 feet
therefore the 16 inch would start at (10 feet+55 feet)=65 feet from the top of the highest floor.
i don't really like the phrase: "buildings taller than 104 ft. shall be structurally analyzed and designed". to some people it may sound like "so up to 104' just put whatever reinforcing you choose."
(16 inch starts at 65 feet from roof.)