huangyhg

masonry lintels
in a masonry lintel requiring two or more couses, the bottom course will be composed of bond beam units with horizontal rebar. what about the required courses on top of that? should they also be bond beam units, common cored units or either, depending on the application?
thank you ...

for 16" depth, you could you a jamb block (commonly call a horse collar). it is 16" deep by 8" long. check with the architect to see if that appearance is acceptable.
deutero:
be careful with your terminology. you want to use a lintel unit as your bottom course, not a bond beam unit. these are different blocks and will effect the 'd' of your rebar significantly. with a lintel unit, your bottom bars will be approximately 2.5" from the bottom, with a bond beam unit your bottom bars will be about 5.5" from the bottom.
for the top course of a 16" deep unit, i general just use regular open block cmu.
for a 24" deep (or deeper) lintel, i generally will use a bond beam unit with a couple of #4 horizontal bars extended 2'-0" past the opening to tie the top of the lintel together.
in the field you may not find a distinction between bond beam units and lintel units. if there can be any confusion, make sure you detail where the steel needs to go and whether a precast lintel may be used instead of relying on terminology.

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