sloped bond beam

[broncosfan]

We called out a continuous reinforced masonry bond beam near a roof. The roof elevation slopes. The bond beam is acting as a chord. Is it common for the bond beam to slope with the roof? Is this easy for contractors? How is this done since blocking is in 8" increments? Would it just be better to place the top of the bond beam near the low point of the roof and just keep it at one elevation? There is an approximate change in roof elevation along the wall of 2'-0". Thanks.

 

[UcfSE]

The masonry will be "racked back", meaning it will be stair stepped roughly following the roof slope. You will then have a cast-in-place bond beam that slopes with the roof. I would leave the lintel screen down one course of block so that the top course of block will get poured along with the raked concrete beam and tie them together along with whatever reinforcing you come up with. The location of the stair steps for the masonry will be determined by how deep you designate that concrete sloped beam, a.k.a. a "raked" bond beam or tie beam, and the slope of the roof that the top of the concrete tie beam has to follow.

 

[broncosfan]

What's a lintel screen? So the bond beam will be 8" deep at the low point and 24" deep at the high point. The bottom of the bond beam will remain at the same elevation, while the top of the bond beam will step to follow the roof slope. Will the rebar (2#7 in a 12" thick wall) slope also? Will shells of block need to be busted out to let the rebar slope? Thanks.

 

[lkjh345]

BroncosFan:

I use stepped bond beams. The bond beam starts at the lowest point in the wall, and runs until there is a full course of masonry above it, then steps up to the next course. I generally show to overlap the lengths of the two beams 2 to 4 feet (depending on bar sizes used in the bond beams) so the bond beam is 'spliced'.

 

[UcfSE]

Lintel screen is what is used in my area to prevent the entire cmu wall from pouring instead of only the bond beam. It is a roll of screen slightly less wide than the wall that goes under the first course to pour.

The bond beam is as deep as you want it. The top of the concrete slopes with the roof. The bottom will step with the cmu. The rebar may be laid on top of the masonry or put up on chairs and usually slopes with the roof to be parallel with the top of the bond beam.